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License and Collaboration Agreements - Additional Information (Details) - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended | 6 Months Ended
--- | --- | --- | ---
Jun. 30, 2025 | Jun. 30, 2026 | Jun. 30, 2025 | Jun. 30, 2026 | Jun. 30, 2025
License And Collaboration Agreements [Line Items] |  |  |  |  |
Research and development costs |  | $ 44,437 | $ 61,030 | $ 86,560 | $ 102,489
General and administrative Cost |  | 12,817 | 14,768 | $ 24,391 | 28,305
Genrix License Agreement | Research and Development |  |  |  |  |
License And Collaboration Agreements [Line Items] |  |  |  |  |
Upfront license fee | $ 20,000 |  |  |  |
Pearl - Taiho |  |  |  |  |
License And Collaboration Agreements [Line Items] |  |  |  |  |
Percentage of profits from potential sales |  |  |  | 50.00% |
Percentage of Independent Development Costs |  |  |  | 50.00% |
RecievablesFromRelatedParty |  | 130,000 |  | $ 130,000 |
Pearl - Taiho | Collaboration Agreements |  |  |  |  |
License And Collaboration Agreements [Line Items] |  |  |  |  |
Research and development costs |  | 652 | 3,112 | 1,474 | 4,486
Genrix Biopharmaceutical Co, Ltd | Genrix License Agreement |  |  |  |  |
License And Collaboration Agreements [Line Items] |  |  |  |  |
Upfront license fee |  |  |  | 20,000 |
Genrix Biopharmaceutical Co, Ltd | Maximum | Genrix License Agreement |  |  |  |  |
License And Collaboration Agreements [Line Items] |  |  |  |  |
Milestone payments |  |  |  | 292,000 |
Genrix Biopharmaceutical Co, Ltd | Maximum | Genrix License Agreement | Sales Based [Member] |  |  |  |  |
License And Collaboration Agreements [Line Items] |  |  |  |  |
Milestone payments |  |  |  | 400,000 |
Cullinan [Member] | Collaboration Agreements |  |  |  |  |
License And Collaboration Agreements [Line Items] |  |  |  |  |
Research and development costs |  | 6,618 | 7,772 | 12,428 | 13,390
General and administrative Cost |  | $ 1,005 | $ 592 | $ 1,671 | $ 1,064

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