v3.25.1

Summary of significant transactions - Evolution of the total transaction price (Details) - EUR (€) | Dec. 31, 2024 | Jan. 31, 2024 | Dec. 31, 2023 | Jun. 30, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2015
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Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Purchase Commitment Related To Services From Novalix. | € 41,600,000 |  |  |  |  |  |  |  |
Gilead |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Upfront consideration | 4,018,016,000 |  | € 4,018,016,000 |  | € 4,018,016,000 |  |  |  |
Milestones achieved, balance | 212,601,000 |  | 212,601,000 |  | 212,601,000 |  |  |  |
Royalties, balance | 50,780,000 |  | 40,176,000 |  | 30,710,000 |  |  |  |
Impact initial valuation of share subscription | 124,604,000 |  | 124,604,000 |  | 124,604,000 |  |  |  |
Transaction price before warrants issuances liabilities | 4,406,001,000 |  | 4,395,397,000 |  | 4,385,931,000 |  |  |  |
Allocation to performance obligations | 4,360,136,000 |  | 4,349,487,000 |  | 4,339,347,000 |  |  |  |
Gilead | Other movements in 2023 |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Royalties Amount Received |  |  | 9,466,000 |  |  |  |  |  |
Transaction price before warrants issuances liabilities |  |  | 9,466,000 |  |  |  |  |  |
Allocation to performance obligations |  |  | 10,140,000 |  |  |  |  |  |
Gilead | Other Movements In 2024 Member |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Royalties Amount Received | 10,604,000 |  |  |  |  |  |  |  |
Transaction price before warrants issuances liabilities | 10,604,000 |  |  |  |  |  |  |  |
Allocation to performance obligations | 10,649,000 |  |  |  |  |  |  |  |
Warrant A | Gilead |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Less : Warrants issuance liabilities | (43,311,000) |  | (43,311,000) |  | (43,311,000) |  |  |  |
Initial Warrant B | Gilead |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Less : Warrants issuance liabilities | (2,545,000) |  | (2,545,000) |  | (2,545,000) |  |  |  |
Subsequent warrant B | Gilead |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Less : Warrants issuance liabilities | (9,000) |  | (54,000) |  | (728,000) |  |  |  |
Subsequent warrant B | Gilead | Other movements in 2023 |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Less : Warrants issuance liabilities |  |  | 674,000 |  |  |  |  |  |
Subsequent warrant B | Gilead | Other Movements In 2024 Member |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Less : Warrants issuance liabilities | 45,000 |  |  |  |  |  |  |  |
Filgotinib Performance Obligation Member | Gilead |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Upfront consideration |  |  |  |  |  |  | € 160,000,000 |  | € 275,600,000
Allocation to performance obligations | 1,392,248,000 |  | 1,381,644,000 |  | 1,372,178,000 |  |  |  |
Estimated significant financing component |  | € 39,300,000 | 39,800,000 |  | 58,700,000 |  |  | € 44,500,000 |
Filgotinib Performance Obligation Member | Gilead | Original Agreement |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Upfront consideration |  |  | 4,000,000,000 |  |  |  |  |  |
Filgotinib Performance Obligation Member | Gilead | First Revised Agreement |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Upfront consideration |  |  |  |  |  |  |  | € 3,600,000,000 |
Filgotinib Performance Obligation Member | Gilead | Second Revised Agreement |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Upfront consideration |  |  |  |  |  |  | € 172,600,000 |  |
Filgotinib Performance Obligation Member | Gilead | Amendments Relating To The Diversity Study [member] |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Upfront consideration |  |  |  |  |  | € 12,600,000 |  |  |
Filgotinib Performance Obligation Member | Gilead | Other movements in 2023 |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Allocation to performance obligations |  |  | 9,466,000 |  |  |  |  |  |
Filgotinib Performance Obligation Member | Gilead | Other Movements In 2024 Member |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Allocation to performance obligations | 10,604,000 |  |  |  |  |  |  |  |
Gilead collaboration agreement for ziritaxestat | Gilead |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Allocation to performance obligations | 666,967,000 |  | 666,967,000 |  | 666,967,000 |  |  |  |
Collaboration agreement for drug discovery platform | Gilead |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Allocation to performance obligations | 2,300,921,000 |  | 2,300,876,000 |  | € 2,300,203,000 |  |  |  |
Collaboration agreement for drug discovery platform | Gilead | Other movements in 2023 |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Allocation to performance obligations |  |  | € 674,000 |  |  |  |  |  |
Collaboration agreement for drug discovery platform | Gilead | Other Movements In 2024 Member |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Allocation to performance obligations | € 45,000 |  |  |  |  |  |  |  |
Drug discovery collaboration transaction with NovAliX |  |  |  |  |  |  |  |  |
Summary Of Significant Transaction [line items] |  |  |  |  |  |  |  |  |
Collaboration Agreement Upfront Payment |  |  |  | € 8,300,000 |  |  |  |  |

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