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Collaborative Arrangements - Daiicho Sankyo - Narrative (Details) $ in Millions | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Aug. 31, 2024 USD ($) | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Dec. 31, 2023 USD ($) candidate
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |
Research and development |  | $ 4,234 | $ 5,862 | $ 11,903 | $ 13,354 |
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |
Number of antibody drug conjugates obtained right and obligations | candidate |  |  |  |  |  | 3
Aggregate upfront payments due upon execution in collaborative arrangement |  |  |  |  |  | $ 4,000
Refundable upfront payments in collaborative arrangement |  |  |  |  |  | 1,000
Maximum aggregate contingent milestone payments, per product, in collaborative arrangement |  |  |  |  |  | 5,500
Research and development |  | $ 110 | $ 94 | $ 379 | $ 227 | $ 5,500
Sales based royalty percentage | 5.00% |  |  |  |  | 5.00%
Upfront cash payment | $ 170 |  |  |  |  |
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Ifinatamab Deruxtecan |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |
Refundable upfront payments in collaborative arrangement |  |  |  |  |  | $ 500
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Patritumab Deruxtecan |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |
Refundable upfront payments in collaborative arrangement |  |  |  |  |  | 500
Aggregate upfront payments due upon lapse of time in collaborative arrangement |  |  |  |  |  | 750
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Raludotatug Deruxtecan |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |
Aggregate upfront payments due upon lapse of time in collaborative arrangement |  |  |  |  |  | $ 750
Liable contracted portion of research and development expenses to incur costs for in collaborative arrangement, percentage |  |  |  |  |  | 75.00%
Liable contracted portion of research and development expenses to incur costs for in collaborative arrangement |  |  |  |  |  | $ 2,000
Daiichi Sankyo | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Patritumab Deruxtecan and Ralduotatug Deruxtecan |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |
Aggregate upfront payments due upon lapse of time in collaborative arrangement |  |  |  |  |  | $ 1,500

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