3.26.1 html 429 341 1 false 108 0 false 11 false false R1.htm 0000001 - Document - Cover page Sheet http://www.abivax.com/role/Coverpage Cover page Cover 1 false false R2.htm 9952151 - Statement - UNAUDITED INTERIM CONDENSED CONSOLIDATED STATEMENTS OF FINANCIAL POSITION Sheet http://www.abivax.com/role/UNAUDITEDINTERIMCONDENSEDCONSOLIDATEDSTATEMENTSOFFINANCIALPOSITION UNAUDITED INTERIM CONDENSED CONSOLIDATED STATEMENTS OF FINANCIAL POSITION Statements 2 false false R3.htm 9952152 - Statement - UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF LOSS Sheet http://www.abivax.com/role/UNAUDITEDCONDENSEDCONSOLIDATEDSTATEMENTSOFLOSS UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF LOSS Statements 3 false false R4.htm 9952153 - Statement - UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS Sheet http://www.abivax.com/role/UNAUDITEDCONDENSEDCONSOLIDATEDSTATEMENTSOFCOMPREHENSIVELOSS UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS Statements 4 false false R5.htm 9952154 - Statement - UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS’ EQUITY Sheet http://www.abivax.com/role/UNAUDITEDCONDENSEDCONSOLIDATEDSTATEMENTSOFCHANGESINSHAREHOLDERSEQUITY UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS’ EQUITY Statements 5 false false R6.htm 9952155 - Statement - UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS Sheet http://www.abivax.com/role/UNAUDITEDCONDENSEDCONSOLIDATEDSTATEMENTSOFCASHFLOWS UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS Statements 6 false false R7.htm 9952156 - Disclosure - The Group Sheet http://www.abivax.com/role/TheGroup The Group Notes 7 false false R8.htm 9952157 - Disclosure - Basis of preparation Sheet http://www.abivax.com/role/Basisofpreparation Basis of preparation Notes 8 false false R9.htm 9952158 - Disclosure - Significant events for the year ended December 31, 2025 and the three-month period ended March 31, 2026 and subsequent events Sheet http://www.abivax.com/role/SignificanteventsfortheyearendedDecember312025andthethreemonthperiodendedMarch312026andsubsequentevents Significant events for the year ended December 31, 2025 and the three-month period ended March 31, 2026 and subsequent events Notes 9 false false R10.htm 9952159 - Disclosure - Accounting principles Sheet http://www.abivax.com/role/Accountingprinciples Accounting principles Notes 10 false false R11.htm 9952160 - Disclosure - Segment information Sheet http://www.abivax.com/role/Segmentinformation Segment information Notes 11 false false R12.htm 9952161 - Disclosure - Goodwill and impairment test Sheet http://www.abivax.com/role/Goodwillandimpairmenttest Goodwill and impairment test Notes 12 false false R13.htm 9952162 - Disclosure - Intangible assets Sheet http://www.abivax.com/role/Intangibleassets Intangible assets Notes 13 false false R14.htm 9952163 - Disclosure - Property, plant and equipment Sheet http://www.abivax.com/role/Propertyplantandequipment Property, plant and equipment Notes 14 false false R15.htm 9952164 - Disclosure - Other financial assets Sheet http://www.abivax.com/role/Otherfinancialassets Other financial assets Notes 15 false false R16.htm 9952165 - Disclosure - Other receivables and assets Sheet http://www.abivax.com/role/Otherreceivablesandassets Other receivables and assets Notes 16 false false R17.htm 9952166 - Disclosure - Cash and cash equivalents Sheet http://www.abivax.com/role/Cashandcashequivalents Cash and cash equivalents Notes 17 false false R18.htm 9952167 - Disclosure - Financial assets and liabilities Sheet http://www.abivax.com/role/Financialassetsandliabilities Financial assets and liabilities Notes 18 false false R19.htm 9952168 - Disclosure - Shareholders’ equity Sheet http://www.abivax.com/role/Shareholdersequity Shareholders’ equity Notes 19 false false R20.htm 9952169 - Disclosure - Share-based payments Sheet http://www.abivax.com/role/Sharebasedpayments Share-based payments Notes 20 false false R21.htm 9952170 - Disclosure - Financial liabilities Sheet http://www.abivax.com/role/Financialliabilities Financial liabilities Notes 21 false false R22.htm 9952171 - Disclosure - Retirement benefit obligations Sheet http://www.abivax.com/role/Retirementbenefitobligations Retirement benefit obligations Notes 22 false false R23.htm 9952172 - Disclosure - Payables, other current liabilities and provisions Sheet http://www.abivax.com/role/Payablesothercurrentliabilitiesandprovisions Payables, other current liabilities and provisions Notes 23 false false R24.htm 9952173 - Disclosure - Operating income Sheet http://www.abivax.com/role/Operatingincome Operating income Notes 24 false false R25.htm 9952174 - Disclosure - Operating expenses Sheet http://www.abivax.com/role/Operatingexpenses Operating expenses Notes 25 false false R26.htm 9952175 - Disclosure - Employees Sheet http://www.abivax.com/role/Employees Employees Notes 26 false false R27.htm 9952176 - Disclosure - Financial gain (loss) Sheet http://www.abivax.com/role/Financialgainloss Financial gain (loss) Notes 27 false false R28.htm 9952177 - Disclosure - Income tax Sheet http://www.abivax.com/role/Incometax Income tax Notes 28 false false R29.htm 9952178 - Disclosure - Loss per share Sheet http://www.abivax.com/role/Losspershare Loss per share Notes 29 false false R30.htm 9952179 - Disclosure - Related parties Sheet http://www.abivax.com/role/Relatedparties Related parties Notes 30 false false R31.htm 9952180 - Disclosure - Off-balance sheet commitments given and contingent liabilities Sheet http://www.abivax.com/role/Offbalancesheetcommitmentsgivenandcontingentliabilities Off-balance sheet commitments given and contingent liabilities Notes 31 false false R32.htm 9952181 - Disclosure - Off-balance sheet commitments received and contingent assets Sheet http://www.abivax.com/role/Offbalancesheetcommitmentsreceivedandcontingentassets Off-balance sheet commitments received and contingent assets Notes 32 false false R33.htm 9952182 - Disclosure - Management and assessment of financial risks Sheet http://www.abivax.com/role/Managementandassessmentoffinancialrisks Management and assessment of financial risks Notes 33 false false R34.htm 9955511 - Disclosure - Accounting principles (Policies) Sheet http://www.abivax.com/role/AccountingprinciplesPolicies Accounting principles (Policies) Policies http://www.abivax.com/role/Accountingprinciples 34 false false R35.htm 9955512 - Disclosure - Intangible assets (Tables) Sheet http://www.abivax.com/role/IntangibleassetsTables Intangible assets (Tables) Tables http://www.abivax.com/role/Intangibleassets 35 false false R36.htm 9955513 - Disclosure - Property, plant and equipment (Tables) Sheet http://www.abivax.com/role/PropertyplantandequipmentTables Property, plant and equipment (Tables) Tables http://www.abivax.com/role/Propertyplantandequipment 36 false false R37.htm 9955514 - Disclosure - Other financial assets (Tables) Sheet http://www.abivax.com/role/OtherfinancialassetsTables Other financial assets (Tables) Tables http://www.abivax.com/role/Otherfinancialassets 37 false false R38.htm 9955515 - Disclosure - Other receivables and assets (Tables) Sheet http://www.abivax.com/role/OtherreceivablesandassetsTables Other receivables and assets (Tables) Tables http://www.abivax.com/role/Otherreceivablesandassets 38 false false R39.htm 9955516 - Disclosure - Cash and cash equivalents (Tables) Sheet http://www.abivax.com/role/CashandcashequivalentsTables Cash and cash equivalents (Tables) Tables http://www.abivax.com/role/Cashandcashequivalents 39 false false R40.htm 9955517 - Disclosure - Financial assets and liabilities (Tables) Sheet http://www.abivax.com/role/FinancialassetsandliabilitiesTables Financial assets and liabilities (Tables) Tables http://www.abivax.com/role/Financialassetsandliabilities 40 false false R41.htm 9955518 - Disclosure - Share-based payments (Tables) Sheet http://www.abivax.com/role/SharebasedpaymentsTables Share-based payments (Tables) Tables http://www.abivax.com/role/Sharebasedpayments 41 false false R42.htm 9955519 - Disclosure - Financial liabilities (Tables) Sheet http://www.abivax.com/role/FinancialliabilitiesTables Financial liabilities (Tables) Tables http://www.abivax.com/role/Financialliabilities 42 false false R43.htm 9955520 - Disclosure - Payables, other current liabilities and provisions (Tables) Sheet http://www.abivax.com/role/PayablesothercurrentliabilitiesandprovisionsTables Payables, other current liabilities and provisions (Tables) Tables http://www.abivax.com/role/Payablesothercurrentliabilitiesandprovisions 43 false false R44.htm 9955521 - Disclosure - Operating income (Tables) Sheet http://www.abivax.com/role/OperatingincomeTables Operating income (Tables) Tables http://www.abivax.com/role/Operatingincome 44 false false R45.htm 9955522 - Disclosure - Operating expenses (Tables) Sheet http://www.abivax.com/role/OperatingexpensesTables Operating expenses (Tables) Tables http://www.abivax.com/role/Operatingexpenses 45 false false R46.htm 9955523 - Disclosure - Employees (Tables) Sheet http://www.abivax.com/role/EmployeesTables Employees (Tables) Tables http://www.abivax.com/role/Employees 46 false false R47.htm 9955524 - Disclosure - Financial gain (loss) (Tables) Sheet http://www.abivax.com/role/FinancialgainlossTables Financial gain (loss) (Tables) Tables http://www.abivax.com/role/Financialgainloss 47 false false R48.htm 9955525 - Disclosure - Loss per share (Tables) Sheet http://www.abivax.com/role/LosspershareTables Loss per share (Tables) Tables http://www.abivax.com/role/Losspershare 48 false false R49.htm 9955526 - Disclosure - The Group (Details) Sheet http://www.abivax.com/role/TheGroupDetails The Group (Details) Details http://www.abivax.com/role/TheGroup 49 false false R50.htm 9955527 - Disclosure - Basis of preparation (Details) Sheet http://www.abivax.com/role/BasisofpreparationDetails Basis of preparation (Details) Details http://www.abivax.com/role/Basisofpreparation 50 false false R51.htm 9955528 - Disclosure - Significant events for the year ended December 31, 2025 and the three-month period ended March 31, 2026 and subsequent events - For the year ended December 31, 2025 (Details) Sheet http://www.abivax.com/role/SignificanteventsfortheyearendedDecember312025andthethreemonthperiodendedMarch312026andsubsequenteventsFortheyearendedDecember312025Details Significant events for the year ended December 31, 2025 and the three-month period ended March 31, 2026 and subsequent events - For the year ended December 31, 2025 (Details) Details 51 false false R52.htm 9955529 - Disclosure - Significant events for the year ended December 31, 2025 and the three-month period ended March 31, 2026 and subsequent events - For the three-month period ended March 31, 2026 (Details) Sheet http://www.abivax.com/role/SignificanteventsfortheyearendedDecember312025andthethreemonthperiodendedMarch312026andsubsequenteventsForthethreemonthperiodendedMarch312026Details Significant events for the year ended December 31, 2025 and the three-month period ended March 31, 2026 and subsequent events - For the three-month period ended March 31, 2026 (Details) Details 52 false false R53.htm 9955530 - Disclosure - Significant events for the year ended December 31, 2025 and the three-month period ended March 31, 2026 and subsequent events - Subsequent events (Details) Sheet http://www.abivax.com/role/SignificanteventsfortheyearendedDecember312025andthethreemonthperiodendedMarch312026andsubsequenteventsSubsequenteventsDetails Significant events for the year ended December 31, 2025 and the three-month period ended March 31, 2026 and subsequent events - Subsequent events (Details) Details http://www.abivax.com/role/SignificanteventsfortheyearendedDecember312025andthethreemonthperiodendedMarch312026andsubsequentevents 53 false false R54.htm 9955531 - Disclosure - Segment information (Details) Sheet http://www.abivax.com/role/SegmentinformationDetails Segment information (Details) Details http://www.abivax.com/role/Segmentinformation 54 false false R55.htm 9955532 - Disclosure - Goodwill and impairment test (Details) Sheet http://www.abivax.com/role/GoodwillandimpairmenttestDetails Goodwill and impairment test (Details) Details http://www.abivax.com/role/Goodwillandimpairmenttest 55 false false R56.htm 9955533 - Disclosure - Intangible assets - Narrative (Details) Sheet http://www.abivax.com/role/IntangibleassetsNarrativeDetails Intangible assets - Narrative (Details) Details 56 false false R57.htm 9955534 - Disclosure - Intangible assets - Disclosure of reconciliation of intangible assets (Details) Sheet http://www.abivax.com/role/IntangibleassetsDisclosureofreconciliationofintangibleassetsDetails Intangible assets - Disclosure of reconciliation of intangible assets (Details) Details 57 false false R58.htm 9955535 - Disclosure - Property, plant and equipment - Disclosure of reconciliation of property, plant and equipment (Details) Sheet http://www.abivax.com/role/PropertyplantandequipmentDisclosureofreconciliationofpropertyplantandequipmentDetails Property, plant and equipment - Disclosure of reconciliation of property, plant and equipment (Details) Details 58 false false R59.htm 9955536 - Disclosure - Property, plant and equipment - Narrative (Details) Sheet http://www.abivax.com/role/PropertyplantandequipmentNarrativeDetails Property, plant and equipment - Narrative (Details) Details 59 false false R60.htm 9955537 - Disclosure - Other financial assets - Disclosure of other financial assets (Details) Sheet http://www.abivax.com/role/OtherfinancialassetsDisclosureofotherfinancialassetsDetails Other financial assets - Disclosure of other financial assets (Details) Details 60 false false R61.htm 9955538 - Disclosure - Other financial assets - Narrative (Details) Sheet http://www.abivax.com/role/OtherfinancialassetsNarrativeDetails Other financial assets - Narrative (Details) Details 61 false false R62.htm 9955539 - Disclosure - Other receivables and assets - Disclosure of other receivables and other assets (Details) Sheet http://www.abivax.com/role/OtherreceivablesandassetsDisclosureofotherreceivablesandotherassetsDetails Other receivables and assets - Disclosure of other receivables and other assets (Details) Details 62 false false R63.htm 9955540 - Disclosure - Other receivables and assets - Narrative (Details) Sheet http://www.abivax.com/role/OtherreceivablesandassetsNarrativeDetails Other receivables and assets - Narrative (Details) Details 63 false false R64.htm 9955541 - Disclosure - Cash and cash equivalents - Disclosure of composition of cash and cash equivalents (Details) Sheet http://www.abivax.com/role/CashandcashequivalentsDisclosureofcompositionofcashandcashequivalentsDetails Cash and cash equivalents - Disclosure of composition of cash and cash equivalents (Details) Details 64 false false R65.htm 9955542 - Disclosure - Cash and cash equivalents - Narrative (Details) Sheet http://www.abivax.com/role/CashandcashequivalentsNarrativeDetails Cash and cash equivalents - Narrative (Details) Details 65 false false R66.htm 9955543 - Disclosure - Financial assets and liabilities (Details) Sheet http://www.abivax.com/role/FinancialassetsandliabilitiesDetails Financial assets and liabilities (Details) Details http://www.abivax.com/role/FinancialassetsandliabilitiesTables 66 false false R67.htm 9955544 - Disclosure - Shareholders’ equity - Share capital issued (Details) Sheet http://www.abivax.com/role/ShareholdersequitySharecapitalissuedDetails Shareholders’ equity - Share capital issued (Details) Details 67 false false R68.htm 9955545 - Disclosure - Shareholders’ equity - Change in share capital (Details) Sheet http://www.abivax.com/role/ShareholdersequityChangeinsharecapitalDetails Shareholders’ equity - Change in share capital (Details) Details 68 false false R69.htm 9955546 - Disclosure - Share-based payments - Disclosure of reconciliation of BCEs (Details) Sheet http://www.abivax.com/role/SharebasedpaymentsDisclosureofreconciliationofBCEsDetails Share-based payments - Disclosure of reconciliation of BCEs (Details) Details 69 false false R70.htm 9955547 - Disclosure - Share-based payments - Disclosure of reconciliation of BSAs (Details) Sheet http://www.abivax.com/role/SharebasedpaymentsDisclosureofreconciliationofBSAsDetails Share-based payments - Disclosure of reconciliation of BSAs (Details) Details 70 false false R71.htm 9955548 - Disclosure - Share-based payments - Narrative (Details) Sheet http://www.abivax.com/role/SharebasedpaymentsNarrativeDetails Share-based payments - Narrative (Details) Details 71 false false R72.htm 9955549 - Disclosure - Share-based payments - Disclosure of fair value of the BSAs at grant date using the Black Scholes model (Details) Sheet http://www.abivax.com/role/SharebasedpaymentsDisclosureoffairvalueoftheBSAsatgrantdateusingtheBlackScholesmodelDetails Share-based payments - Disclosure of fair value of the BSAs at grant date using the Black Scholes model (Details) Details 72 false false R73.htm 9955550 - Disclosure - Share-based payments - Disclosure of reconciliation of AGAs (Details) Sheet http://www.abivax.com/role/SharebasedpaymentsDisclosureofreconciliationofAGAsDetails Share-based payments - Disclosure of reconciliation of AGAs (Details) Details 73 false false R74.htm 9955551 - Disclosure - Share-based payments - Disclosure of assumptions used for the measurement of AGAs (Details) Sheet http://www.abivax.com/role/SharebasedpaymentsDisclosureofassumptionsusedforthemeasurementofAGAsDetails Share-based payments - Disclosure of assumptions used for the measurement of AGAs (Details) Details 74 false false R75.htm 9955552 - Disclosure - Share-based payments - Disclosure of breakdown of the compensation expenses (Details) Sheet http://www.abivax.com/role/SharebasedpaymentsDisclosureofbreakdownofthecompensationexpensesDetails Share-based payments - Disclosure of breakdown of the compensation expenses (Details) Details 75 false false R76.htm 9955553 - Disclosure - Financial liabilities - Disclosure of financial liabilities breakdown (Details) Sheet http://www.abivax.com/role/FinancialliabilitiesDisclosureoffinancialliabilitiesbreakdownDetails Financial liabilities - Disclosure of financial liabilities breakdown (Details) Details 76 false false R77.htm 9955554 - Disclosure - Financial liabilities - Kreos / Claret Financing (Details) Sheet http://www.abivax.com/role/FinancialliabilitiesKreosClaretFinancingDetails Financial liabilities - Kreos / Claret Financing (Details) Details 77 false false R78.htm 9955555 - Disclosure - Financial liabilities - Heights convertible notes (Details) Notes http://www.abivax.com/role/FinancialliabilitiesHeightsconvertiblenotesDetails Financial liabilities - Heights convertible notes (Details) Details 78 false false R79.htm 9955556 - Disclosure - Financial liabilities - Disclosure of variation in lease liabilities (Details) Sheet http://www.abivax.com/role/FinancialliabilitiesDisclosureofvariationinleaseliabilitiesDetails Financial liabilities - Disclosure of variation in lease liabilities (Details) Details 79 false false R80.htm 9955557 - Disclosure - Financial liabilities - Lease liabilities (Details) Sheet http://www.abivax.com/role/FinancialliabilitiesLeaseliabilitiesDetails Financial liabilities - Lease liabilities (Details) Details 80 false false R81.htm 9955558 - Disclosure - Financial liabilities - Royalty certificates (Details) Sheet http://www.abivax.com/role/FinancialliabilitiesRoyaltycertificatesDetails Financial liabilities - Royalty certificates (Details) Details 81 false false R82.htm 9955559 - Disclosure - Financial liabilities - Disclosure of reconciliation of liabilities arising from financing activities (Details) Sheet http://www.abivax.com/role/FinancialliabilitiesDisclosureofreconciliationofliabilitiesarisingfromfinancingactivitiesDetails Financial liabilities - Disclosure of reconciliation of liabilities arising from financing activities (Details) Details 82 false false R83.htm 9955560 - Disclosure - Financial liabilities - Disclosure of changes in derivative instruments (Details) Sheet http://www.abivax.com/role/FinancialliabilitiesDisclosureofchangesinderivativeinstrumentsDetails Financial liabilities - Disclosure of changes in derivative instruments (Details) Details 83 false false R84.htm 9955561 - Disclosure - Financial liabilities - Disclosure of remaining contractual maturities of financial liabilities (Details) Sheet http://www.abivax.com/role/FinancialliabilitiesDisclosureofremainingcontractualmaturitiesoffinancialliabilitiesDetails Financial liabilities - Disclosure of remaining contractual maturities of financial liabilities (Details) Details 84 false false R85.htm 9955562 - Disclosure - Payables, other current liabilities and provisions - Disclosure of breakdown of trade and other payables (Details) Sheet http://www.abivax.com/role/PayablesothercurrentliabilitiesandprovisionsDisclosureofbreakdownoftradeandotherpayablesDetails Payables, other current liabilities and provisions - Disclosure of breakdown of trade and other payables (Details) Details 85 false false R86.htm 9955563 - Disclosure - Payables, other current liabilities and provisions - Disclosure of tax and employee-related payables (Details) Sheet http://www.abivax.com/role/PayablesothercurrentliabilitiesandprovisionsDisclosureoftaxandemployeerelatedpayablesDetails Payables, other current liabilities and provisions - Disclosure of tax and employee-related payables (Details) Details 86 false false R87.htm 9955564 - Disclosure - Payables, other current liabilities and provisions (Details) Sheet http://www.abivax.com/role/PayablesothercurrentliabilitiesandprovisionsDetails Payables, other current liabilities and provisions (Details) Details http://www.abivax.com/role/PayablesothercurrentliabilitiesandprovisionsTables 87 false false R88.htm 9955565 - Disclosure - Operating income - Disclosure of breakdown of operating income (Details) Sheet http://www.abivax.com/role/OperatingincomeDisclosureofbreakdownofoperatingincomeDetails Operating income - Disclosure of breakdown of operating income (Details) Details 88 false false R89.htm 9955566 - Disclosure - Operating income - Narrative (Details) Sheet http://www.abivax.com/role/OperatingincomeNarrativeDetails Operating income - Narrative (Details) Details 89 false false R90.htm 9955567 - Disclosure - Operating expenses - Disclosure of sales and marketing expenses (Details) Sheet http://www.abivax.com/role/OperatingexpensesDisclosureofsalesandmarketingexpensesDetails Operating expenses - Disclosure of sales and marketing expenses (Details) Details 90 false false R91.htm 9955568 - Disclosure - Operating expenses - Narrative (Details) Sheet http://www.abivax.com/role/OperatingexpensesNarrativeDetails Operating expenses - Narrative (Details) Details 91 false false R92.htm 9955569 - Disclosure - Operating expenses - Disclosure of research and development expenses (Details) Sheet http://www.abivax.com/role/OperatingexpensesDisclosureofresearchanddevelopmentexpensesDetails Operating expenses - Disclosure of research and development expenses (Details) Details 92 false false R93.htm 9955570 - Disclosure - Operating expenses - Disclosure of general and administrative expenses (Details) Sheet http://www.abivax.com/role/OperatingexpensesDisclosureofgeneralandadministrativeexpensesDetails Operating expenses - Disclosure of general and administrative expenses (Details) Details 93 false false R94.htm 9955571 - Disclosure - Employees (Details) Sheet http://www.abivax.com/role/EmployeesDetails Employees (Details) Details http://www.abivax.com/role/EmployeesTables 94 false false R95.htm 9955572 - Disclosure - Financial gain (loss) - Disclosure of net financial income (loss) (Details) Sheet http://www.abivax.com/role/FinancialgainlossDisclosureofnetfinancialincomelossDetails Financial gain (loss) - Disclosure of net financial income (loss) (Details) Details http://www.abivax.com/role/FinancialgainlossTables 95 false false R96.htm 9955573 - Disclosure - Financial gain (loss) - Narrative (Details) Sheet http://www.abivax.com/role/FinancialgainlossNarrativeDetails Financial gain (loss) - Narrative (Details) Details http://www.abivax.com/role/FinancialgainlossTables 96 false false R97.htm 9955574 - Disclosure - Income taxes (Details) Sheet http://www.abivax.com/role/IncometaxesDetails Income taxes (Details) Details http://www.abivax.com/role/Incometax 97 false false R98.htm 9955575 - Disclosure - Loss per share (Details) Sheet http://www.abivax.com/role/LosspershareDetails Loss per share (Details) Details http://www.abivax.com/role/LosspershareTables 98 false false R99.htm 9955576 - Disclosure - Off-balance sheet commitments given and contingent liabilities (Details) Sheet http://www.abivax.com/role/OffbalancesheetcommitmentsgivenandcontingentliabilitiesDetails Off-balance sheet commitments given and contingent liabilities (Details) Details http://www.abivax.com/role/Offbalancesheetcommitmentsgivenandcontingentliabilities 99 false false R100.htm 9955577 - Disclosure - Management and assessment of financial risks (Details) Sheet http://www.abivax.com/role/ManagementandassessmentoffinancialrisksDetails Management and assessment of financial risks (Details) Details http://www.abivax.com/role/Managementandassessmentoffinancialrisks 100 false false All Reports Book All Reports abvx-20260331.htm abvx-20260331.xsd abvx-20260331_cal.xml abvx-20260331_def.xml abvx-20260331_lab.xml abvx-20260331_pre.xml http://xbrl.sec.gov/dei/2025 https://xbrl.ifrs.org/taxonomy/2025-03-27/ifrs-full true true