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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ExternalGeneralAndAdministrativeCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">External general and administrative costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenuesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenuesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenues [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestPaidNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash paid for interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestPaidNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Paid, Excluding Capitalized Interest, Operating Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AccruedResearchAndDevelopmentCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued research and development current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AccruedResearchAndDevelopmentCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Research And Development Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AccruedResearchAndDevelopmentCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued research and development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentCovenantDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Covenant Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentCovenantDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument, covenant description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number of Operating Segments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of operating segment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning balance, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending balance, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Hierarchy and NAV</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Hierarchy and NAV [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel2Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Level 2 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel2Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 2 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_EmpaveliAndAspaveliMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Empaveli And Aspaveli [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_EmpaveliAndAspaveliMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">EMPAVELI and Aspaveli member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_EmpaveliAndAspaveliMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EMPAVELI and Aspaveli [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongtermDebtTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term Debt, Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongtermDebtTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingOtherItemAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other segment items</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingOtherItemAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, Other Segment Item, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CustomerDMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer D [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CustomerDMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer D [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CustomerDMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Customer D.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AggregateMilestonePaymentsUponAchievementOfSpecifiedOneTimeRegulatoryDevelopmentAndCommercialMilestoneEvents_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Aggregate milestone payments upon achievement of specified one time regulatory development and commercial milestone events.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AggregateMilestonePaymentsUponAchievementOfSpecifiedOneTimeRegulatoryDevelopmentAndCommercialMilestoneEvents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Aggregate Milestone Payments Upon Achievement of Specified One Time Regulatory Development and Commercial Milestone Events</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AggregateMilestonePaymentsUponAchievementOfSpecifiedOneTimeRegulatoryDevelopmentAndCommercialMilestoneEvents_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate milestone payments upon achievement of specified one time regulatory development and commercial milestone events</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AvailableAdditionalDrawAmountUponSatisfactionOfCashRequirements_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Available Additional Draw Amount Upon Satisfaction of Cash Requirements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AvailableAdditionalDrawAmountUponSatisfactionOfCashRequirements_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Available additional draw amount upon satisfaction of cash requirements.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AvailableAdditionalDrawAmountUponSatisfactionOfCashRequirements_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Available additional draw amount upon satisfaction of cash requirements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and Contingencies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_Inventory_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total inventory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_Inventory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_Inventory_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Inventory.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductOrServiceAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product and Service</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductOrServiceAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product and Service [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lender Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ConvertibleSeniorNotesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Convertible notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ConvertibleSeniorNotesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Senior Notes Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ConvertibleSeniorNotesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Convertible senior notes.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BaseRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Base Rate [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaborative Arrangement and Arrangement Other than Collaborative</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_TimothySullivanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tim Sullivan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_TimothySullivanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Timothy Sullivan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_TimothySullivanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Timothy Sullivan.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares expected to be purchased under employee stock purchase plan</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ExternalResearchAndDevelopmentCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">External research and development costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ExternalResearchAndDevelopmentCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">External Research and Development Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ExternalResearchAndDevelopmentCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">External research and development costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskByBenchmarkAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Benchmark [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseNonoperating_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Expense, Nonoperating</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseNonoperating_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseNonoperating_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Interest expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenuesAccountsReceivableAndReservesForProductSalesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product Revenues Accounts Receivable And Reserves For Product Sales [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenuesAccountsReceivableAndReservesForProductSalesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product Revenues Accounts Receivable And Reserves For Product Sales [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenuesAccountsReceivableAndReservesForProductSalesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Product revenues, accounts receivable, and reserves for product sales.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentCarryingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total future minimum payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentCarryingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Principal</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentCarryingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CreditFacilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Credit Facility [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CreditFacilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Credit facility.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementNumberOfResearchPrograms_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaborative arrangement, number of research programs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementNumberOfResearchPrograms_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement Number Of Research Programs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementNumberOfResearchPrograms_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of research programs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SalesMilestonePaymentsBasedOnAchievementOfAnnualSalesMilestones_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestone payments based on annual sales milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SalesMilestonePaymentsBasedOnAchievementOfAnnualSalesMilestones_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sales Milestone Payments Based On Achievement Of Annual Sales Milestones</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SalesMilestonePaymentsBasedOnAchievementOfAnnualSalesMilestones_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sales milestone payments based on achievement of annual sales milestones.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCentralIndexKey_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Central Index Key</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCentralIndexKey_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Central Index Key</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenueAllowancesAndReservesCreditAndPaymentsMade_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Credits and payments made</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenueAllowancesAndReservesCreditAndPaymentsMade_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product Revenue Allowances And Reserves, Credit And Payments Made</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenueAllowancesAndReservesCreditAndPaymentsMade_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Product revenue allowances and reserves, credit and payments made.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Changes in operating assets and liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Operating Capital [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RefundFiledUnderCaresActRelatingToEmployeeRetentionCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Refund filed under CARES Act relating to employee retention credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RefundFiledUnderCaresActRelatingToEmployeeRetentionCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Refund Filed under CARES Act Relating to Employee Retention Credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RefundFiledUnderCaresActRelatingToEmployeeRetentionCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Refund filed under CARES Act relating to employee retention credit.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Common Stock, Shares, Issued, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net proceeds from the sale of the notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromConvertibleDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Convertible Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DavidWatsonMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">David Watson [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DavidWatsonMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">David Watson.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Statement [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MaximumCreditPerEmployeeForEachCalendarQuarter_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum credit per employee for each calendar quarter</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MaximumCreditPerEmployeeForEachCalendarQuarter_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maximum Credit per Employee for Each Calendar Quarter</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MaximumCreditPerEmployeeForEachCalendarQuarter_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Maximum credit per employee for each calendar quarter.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentIncomeNonoperating_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Investment Income, Nonoperating, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentIncomeNonoperating_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentIncomeNonoperating_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment Income, Nonoperating</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentIncomeNonoperating_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Interest income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressStateOrProvince_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, State or Province</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressStateOrProvince_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, State or Province</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net loss before taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net loss before taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Threshold percentage of stock price trigger</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AmortizationOfDiscountsForConvertibleNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amortization of discounts for convertible notes.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AmortizationOfDiscountsForConvertibleNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization Of Discounts For Convertible Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AmortizationOfDiscountsForConvertibleNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization of discounts for convertible notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_InternalSellingGeneralAndAdministrativeCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Internal Selling, General and Administrative Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_InternalSellingGeneralAndAdministrativeCost_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Internal selling, general and administrative cost.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_InternalSellingGeneralAndAdministrativeCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Internal selling, general and administrative costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityRevenueRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Liability, Revenue Recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityRevenueRecognized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MajorCustomersAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SeniorSecuredCreditFacilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Senior Secured Credit Facility [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SeniorSecuredCreditFacilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Senior Secured Credit Facility [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CustomerConcentrationRiskMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer Concentration Risk [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CustomerConcentrationRiskMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer Concentration Risk [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_TwoThousandTwentyConvertibleNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2020 Convertible Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_TwoThousandTwentyConvertibleNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Twenty Convertible Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_TwoThousandTwentyConvertibleNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">2020 Convertible notes.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RoyaltiesEntitledToReceiveAfterFirstCommercialSaleOfApplicableLicensedProductPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalties entitled to receive after first commercial sale of applicable licensed product period.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RoyaltiesEntitledToReceiveAfterFirstCommercialSaleOfApplicableLicensedProductPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalties Entitled To Receive After First Commercial Sale Of Applicable Licensed Product Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RoyaltiesEntitledToReceiveAfterFirstCommercialSaleOfApplicableLicensedProductPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Royalties entitled to receive after first commercial sale of applicable licensed product period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByLiabilityClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liability Class</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByLiabilityClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liability Class [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborationAndLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaboration and License Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborationAndLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaboration And License Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborationAndLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaboration and license agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryRawMaterials_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Raw materials</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryRawMaterials_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Raw Materials, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryRawMaterials_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Inventory, Raw Materials, Gross, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsOfDebtIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payments of transactions cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsOfDebtIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments of Debt Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SFJAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">SFJ Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SFJAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">S F J Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SFJAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">SFJ agreement [member].</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfFinancingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Amortization of debt issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfFinancingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization of Debt Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProceedsFromInitialDrawAmountUnderCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds From Initial Draw Amount Under Credit Facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProceedsFromInitialDrawAmountUnderCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Proceeds from initial draw amount under credit facility.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProceedsFromInitialDrawAmountUnderCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from initial draw amount under credit facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CoverAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cover [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementMaximumExtendableTermOfAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaborative arrangement, maximum extendable term of agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementMaximumExtendableTermOfAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement Maximum Extendable Term Of Agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementMaximumExtendableTermOfAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaboration agreement maximum extendable term</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net loss per common share, basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net loss per common share, basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RegulatoryMilestonePaymentsBasedOnAchievement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Regulatory milestone payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RegulatoryMilestonePaymentsBasedOnAchievement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Regulatory Milestone Payments Based On Achievement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RegulatoryMilestonePaymentsBasedOnAchievement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Regulatory milestone payments based on achievement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AspaveliMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Aspaveli [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AspaveliMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Aspaveli.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AspaveliMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aspaveli [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating expenses:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Expenses [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfOtherReceivables_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Sale of Other Receivables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfOtherReceivables_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable sold</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_TwoThousandNineteenConvertibleNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2019 Convertible Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_TwoThousandNineteenConvertibleNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Nineteen Convertible Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_TwoThousandNineteenConvertibleNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">2019 Convertible notes.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net carrying amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Long-term debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Retained Earnings (Accumulated Deficit), Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Retained Earnings (Accumulated Deficit), Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Retained Earnings (Accumulated Deficit), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated deficit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retained Earnings (Accumulated Deficit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsNonrecurringMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value, Nonrecurring [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsNonrecurringMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Nonrecurring [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current assets:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Prepaid and Other Current Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash used in operating activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided by (Used in) Operating Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RoyaltyExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RoyaltyExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Royalty expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductsAndServicesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product and Service</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductsAndServicesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product and Service [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accumulated Other Comprehensive Income (Loss), Net of Tax, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated other comprehensive loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Other Comprehensive Income (Loss), Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseTermOfContract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease, term of contract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseTermOfContract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Term of Contract</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Property, Plant and Equipment, Net, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Property, Plant and Equipment, Net, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Property, Plant and Equipment, Net, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided by (Used in) Operating Activities [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsRecurringMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value, Recurring [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsRecurringMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Recurring [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenueAllowancesAndReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenueAllowancesAndReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenueAllowancesAndReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product Revenue Allowances and Reserves</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenueAllowancesAndReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Product revenue allowances and reserves.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, par value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Par or Stated Value Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedRoyaltiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued royalties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedRoyaltiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Royalties, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeStockOptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Stock options to purchase common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Unrealized gain on available-for-sale investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrealized gain/(loss) on marketable securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, after Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_KarenLLewisMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Karen L Lewis [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_KarenLLewisMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Karen L Lewis.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SixthStreetFinancingAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sixth Street Financing Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SixthStreetFinancingAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sixth street financing agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfCashFlowsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Cash Flows [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_CounterpartyNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Counterparty Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_CounterpartyNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Counterparty Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Antidilutive Securities, Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities, Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_NurNicholsonMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nur Nicholson [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_NurNicholsonMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Nur Nicholson.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MovementInValuationAllowancesAndReservesRollForward_lbl" xlink:role="http://www.xbrl.org/2003/role/label">SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementEquityComponentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity Components</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementEquityComponentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Components [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PaymentOfConvertibleDebtDiscountsAndCommissions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment of convertible debt discounts and commissions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PaymentOfConvertibleDebtDiscountsAndCommissions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment Of Convertible Debt Discounts And Commissions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PaymentOfConvertibleDebtDiscountsAndCommissions_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment of convertible debt discounts and commissions.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, Address Line One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Address Line One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Basic and Diluted Net Loss per Common Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Shares Outstanding that were Excluded from Calculation of Diluted Net Loss Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Maximum Borrowing Capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum borrowing capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ExchangeAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exchange Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ExchangeAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Exchange Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ExchangeAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Exchange agreements.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_LiabilityComponentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liability Component [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_LiabilityComponentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liability Component [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_LiabilityComponentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Liability component.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Amendment Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amendment Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DebtInstrumentConvertibleThresholdTradingPricePerPrincipalAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Trading price per principal amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DebtInstrumentConvertibleThresholdTradingPricePerPrincipalAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Convertible Threshold Trading Price Per Principal Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DebtInstrumentConvertibleThresholdTradingPricePerPrincipalAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt instrument convertible threshold trading price per principal amount.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument, Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MinimumCashRequirementsToDrawAdditionalLoanUnderCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum Cash Requirements to Draw Additional Loan Under Credit Facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MinimumCashRequirementsToDrawAdditionalLoanUnderCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Minimum cash requirements to draw additional loan under credit facility.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MinimumCashRequirementsToDrawAdditionalLoanUnderCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum cash requirements to draw additional loan under credit facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MarketCapitalizationThresholdPercentageForCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Market Capitalization Threshold Percentage for Credit Facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MarketCapitalizationThresholdPercentageForCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Market capitalization threshold percentage for credit facility.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MarketCapitalizationThresholdPercentageForCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Market capitalization threshold percentage for credit facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MarketCapitalizationThresholdForCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Market Capitalization Threshold for Credit Facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MarketCapitalizationThresholdForCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Market capitalization threshold for credit Facility.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MarketCapitalizationThresholdForCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Market capitalization threshold for credit facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenueAllowanceAndReservesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product Revenue Allowance and Reserves [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenueAllowanceAndReservesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product Revenue Allowance and Reserves [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenueAllowanceAndReservesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Product revenue allowance and reserves.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term inventory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Inventory, Noncurrent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DebtInstrumentConvertibleInitialConversionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Initial conversion price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DebtInstrumentConvertibleInitialConversionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Convertible Initial Conversion Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DebtInstrumentConvertibleInitialConversionPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt Instrument, convertible, initial conversion price.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock upon exercise of stock options, shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VariableRateDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Variable Rate [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_NameOfMajorCustomerDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfDebtTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Outstanding Balance of Convertible Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfDebtTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Debt [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityComponentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity Component</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityComponentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Component [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statistical Measurement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingExpenseInformationUsedByCodmTypeExtensibleEnumeration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, Expense Information Used by CODM, Type [Extensible Enumeration]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermLineOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Line of Credit, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermLineOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term credit facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total interest expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt interest expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Expense, Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Nonoperating Income (Expense), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Nonoperating Income (Expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other (expense)/ income, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reconciliation of cash, cash equivalents and restricted cash to the consolidated balance sheets:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_TwoThousandTenLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2010 License Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_TwoThousandTenLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Ten License Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_TwoThousandTenLicenseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two thousand ten license agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromLinesOfCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Lines of Credit</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfitLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net Income (Loss), Including Portion Attributable to Noncontrolling Interest, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfitLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProfitLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Income (Loss), Including Portion Attributable to Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Preferred Stock, Shares Issued, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Shares Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from exercise of stock options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Stock Options Exercised</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ConvertibleNotesHeldInTreasury_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Notes Held in Treasury</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ConvertibleNotesHeldInTreasury_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Convertible notes held in treasury.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PatentLicenseAgreementWithPennNon-OphthalmicFieldsOfUseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Patent License Agreement with Penn (Non-ophthalmic Fields of Use) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PatentLicenseAgreementWithPennNon-OphthalmicFieldsOfUseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Patent License Agreement With Penn (Non-ophthalmic Fields of Use) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PatentLicenseAgreementWithPennNon-OphthalmicFieldsOfUseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Patent License Agreement with Penn (Non-ophthalmic Fields of Use).</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PayablesAndAccrualsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payables and Accruals [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Cash, Current</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TypeOfArrangementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Axis]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income (Loss), Net of Tax, Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_TwoThousandNineteenConvertibleNotesAndTwoThousandTwentyConvertibleNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2019 Convertible Notes And 2020 Convertible Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_TwoThousandNineteenConvertibleNotesAndTwoThousandTwentyConvertibleNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Two Thousand Nineteen Convertible Notes And Two Thousand Twenty Convertible Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_TwoThousandNineteenConvertibleNotesAndTwoThousandTwentyConvertibleNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two thousand nineteen convertible notes and two thousand twenty convertible notes member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Common Stock, Shares, Outstanding, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Common Stock, Shares, Outstanding, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenueReservesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Product revenue reserves current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenueReservesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product revenue reserves current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenueReservesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product revenue reserves</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Purchase of available-for-sale securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Debt Securities, Available-for-Sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, par value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Par or Stated Value Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from maturity of available-for-sale securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-Sale</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Antidilutive Securities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenueAllowancesAndReservesProvisionRelatedToSalesInTheCurrentYear_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Provision related to sales in the current year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenueAllowancesAndReservesProvisionRelatedToSalesInTheCurrentYear_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product Revenue Allowances And Reserves, Provision Related To Sales In The Current Year</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenueAllowancesAndReservesProvisionRelatedToSalesInTheCurrentYear_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Product revenue allowances and reserves, provision related to sales in the current year.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityInteractiveDataCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Interactive Data Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityInteractiveDataCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Interactive Data Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PaymentForBuyoutOfDevelopmentLiabilityWhichIsDueInTwentyTwentyFive_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment for Buyout of Development Liability which is Due in Twenty Twenty-five</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PaymentForBuyoutOfDevelopmentLiabilityWhichIsDueInTwentyTwentyFive_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment for Buyout of Development Liability which is Due in Twenty Twenty-five</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PaymentForBuyoutOfDevelopmentLiabilityWhichIsDueInTwentyTwentyFive_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment for buyout of development liability which is due in 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Product revenue, net [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product Revenue, Net [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CommitmentsAndContingenciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments And Contingencies [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CommitmentsAndContingenciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments And Contingencies [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CommitmentsAndContingenciesLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Commitments and contingencies.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MaximumNumberOfEmployeesWithEmployersEligibleForRefundableTaxCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum number of employees with employers eligible for refundable tax credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MaximumNumberOfEmployeesWithEmployersEligibleForRefundableTaxCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maximum Number of Employees with Employers Eligible for Refundable Tax Credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MaximumNumberOfEmployeesWithEmployersEligibleForRefundableTaxCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Maximum number of employees with employers eligible for refundable tax credit.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentRedemptionPricePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redemption price, percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentRedemptionPricePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Redemption Price, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TypeOfAdoptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounting Standards Update</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TypeOfAdoptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentQuarterlyReport_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Quarterly Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentQuarterlyReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Quarterly Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total cash, cash equivalents, and restricted cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Cash, cash equivalents and restricted cash at beginning of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Cash, cash equivalents and restricted cash at end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BalanceSheetLocationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Balance Sheet Location</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BalanceSheetLocationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Financial Position Location, Balance [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statistical Measurement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentPaymentTerms_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument, due and payment description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentPaymentTerms_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Payment Terms</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total Financial Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Fair Value Disclosure</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsFairValueDisclosure_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Assets, Fair Value Disclosure, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related and Nonrelated Parties [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Disaggregation of Product Revenue by Major Source</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisaggregationOfRevenueTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Disaggregation of Revenue [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RegulatoryMilestoneIncurredBasedOnAchievement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Regulatory milestone incurred</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RegulatoryMilestoneIncurredBasedOnAchievement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Regulatory milestone incurred based on achievement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RegulatoryMilestoneIncurredBasedOnAchievement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Regulatory Milestone Incurred Based On Achievement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_LicensingAndOtherRevenueMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Licensing and other revenue [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_LicensingAndOtherRevenueMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Licensing And Other Revenue [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_LicensingAndOtherRevenueMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Licensing and other revenue.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Continuing Operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Threshold consecutive trading days</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Long-Term Debt Instruments [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SyfovreMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">SYFOVRE [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SyfovreMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">SYFOVRE [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SyfovreMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Syfovre.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Recently Issued Accounting Standards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">New Accounting Pronouncements, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCityOrTown_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, City or Town</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCityOrTown_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, City or Town</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Total Accumulated Other Comprehensive Income (Loss) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">AOCI Attributable to Parent [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated Other Comprehensive Loss [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementBusinessSegmentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segments [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AvailableInitialDrawAmountUnderCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Available Initial Draw Amount Under Credit Facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AvailableInitialDrawAmountUnderCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Available initial draw amount under credit facility.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AvailableInitialDrawAmountUnderCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Available initial draw amount under credit facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFaceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Principal amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFaceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Face Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DepositsAndOtherCurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deposits and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DepositsAndOtherCurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deposits and Other Current Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DepositsAndOtherCurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deposits and other current assets.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingStandardsUpdate202006Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ASU 2020-06 [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Depreciation, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Depreciation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Income (Loss) Attributable to Parent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Numerator:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Segment Reporting Information, by Segment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DevelopmentCostReimbursementReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Development cost reimbursement received.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DevelopmentCostReimbursementReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Development Cost Reimbursement Received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DevelopmentCostReimbursementReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Development cost reimbursement received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleTermsOfConversionFeature_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Terms of conversion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleTermsOfConversionFeature_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Terms of Conversion Feature</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrivatePlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Private Placement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrivatePlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Private Offering [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PrepaidAndOtherCurrentAssetsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid and Other Current Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PrepaidAndOtherCurrentAssetsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid and Other Current Assets [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PrepaidAndOtherCurrentAssetsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Prepaid and other current assets.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expense and Other Assets, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ValuationAndQualifyingAccountsDisclosureLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingCodmIndividualTitleAndPositionOrGroupOrCommitteeNameExtensibleEnumeration_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueDisclosuresAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Disclosures [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock upon exercise of stock options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Stock Options Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product Sales Receivable [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_EmpaveliPegcetacoplanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">EMPAVELI [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_EmpaveliPegcetacoplanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">EMPAVELI (Pegcetacoplan) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_EmpaveliPegcetacoplanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Empaveli (Pegcetacoplan).</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentType_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Document Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentType_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounting Standards Update</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_Security12bTitle_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Security 12b Title</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_Security12bTitle_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title of 12(b) Security</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Cash and Cash Equivalents, at Carrying Value, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Cash and Cash Equivalents, at Carrying Value, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cash and Cash Equivalents, at Carrying Value, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents, at Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BalanceSheetLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Balance Sheet Location</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BalanceSheetLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Financial Position Location, Balance [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Stockholders' Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Fiscal Period Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Period Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Research and Development Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Payments of employee tax withholding related to equity-based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment, Tax Withholding, Share-Based Payment Arrangement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_IncreaseDecreaseInRightOfUseAssetsAndLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase Decrease In Right-Of-Use Assets And Lease Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_IncreaseDecreaseInRightOfUseAssetsAndLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase (decrease) in right-of-use assets and lease liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_IncreaseDecreaseInRightOfUseAssetsAndLeaseLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Right-of-use assets and lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset Class</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Class [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_UpfrontPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Upfront payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_UpfrontPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Upfront Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_UpfrontPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Upfront payment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DebtInstrumentConvertibleInitialConversionCapPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Initial cap price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DebtInstrumentConvertibleInitialConversionCapPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Convertible Initial Conversion Cap Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DebtInstrumentConvertibleInitialConversionCapPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt Instrument, convertible, initial conversion cap price.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationAllowancesAndReservesTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">SEC Schedule, 12-09, Valuation Allowances and Reserves Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ASinclairDunlopMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">A Sinclair Dunlop [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ASinclairDunlopMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">A Sinclair Dunlop.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_InternalResearchAndDevelopmentCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Internal Research and Development Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_InternalResearchAndDevelopmentCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Internal research and development costs.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsNoncurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-current assets:</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsidiarySaleOfStockAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of Stock</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investing Activities</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MarketableSecuritiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Marketable Securities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total Product revenue, net</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ReceivableFromCollaborationAgreementCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Receivable from collaboration agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ReceivableFromCollaborationAgreementCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Receivable from Collaboration Agreement Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ReceivableFromCollaborationAgreementCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Receivable from collaboration agreement current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DebtInstrumentNumberOfCounterparties_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of counterparties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DebtInstrumentNumberOfCounterparties_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Number Of Counterparties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DebtInstrumentNumberOfCounterparties_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt instrument number of counterparties.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ScheduleOfInterestExpenseRelatedToDebtInstrumentsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Interest Expense Recognized Related to Convertible Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ScheduleOfInterestExpenseRelatedToDebtInstrumentsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Interest Expense Related To Debt Instruments [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ScheduleOfInterestExpenseRelatedToDebtInstrumentsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of interest expense related to debt instruments.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VehiclesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vehicles [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VehiclesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Vehicles [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingGeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Selling, General and Administrative Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingGeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Selling, General and Administrative Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingGeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Selling, general and administrative</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditFacilityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Credit Facility [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeLicenseAgreementPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">license agreement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeLicenseAgreementPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative License Agreement Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeLicenseAgreementPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaborative license agreement payable.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFrequencyOfPeriodicPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument, frequency of periodic payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFrequencyOfPeriodicPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Frequency of Periodic Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Accrued Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (Decrease) in Accounts Payable, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accounts Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liabilities and Stockholders' Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRevenueByMajorCustomersByReportingSegmentsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Customer Accounted for 10% of More of Gross Product Revenues and Accounts Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRevenueByMajorCustomersByReportingSegmentsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentPeriodEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Period End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentPeriodEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Period End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash provided by financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided by (Used in) Financing Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeBenefitsAndShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee Benefits and Share-Based Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeBenefitsAndShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LitigationSettlementAmountAwardedToOtherParty_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Incurred any cost to defend lawsuits or settle claims</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LitigationSettlementAmountAwardedToOtherParty_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Litigation Settlement, Amount Awarded to Other Party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesNoncurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Noncurrent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesNoncurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdTradingDays_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Threshold trading days</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleThresholdTradingDays_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Threshold Trading Days</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Antidilutive securities excluded from computation of earnings per share, amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">APIC, Share-based Payment Arrangement, Increase for Cost Recognition, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">APIC, Share-Based Payment Arrangement, Increase for Cost Recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtConversionConvertedInstrumentAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Aggregate principal amount converted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtConversionConvertedInstrumentAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible Notes exchanged for common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtConversionConvertedInstrumentAmount1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Conversion, Converted Instrument, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total accrued expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingCodmProfitLossMeasureHowUsedDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income tax expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Income Tax Expense (Benefit), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Income tax expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PercentageOfQualifiedWagesPaidToEmployeesUnderEmployeeRetentionCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Percentage of qualified wages paid to employees under employee retention credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PercentageOfQualifiedWagesPaidToEmployeesUnderEmployeeRetentionCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percentage of Qualified Wages Paid to Employees under Employee Retention Credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PercentageOfQualifiedWagesPaidToEmployeesUnderEmployeeRetentionCredit_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percentage of qualified wages paid to employees under employee retention credit.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_TradingSymbol_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Trading Symbol</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_TradingSymbol_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trading Symbol</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_UniversityOfPennsylvaniaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">University of Pennsylvania [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_UniversityOfPennsylvaniaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">University Of Pennsylvania [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_UniversityOfPennsylvaniaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">University of pennsylvania.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VariableRateAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Variable Rate [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impact of adoption of ASU 2020-06</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total stockholders' equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity, Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CustomerAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Customer A.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CustomerAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer A [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CustomerAMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer A [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-Lived Tangible Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Lived Tangible Asset [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Liabilities, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Liabilities, Noncurrent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleConversionPrice1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleConversionPrice1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Conversion Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementUpfrontMilestoneAmountPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement Upfront Milestone Amount Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementUpfrontMilestoneAmountPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaborative arrangement upfront milestone amount payable.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementUpfrontMilestoneAmountPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Upfront milestone payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockUnitsRSUMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock Units (RSUs) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockUnitsRSUMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unvested restricted stock units</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInDeferredRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInDeferredRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Deferred Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MinimumRequiredConvertibleUnsecuredNotesForAdditionalLoanAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum Required Convertible Unsecured Notes for Additional Loan Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MinimumRequiredConvertibleUnsecuredNotesForAdditionalLoanAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Minimum required convertible unsecured notes for additional loan amount.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MinimumRequiredConvertibleUnsecuredNotesForAdditionalLoanAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum required convertible unsecured notes for additional loan amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateAdopted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Change in accounting principle accounting standards update adopted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateAdopted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Change in Accounting Principle, Accounting Standards Update, Adopted [true false]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CustomerCMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer C [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CustomerCMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer C [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CustomerCMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Customer C.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NatureOfOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Nature of Organization and Operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NatureOfOperations_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Nature of Operations [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReportableSegmentAggregationBeforeOtherOperatingSegmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reported Segment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReportableSegmentAggregationBeforeOtherOperatingSegmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reportable Segment, Aggregation before Other Operating Segment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_BachemMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Bachem [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_BachemMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Bachem Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_BachemMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Bachem member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpenseDebtAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Expense, Debt [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CappedCallTransactionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Capped Call Transactions [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CappedCallTransactionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Capped Call Transaction [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CappedCallTransactionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Capped call transaction.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UseOfEstimates_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Use of Estimates</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UseOfEstimates_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Use of Estimates, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskPercentage1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Concentration risk</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskPercentage1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk, Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_JamesChopasMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">James Chopas [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_JamesChopasMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">James Chopas.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherCommitment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other Commitment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherCommitment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Commitment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherCommitment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Commitment, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherCommitment_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Other non-cancellable purchase commitments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StatementScenarioAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Scenario</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_StatementScenarioAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Scenario [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementThirdPartyLicenseExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement Third Party License Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementThirdPartyLicenseExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaborative arrangement third party license expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementThirdPartyLicenseExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Third party license expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Security Exchange Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Security Exchange Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RepurchaseAgreementCounterpartyNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Counterparty Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RepurchaseAgreementCounterpartyNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Counterparty Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value by Liability Class</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value by Liability Class [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total operating expenses:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-Lived Tangible Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Lived Tangible Asset [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ExternalCommercialCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">External commercial costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ExternalCommercialCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">External Commercial Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ExternalCommercialCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">External commercial costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueDisclosuresTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Measurements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueDisclosuresTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Disclosures [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProceedsFromSettlementOfCappedCall_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Proceeds from settlement of capped call.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProceedsFromSettlementOfCappedCall_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds From Settlement Of Capped Call</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProceedsFromSettlementOfCappedCall_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from settlement of capped call</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maximum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities and stockholders' equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RoyaltiesReceivableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Royalties receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RoyaltiesReceivableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalties Receivable Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RoyaltiesReceivableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalties receivable current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Right-of-use assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Right-of-Use Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Right-of-use assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expense, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total prepaid assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net loss per common share, diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net loss per common share, diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Hierarchy and NAV</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Hierarchy and NAV [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided by (Used in) Investing Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash used in investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MinimumRequiredSalesToDrawAdditionalLoanUnderCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum Required Sales to Draw Additional Loan Under Credit Facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MinimumRequiredSalesToDrawAdditionalLoanUnderCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Minimum required sales to draw additional loan under credit facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MinimumRequiredSalesToDrawAdditionalLoanUnderCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum required sales to draw additional loan under credit facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_VolumeWeightedAveragePricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Volume-weighted average price per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_VolumeWeightedAveragePricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Volume Weighted Average Price Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_VolumeWeightedAveragePricePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Volume Weighted Average Price Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementUpFrontPaymentInNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaborative arrangement, up-front payment in next twelve months.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementUpFrontPaymentInNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement Up Front Payment In Next Twelve Months</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementUpFrontPaymentInNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Up-front payment on first anniversary of agreement on June 30, 2022</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ScenarioForecastMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Forecast [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ScenarioForecastMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Forecast [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefits_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Unrecognized Tax Benefits, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefits_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Unrecognized Tax Benefits, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefits_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrecognized tax benefits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AmendedAndRestatedPatentLicenseAgreementWithPennOphthalmicFieldOfUseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amended and Restated Patent License Agreement With Penn (Ophthalmic Field of Use) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AmendedAndRestatedPatentLicenseAgreementWithPennOphthalmicFieldOfUseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amended and Restated Patent License Agreement with Penn (Ophthalmic Field of Use.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AmendedAndRestatedPatentLicenseAgreementWithPennOphthalmicFieldOfUseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amended and Restated Patent License Agreement with Penn (Ophthalmic Field of Use) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFilerCategory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Filer Category</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFilerCategory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Filer Category</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtConversionConvertedInstrumentSharesIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate principal amount converted into shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtConversionConvertedInstrumentSharesIssued1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Conversion, Converted Instrument, Shares Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PaymentForBuyoutOfDevelopmentLiabilityElimination_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment for Buyout of Development Liability Elimination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PaymentForBuyoutOfDevelopmentLiabilityElimination_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment for buyout of development liability elimination.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PaymentForBuyoutOfDevelopmentLiabilityElimination_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment for buyout of development liability elimination</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AlecMachielsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Alec Machiels [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AlecMachielsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Alec Machiels.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AccountsReceivableRemainedOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable Remained Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AccountsReceivableRemainedOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accounts receivable remained outstanding.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AccountsReceivableRemainedOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Outstanding amount of sold accounts receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current Fiscal Year End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current Fiscal Year End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Share-based Payment Arrangement, Noncash Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Noncash Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related and Nonrelated Parties [Axis]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityRegistrantName_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Registrant Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityRegistrantName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Registrant Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share [Text Block]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Maturity Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Credit facility maturity date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityEmergingGrowthCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Emerging Growth Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityEmergingGrowthCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Emerging Growth Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenuesAccountsReceivableAndReservesForProductSalesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product Revenues Accounts Receivable And Reserves For Product Sales [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenuesAccountsReceivableAndReservesForProductSalesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Product revenues, accounts receivable, and reserves for product sales.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AccretionOfDiscountToDevelopmentLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accretion of discount to development liability</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AccretionOfDiscountToDevelopmentLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accretion of discount to development liability.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DownPaymentsForInventoryCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Down payments for inventory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DownPaymentsForInventoryCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Down Payments for Inventory Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DownPaymentsForInventoryCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Down payments for inventory current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingStandardsUpdate201613Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ASU 2016-13 [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MoneyMarketFundsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Money Market Funds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Basic</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CommercialCostsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commercial costs</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CommercialCostsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Commercial costs current.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TransferOfFinancialAssetsAccountedForAsSalesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Transfer of Financial Assets Accounted for as Sales [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TransferOfFinancialAssetsAccountedForAsSalesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Factoring of Accounts Receivable and Associated Fees</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MarkDelongMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Mark DeLong [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MarkDelongMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Mark DeLong.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_NumberOfLicensedProducts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of licensed products</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_NumberOfLicensedProducts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Number Of Licensed Products</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_NumberOfLicensedProducts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Number of licensed products.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ContraResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contract research and development expense</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ContraResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contra research and development expense.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from issuance of common stock, net of issuance costs</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Level 1 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, Inputs, Level 1 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockValueSharesIssuedNetOfTaxWithholdings_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vesting of restricted stock units, net of shares withheld for taxes</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CallTransactionsRemainingNotionalAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">call transactions remaining notional amount.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CallTransactionsRemainingNotionalAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">call transactions remaining notional amount</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SobiAgreementAndAnotherLicensingTransactionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sobi Agreement and Another Licensing Transaction [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SobiAgreementAndAnotherLicensingTransactionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sobi Agreement And Another Licensing Transaction [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SobiAgreementAndAnotherLicensingTransactionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sobi agreement and another licensing transaction.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MilestonePaymentReceivedForAchievementOfRegulatoryDevelopmentMilestone_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Milestone payment received for achievement of regulatory development milestone.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MilestonePaymentReceivedForAchievementOfRegulatoryDevelopmentMilestone_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Milestone payment received for achievement of regulatory development milestone</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementUpfrontNonRefundableAmountPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaborative arrangement upfront non-refundable amount payable.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementUpfrontNonRefundableAmountPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement Upfront Non Refundable Amount Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementUpfrontNonRefundableAmountPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Up-front non-refundable payment</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfCollaborativeArrangementsAndNoncollaborativeArrangementTransactionsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_UniversityOfPennsylvaniaLicenseAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">University Of Pennsylvania License Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_UniversityOfPennsylvaniaLicenseAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">University Of Pennsylvania License Agreements.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_UniversityOfPennsylvaniaLicenseAgreementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">University of Pennsylvania License Agreements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountingPoliciesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Policies [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermPurchaseCommitmentAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-cancellable purchase commitments</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AllowanceForGovernmentAndOtherRebatesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Government and Other Rebates [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement [Table]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFileNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity File Number</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ContractualInterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Contractual interest expense.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PriorToMarchFifteenTwoThousandAndTwentySixConvertibleMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prior to March 15, 2026 Convertible [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PriorToMarchFifteenTwoThousandAndTwentySixConvertibleMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prior To March Fifteen Two Thousand And Twenty Six Convertible [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PriorToMarchFifteenTwoThousandAndTwentySixConvertibleMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Prior to March Fifteen Two Thousand and Twenty Six Convertible.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfFinancialPositionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Financial Position [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityShellCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Shell Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementTermOfAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Collaborative arrangement, term of agreement.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CollaborativeArrangementTermOfAgreement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaboration agreement term</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Measurement Inputs and Valuation Techniques [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateEffectivePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument effective interest rate</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityTaxIdentificationNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Tax Identification Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityTaxIdentificationNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Tax Identification Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets [Abstract]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCurrentReportingStatus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Current Reporting Status</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SegmentRevenueDeductionsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Segment revenue deductions.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_BachemAndNofCorporationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Bachem and NOF</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_BachemAndNofCorporationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Bachem and NOF Corporation [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ChangeInAccountingPrincipleAccountingStandardsUpdateAdoptionDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Change in accounting principle accounting standards update adoption date</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Preferred Stock, Value, Issued, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Preferred Stock, Value, Issued, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Value, Issued</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DevelopmentCostReimbursement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Development cost reimbursement</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_DevelopmentCostReimbursement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Development cost reimbursement.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_TwoThousandNineteenAndTwoThousandTwentyConvertibleNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Two thousand nineteen and two thousand twenty convertible notes.</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromDebtNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Debt, Net of Issuance Costs</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RevisedAdditionalAvailableDrawAmountUponSatisfactionOfSalesOrMarketCapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Revised additional available draw amount upon Satisfaction of sales or market capitalization.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RevisedAdditionalAvailableDrawAmountUponSatisfactionOfSalesOrMarketCapitalization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revised Additional Available Draw Amount Upon Satisfaction of Sales or Market capitalization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNet_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Inventory</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_JeffreyREiseleMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Jeffrey R Eisele [Member]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByBalanceSheetGroupingTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fair Value By Balance Sheet Grouping [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByBalanceSheetGroupingTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value, by Balance Sheet Grouping [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AccruedPayrollLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued payroll liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AccruedPayrollLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Payroll Liabilities Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AccruedPayrollLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued payroll liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_TimothyESullivanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Timothy E Sullivan [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_TimothyESullivanMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Timothy E Sullivan Member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current portion of lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProceedsFromSaleOfOtherReceivablesNetOfFactoringFees_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds From Sale Of Other Receivables Net Of Factoring Fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProceedsFromSaleOfOtherReceivablesNetOfFactoringFees_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Proceeds from sale of other receivables net of factoring fees.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProceedsFromSaleOfOtherReceivablesNetOfFactoringFees_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash proceeds</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Foreign currency gain (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign currency translation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateStatedPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Convertible notes, interest rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateStatedPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument, stated percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateStatedPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Interest Rate, Stated Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Retained Earnings [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated Deficit [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retained Earnings [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Payments to Acquire Property, Plant, and Equipment, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Purchase of property and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Property, Plant, and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ConvertibleSeniorNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible Senior Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ConvertibleSeniorNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Senior Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ConvertibleSeniorNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Convertible senior notes.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentTransitionReport_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Transition Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentTransitionReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Transition Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SummaryOfInterestExpenseRecognizedRelatedToCreditFacilityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Summary of Interest Expense Recognized Related to Credit Facility [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SummaryOfInterestExpenseRecognizedRelatedToCreditFacilityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Summary of interest expense recognized related to credit facility.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SummaryOfInterestExpenseRecognizedRelatedToCreditFacilityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Interest Expense Recognized Related to Credit Facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ValuationAllowancesAndReservesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">SEC Schedule, 12-09, Valuation Allowances and Reserves [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Security, Excluded EPS Calculation [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MinimumPercentageOfTaxPositionLikelihoodOfBeingRealizedUponExaminationByTaxingAuthorities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum percentage of tax position likelihood of being realized upon examination by taxing authorities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MinimumPercentageOfTaxPositionLikelihoodOfBeingRealizedUponExaminationByTaxingAuthorities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum Percentage Of Tax Position Likelihood Of Being Realized Upon Examination By Taxing Authorities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MinimumPercentageOfTaxPositionLikelihoodOfBeingRealizedUponExaminationByTaxingAuthorities_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Minimum percentage of tax position likelihood of being realized upon examination by taxing authorities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SalesReturnsAndAllowancesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Returns [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SalesReturnsAndAllowancesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sales Returns and Allowances [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less: debit discount and issuance costs, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Less: debt discount and issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_BeamTherapeuticsIncorporationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Beam Therapeutics, Incorporation.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_BeamTherapeuticsIncorporationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Beam Therapeutics Incorporation [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_BeamTherapeuticsIncorporationMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Beam [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCash_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Restricted Cash, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCash_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCash_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Payable and Accrued Liabilities Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PaymentOfConvertibleDebtOfferingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Payment of convertible debt offering expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PaymentOfConvertibleDebtOfferingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment Of Convertible Debt Offering Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PaymentOfConvertibleDebtOfferingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment of convertible debt offering expenses.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AmortizationOfDiscountsForCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization Of Discounts For Credit Facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AmortizationOfDiscountsForCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amortization of discounts for credit facility.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AmortizationOfDiscountsForCreditFacility_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization of discounts for credit facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Noncurrent Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional Paid-In Capital [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Paid-in Capital [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Adjustments to reconcile net loss to net cash used in operating activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Net of Tax [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other comprehensive gain:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Assets, Noncurrent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Assets, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_BachemAmericasIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Bachem Americas, Inc [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_BachemAmericasIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Bachem Americas Inc [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_BachemAmericasIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Bachem Americas Inc.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segments [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherPrepaidExpenseCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other prepaid expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherPrepaidExpenseCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Prepaid Expense, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfInventoryCurrentTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Inventory Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfInventoryCurrentTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Inventory, Current [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Common Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Common Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleConversionRatio1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Conversion ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentConvertibleConversionRatio1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Convertible, Conversion Ratio</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BasisOfAccountingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basis of Presentation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BasisOfAccountingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Basis of Accounting, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ScenarioUnspecifiedDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Scenario</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ScenarioUnspecifiedDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Scenario [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_EquityComponentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity Component [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_EquityComponentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Component [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_EquityComponentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Equity component.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Common Stock, Value, Issued, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Common Stock, Value, Issued, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Common Stock, Value, Issued, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Value, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, $0.0001 par value; 200,000 shares authorized at March 31, 2025 and December 31, 2024; 125,661 shares issued and outstanding at March 31, 2025, and 124,495 shares issued and outstanding at December 31, 2024</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CarolineBaumalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Caroline Baumal [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CarolineBaumalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Caroline Baumal [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenuesAccountsReceivableAndReservesForProductSalesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product Revenues, Accounts Receivable, and Reserves for Product Sales</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenuesAccountsReceivableAndReservesForProductSalesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product Revenues Accounts Receivable And Reserves For Product Sales [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenuesAccountsReceivableAndReservesForProductSalesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Product revenues, accounts receivable, and reserves for product sales.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_WaivedPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Waived Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_WaivedPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Waived payment.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_WaivedPayment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Waived Payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CedricFrancoisMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cedric Francois [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CedricFrancoisMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cedric Francois.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenuesAccountsReceivableAndReservesForProductSalesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product Revenues Accounts Receivable And Reserves For Product Sales [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenuesAccountsReceivableAndReservesForProductSalesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product Revenues Accounts Receivable And Reserves For Product Sales [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ProductRevenuesAccountsReceivableAndReservesForProductSalesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Product revenues, accounts receivable, and reserves for product sales.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AssetBasedFinancingArrangementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset-Based Financing Arrangement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AssetBasedFinancingArrangementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset-based financing arrangement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByMeasurementFrequencyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Measurement Frequency</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByMeasurementFrequencyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Frequency [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Accrued Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Accrued Liabilities [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and contingencies (Note 11)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">New Accounting Pronouncements or Change in Accounting Principle [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxesPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash paid for income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxesPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Taxes Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AccruedLiabilitiesCurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued Expenses [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AccruedLiabilitiesCurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Liabilities Current [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_AccruedLiabilitiesCurrentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued liabilities, current.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Weighted-average number of common shares used in net loss per common share, diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Weighted-average number of common shares used in net loss per common share, diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible senior notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConvertibleDebtNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Debt, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Segment Reporting Information, by Segment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of segment financial information</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EntityWideRevenueMajorCustomerLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue, Major Customer [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EntityWideRevenueMajorCustomerLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue, Major Customer [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accounts Receivable, after Allowance for Credit Loss, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, after Allowance for Credit Loss, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInInventories_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (Decrease) in Inventories, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInInventories_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Inventory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInInventories_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Inventories</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MinimumRequiredFinancialCovenantIfCapitalizationBelowThreeBillion_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum Required Financial Covenant if Capitalization Below Three Billion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MinimumRequiredFinancialCovenantIfCapitalizationBelowThreeBillion_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Minimum required financial covenant if capitalization below three billion.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_MinimumRequiredFinancialCovenantIfCapitalizationBelowThreeBillion_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum required financial covenant if capitalization below three billion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Diluted [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Denominator:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskBenchmarkDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk Benchmark [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SublicenseFeeOwed_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sublicense fee owed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SublicenseFeeOwed_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sublicense Fee Owed</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SublicenseFeeOwed_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Sublicense fee owed.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntitySmallBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Small Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntitySmallBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Small Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingInformationLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting Information [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Basis Spread on Variable Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Variable interest rate percentage on base rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ConvertibleNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Convertible Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ConvertibleNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Convertible notes.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ConvertibleNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Convertible notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RoyaltyRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Royalty revenue.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RoyaltyRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Royalty Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_RoyaltyRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Royalty revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Revenues_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Revenues_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Revenues, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Revenues_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PaymentOfFactoringFees_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payment of factoring fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PaymentOfFactoringFees_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Payment of factoring fees.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_PaymentOfFactoringFees_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less: factoring fees</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_OperatingCostOfSales_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cost of sales</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_OperatingCostOfSales_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Cost Of Sales</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_OperatingCostOfSales_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Operating cost of sales.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounting Standards Update and Change in Accounting Principle [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditFacilityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Credit Facility [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractualObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total future minimum payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractualObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate milestones payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractualObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Obligated to pay initial payment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractualObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contractual Obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentRedemptionPeriodStartDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Redemption period, start date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentRedemptionPeriodStartDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Redemption Period, Start Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Financing Activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided by (Used in) Financing Activities [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SwedishOrphanBiovitrumABPublMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Swedish Orphan Biovitrum A B Publ [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SwedishOrphanBiovitrumABPublMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Swedish Orphan Biovitrum AB (Publ) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_SwedishOrphanBiovitrumABPublMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Swedish Orphan Biovitrum AB (Publ).</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ResearchCollaborationAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Research collaboration agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ResearchCollaborationAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research Collaboration Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_ResearchCollaborationAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research Collaboration Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByAssetClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset Class</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueByAssetClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Class [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CommitmentsAndContingenciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments And Contingencies [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CommitmentsAndContingenciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments And Contingencies [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="apls_CommitmentsAndContingenciesTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Commitments And Contingencies [Table]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueMeasurementFrequencyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Measurement Frequency [Domain]</link:label>
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          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_InterestExpenseDebt" xlink:to="us-gaap_AmortizationOfFinancingCosts" order="1" weight="1" use="optional"/>
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_InterestExpenseDebt" xlink:to="apls_ContractualInterestExpense" order="2" weight="1" use="optional"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseDebt" xlink:label="us-gaap_InterestExpenseDebt"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_AmortizationOfFinancingCosts" xlink:label="us-gaap_AmortizationOfFinancingCosts"/>
          <link:loc xlink:type="locator" xlink:href="apls-20250331.xsd#apls_ContractualInterestExpense" xlink:label="apls_ContractualInterestExpense"/>
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        <link:calculationLink xlink:type="extended" xlink:role="http://www.apellis.com/20250331/taxonomy/role/DisclosureLongtermDebtSummaryOfCreditFacilityDetail">
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LongTermDebt" xlink:to="us-gaap_DebtInstrumentCarryingAmount" order="0" weight="1" use="optional"/>
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LongTermDebt" xlink:to="us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet" order="1" weight="-1" use="optional"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_LongTermDebt" xlink:label="us-gaap_LongTermDebt"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentCarryingAmount" xlink:label="us-gaap_DebtInstrumentCarryingAmount"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet"/>
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        <link:calculationLink xlink:type="extended" xlink:role="http://www.apellis.com/20250331/taxonomy/role/DisclosureLongTermDebtSummaryOfInterestExpenseRecognizedRelatedToCreditFacilityDetail">
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_InterestExpenseDebt" xlink:to="us-gaap_AmortizationOfFinancingCosts" order="1" weight="1" use="optional"/>
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_InterestExpenseDebt" xlink:to="apls_ContractualInterestExpense" order="2" weight="1" use="optional"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_InterestExpenseDebt" xlink:label="us-gaap_InterestExpenseDebt"/>
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          <link:loc xlink:type="locator" xlink:href="apls-20250331.xsd#apls_ContractualInterestExpense" xlink:label="apls_ContractualInterestExpense"/>
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  <xsd:element id="apls_BachemAndNofCorporationMember" name="BachemAndNofCorporationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_DebtInstrumentConvertibleInitialConversionPrice" name="DebtInstrumentConvertibleInitialConversionPrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="apls_ProductSalesReserves" name="ProductSalesReserves" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_AmortizationOfDiscountsForCreditFacility" name="AmortizationOfDiscountsForCreditFacility" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_DavidWatsonMember" name="DavidWatsonMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_AvailableAdditionalDrawAmountUponSatisfactionOfCashRequirements" name="AvailableAdditionalDrawAmountUponSatisfactionOfCashRequirements" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_RegulatoryMilestoneIncurredBasedOnAchievement" name="RegulatoryMilestoneIncurredBasedOnAchievement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_SFJAgreementMember" name="SFJAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_ProductRevenueReservesCurrent" name="ProductRevenueReservesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_ASinclairDunlopMember" name="ASinclairDunlopMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_ProductRevenuesAccountsReceivableAndReservesForProductSalesAbstract" name="ProductRevenuesAccountsReceivableAndReservesForProductSalesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_DebtInstrumentConvertibleThresholdTradingPricePerPrincipalAmount" name="DebtInstrumentConvertibleThresholdTradingPricePerPrincipalAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_UpfrontPayment" name="UpfrontPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_InternalSellingGeneralAndAdministrativeCost" name="InternalSellingGeneralAndAdministrativeCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_MinimumRequiredFinancialCovenantIfCapitalizationBelowThreeBillion" name="MinimumRequiredFinancialCovenantIfCapitalizationBelowThreeBillion" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_SummaryOfInterestExpenseRecognizedRelatedToCreditFacilityTableTextBlock" name="SummaryOfInterestExpenseRecognizedRelatedToCreditFacilityTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="apls_LicensingAndOtherRevenueMember" name="LicensingAndOtherRevenueMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_AccruedPayrollLiabilitiesCurrent" name="AccruedPayrollLiabilitiesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_CarolineBaumalMember" name="CarolineBaumalMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_SegmentRevenueDeductionsAbstract" name="SegmentRevenueDeductionsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_EquityComponentMember" name="EquityComponentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_UniversityOfPennsylvaniaMember" name="UniversityOfPennsylvaniaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_ExcerciseOptionDrawAmountUnderCreditFacility" name="ExcerciseOptionDrawAmountUnderCreditFacility" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_PatentLicenseAgreementWithPennNon-OphthalmicFieldsOfUseMember" name="PatentLicenseAgreementWithPennNon-OphthalmicFieldsOfUseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_PriorToMarchFifteenTwoThousandAndTwentySixConvertibleMember" name="PriorToMarchFifteenTwoThousandAndTwentySixConvertibleMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_PaymentOfFactoringFees" name="PaymentOfFactoringFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_ProductRevenueAllowancesAndReservesCreditAndPaymentsMade" name="ProductRevenueAllowancesAndReservesCreditAndPaymentsMade" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_ProductRevenueAllowancesAndReservesProvisionRelatedToSalesInTheCurrentYear" name="ProductRevenueAllowancesAndReservesProvisionRelatedToSalesInTheCurrentYear" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_CollaborativeArrangementThirdPartyLicenseExpenses" name="CollaborativeArrangementThirdPartyLicenseExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_AmendedAndRestatedPatentLicenseAgreementWithPennOphthalmicFieldOfUseMember" name="AmendedAndRestatedPatentLicenseAgreementWithPennOphthalmicFieldOfUseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_InternalResearchAndDevelopmentCosts" name="InternalResearchAndDevelopmentCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_CommercialCostsCurrent" name="CommercialCostsCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_SublicenseFeeOwed" name="SublicenseFeeOwed" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_IncreaseDecreaseInRightOfUseAssetsAndLeaseLiabilities" name="IncreaseDecreaseInRightOfUseAssetsAndLeaseLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_PercentageOfPrepaymentPremiumUnderCreditFacility" name="PercentageOfPrepaymentPremiumUnderCreditFacility" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="apls_MaximumCreditPerEmployeeForEachCalendarQuarter" name="MaximumCreditPerEmployeeForEachCalendarQuarter" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_PaymentForBuyoutOfDevelopmentLiabilityWhichIsDueInTwentyTwentyFive" name="PaymentForBuyoutOfDevelopmentLiabilityWhichIsDueInTwentyTwentyFive" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_RefundFiledUnderCaresActRelatingToEmployeeRetentionCredit" name="RefundFiledUnderCaresActRelatingToEmployeeRetentionCredit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_AllowanceForChargebacksDiscountsAndFeesMember" name="AllowanceForChargebacksDiscountsAndFeesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_PaymentForBuyoutOfDevelopmentLiabilityElimination" name="PaymentForBuyoutOfDevelopmentLiabilityElimination" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_ExternalGeneralAndAdministrativeCosts" name="ExternalGeneralAndAdministrativeCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_TwoThousandNineteenConvertibleNotesAndTwoThousandTwentyConvertibleNotesMember" name="TwoThousandNineteenConvertibleNotesAndTwoThousandTwentyConvertibleNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_ProductRevenueAllowancesAndReservesAdjustmentsRelatedToPriorPeriodSales" name="ProductRevenueAllowancesAndReservesAdjustmentsRelatedToPriorPeriodSales" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_NurNicholsonMember" name="NurNicholsonMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_AccretionOfDiscountToDevelopmentLiability" name="AccretionOfDiscountToDevelopmentLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_ProductRevenueReservesAndAllowancesTableTextBlock" name="ProductRevenueReservesAndAllowancesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="apls_ProductRevenuesAccountsReceivableAndReservesForProductSalesTextBlock" name="ProductRevenuesAccountsReceivableAndReservesForProductSalesTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="apls_RegulatoryMilestonePaymentsBasedOnAchievement" name="RegulatoryMilestonePaymentsBasedOnAchievement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_AspaveliMember" name="AspaveliMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_SixthStreetFinancingAgreementMember" name="SixthStreetFinancingAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_Inventory" name="Inventory" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_ReceivableFromCollaborationAgreementCurrent" name="ReceivableFromCollaborationAgreementCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_ProceedsFromSettlementOfCappedCall" name="ProceedsFromSettlementOfCappedCall" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_CustomerDMember" name="CustomerDMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_MarketCapitalizationThresholdForCreditFacility" name="MarketCapitalizationThresholdForCreditFacility" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_NumberOfLicensedProducts" name="NumberOfLicensedProducts" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="apls_PaymentOfConvertibleDebtOfferingExpenses" name="PaymentOfConvertibleDebtOfferingExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_ConvertibleNotesMember" name="ConvertibleNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_AccruedLiabilitiesCurrentMember" name="AccruedLiabilitiesCurrentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_ExchangeAgreementsMember" name="ExchangeAgreementsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_ScheduleOfInterestExpenseRelatedToDebtInstrumentsTableTextBlock" name="ScheduleOfInterestExpenseRelatedToDebtInstrumentsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="apls_ConvertibleSeniorNotesNoncurrent" name="ConvertibleSeniorNotesNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_ProductRevenuesAccountsReceivableAndReservesForProductSalesLineItems" name="ProductRevenuesAccountsReceivableAndReservesForProductSalesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_RoyaltiesEntitledToReceiveAfterFirstCommercialSaleOfApplicableLicensedProductPeriod" name="RoyaltiesEntitledToReceiveAfterFirstCommercialSaleOfApplicableLicensedProductPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="apls_CollaborativeArrangementMaximumExtendableTermOfAgreement" name="CollaborativeArrangementMaximumExtendableTermOfAgreement" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="apls_DebtInstrumentConvertibleInitialConversionCapPrice" name="DebtInstrumentConvertibleInitialConversionCapPrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="apls_EmpaveliAndAspaveliMember" name="EmpaveliAndAspaveliMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_ExternalCommercialCosts" name="ExternalCommercialCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_MinimumCashRequirementsToDrawAdditionalLoanUnderCreditFacility" name="MinimumCashRequirementsToDrawAdditionalLoanUnderCreditFacility" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_ProceedsFromSaleOfOtherReceivablesNetOfFactoringFees" name="ProceedsFromSaleOfOtherReceivablesNetOfFactoringFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_SobiAgreementAndAnotherLicensingTransactionMember" name="SobiAgreementAndAnotherLicensingTransactionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_DownPaymentsForInventoryCurrent" name="DownPaymentsForInventoryCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_CappedCallTransactionMember" name="CappedCallTransactionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_CustomerCMember" name="CustomerCMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_AccountsReceivableRemainedOutstanding" name="AccountsReceivableRemainedOutstanding" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_LiabilityComponentMember" name="LiabilityComponentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_AvailableInitialDrawAmountUnderCreditFacility" name="AvailableInitialDrawAmountUnderCreditFacility" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_PercentageOfQualifiedWagesPaidToEmployeesUnderEmployeeRetentionCredit" name="PercentageOfQualifiedWagesPaidToEmployeesUnderEmployeeRetentionCredit" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="apls_AssetBasedFinancingArrangementMember" name="AssetBasedFinancingArrangementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_CollaborativeLicenseAgreementPayable" name="CollaborativeLicenseAgreementPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_ConvertibleSeniorNotesMember" name="ConvertibleSeniorNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_CollaborativeArrangementUpFrontPaymentInNextTwelveMonths" name="CollaborativeArrangementUpFrontPaymentInNextTwelveMonths" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="apls_MaximumNumberOfEmployeesWithEmployersEligibleForRefundableTaxCredit" name="MaximumNumberOfEmployeesWithEmployersEligibleForRefundableTaxCredit" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="apls_MarketCapitalizationThresholdPercentageForCreditFacility" name="MarketCapitalizationThresholdPercentageForCreditFacility" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="apls_PrepaidResearchAndDevelopmentCurrent" name="PrepaidResearchAndDevelopmentCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_CollaborativeArrangementTermOfAgreement" name="CollaborativeArrangementTermOfAgreement" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="apls_VolumeWeightedAveragePricePerShare" name="VolumeWeightedAveragePricePerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="apls_RoyaltiesReceivableCurrent" name="RoyaltiesReceivableCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_AmortizationOfDiscountsForConvertibleNotes" name="AmortizationOfDiscountsForConvertibleNotes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_ContraResearchAndDevelopmentExpense" name="ContraResearchAndDevelopmentExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_ContractualInterestExpense" name="ContractualInterestExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_DevelopmentMilestoneAchievement" name="DevelopmentMilestoneAchievement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_MarkDelongMember" name="MarkDelongMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_ConvertibleNotesHeldInTreasury" name="ConvertibleNotesHeldInTreasury" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_DevelopmentCostReimbursementReceived" name="DevelopmentCostReimbursementReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_OperatingCostOfSales" name="OperatingCostOfSales" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_ResearchCollaborationAgreementMember" name="ResearchCollaborationAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_CustomerAMember" name="CustomerAMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_CommitmentsAndContingenciesTable" name="CommitmentsAndContingenciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_ProceedsFromInitialDrawAmountUnderCreditFacility" name="ProceedsFromInitialDrawAmountUnderCreditFacility" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_AlecMachielsMember" name="AlecMachielsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_CollaborativeArrangementUpfrontNonRefundableAmountPayable" name="CollaborativeArrangementUpfrontNonRefundableAmountPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_MinimumRequiredConvertibleUnsecuredNotesForAdditionalLoanAmount" name="MinimumRequiredConvertibleUnsecuredNotesForAdditionalLoanAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_TimothySullivanMember" name="TimothySullivanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_AggregateMilestonePaymentsUponAchievementOfSpecifiedOneTimeRegulatoryDevelopmentAndCommercialMilestoneEvents" name="AggregateMilestonePaymentsUponAchievementOfSpecifiedOneTimeRegulatoryDevelopmentAndCommercialMilestoneEvents" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_AllowanceForGovernmentAndOtherRebatesMember" name="AllowanceForGovernmentAndOtherRebatesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_ProductRevenueAllowancesAndReserves" name="ProductRevenueAllowancesAndReserves" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_WaivedPayment" name="WaivedPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_EmpaveliPegcetacoplanMember" name="EmpaveliPegcetacoplanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_ProductRevenuesAccountsReceivableAndReservesForProductSalesTable" name="ProductRevenuesAccountsReceivableAndReservesForProductSalesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_TwoThousandNineteenAndTwoThousandTwentyConvertibleNotesMember" name="TwoThousandNineteenAndTwoThousandTwentyConvertibleNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_CallTransactionsRemainingNotionalAmount" name="CallTransactionsRemainingNotionalAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAbstract" name="ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_PrepaidAndOtherCurrentAssetsTextBlock" name="PrepaidAndOtherCurrentAssetsTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="apls_RevisedAdditionalAvailableDrawAmountUponSatisfactionOfSalesOrMarketCapitalization" name="RevisedAdditionalAvailableDrawAmountUponSatisfactionOfSalesOrMarketCapitalization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_CedricFrancoisMember" name="CedricFrancoisMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_BachemAmericasIncMember" name="BachemAmericasIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_MinimumPercentageOfTaxPositionLikelihoodOfBeingRealizedUponExaminationByTaxingAuthorities" name="MinimumPercentageOfTaxPositionLikelihoodOfBeingRealizedUponExaminationByTaxingAuthorities" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="apls_AccruedResearchAndDevelopmentCurrent" name="AccruedResearchAndDevelopmentCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_TwoThousandNineteenConvertibleNotesMember" name="TwoThousandNineteenConvertibleNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_CollaborativeArrangementNumberOfResearchPrograms" name="CollaborativeArrangementNumberOfResearchPrograms" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="apls_CollaborativeArrangementUpfrontMilestoneAmountPayable" name="CollaborativeArrangementUpfrontMilestoneAmountPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_DevelopmentCostReimbursement" name="DevelopmentCostReimbursement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_CreditFacilityMember" name="CreditFacilityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_CommitmentsAndContingenciesLineItems" name="CommitmentsAndContingenciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_MinimumRequiredSalesToDrawAdditionalLoanUnderCreditFacility" name="MinimumRequiredSalesToDrawAdditionalLoanUnderCreditFacility" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_PaymentOfConvertibleDebtDiscountsAndCommissions" name="PaymentOfConvertibleDebtDiscountsAndCommissions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_KarenLLewisMember" name="KarenLLewisMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_ProductRevenueAllowanceAndReservesMember" name="ProductRevenueAllowanceAndReservesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_TwoThousandTwentyConvertibleNotesMember" name="TwoThousandTwentyConvertibleNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_RoyaltyRevenue" name="RoyaltyRevenue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_BeamTherapeuticsIncorporationMember" name="BeamTherapeuticsIncorporationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_JeffreyREiseleMember" name="JeffreyREiseleMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_SyfovreMember" name="SyfovreMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_SalesMilestonePaymentsBasedOnAchievementOfAnnualSalesMilestones" name="SalesMilestonePaymentsBasedOnAchievementOfAnnualSalesMilestones" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_CollaborationAndLicenseAgreementMember" name="CollaborationAndLicenseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_TwoThousandTenLicenseAgreementMember" name="TwoThousandTenLicenseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_DepositsAndOtherCurrentAssets" name="DepositsAndOtherCurrentAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_ExternalResearchAndDevelopmentCosts" name="ExternalResearchAndDevelopmentCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="apls_MilestonePaymentReceivedForAchievementOfRegulatoryDevelopmentMilestone" name="MilestonePaymentReceivedForAchievementOfRegulatoryDevelopmentMilestone" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="apls_BachemMember" name="BachemMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_ConvertibleSeniorNotesDueTwoThousandTwentySixMember" name="ConvertibleSeniorNotesDueTwoThousandTwentySixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_JamesChopasMember" name="JamesChopasMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_SeniorSecuredCreditFacilityMember" name="SeniorSecuredCreditFacilityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_SwedishOrphanBiovitrumABPublMember" name="SwedishOrphanBiovitrumABPublMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_UniversityOfPennsylvaniaLicenseAgreementsMember" name="UniversityOfPennsylvaniaLicenseAgreementsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_TimothyESullivanMember" name="TimothyESullivanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="apls_DebtInstrumentNumberOfCounterparties" name="DebtInstrumentNumberOfCounterparties" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
</xsd:schema>
