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Collaboration Agreement with GSK - Additional Information (Details) $ in Thousands |  |  | 1 Months Ended | 3 Months Ended |
--- | --- | --- | --- | --- | ---
Aug. 17, 2021 USD ($) | Jul. 01, 2021 USD ($) | May 31, 2023 USD ($) | Jan. 31, 2022 USD ($) | Mar. 31, 2026 USD ($) | Mar. 31, 2025 USD ($) | Dec. 31, 2025 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |
Research and development expense |  |  |  |  | $ 17,857 | $ 33,641 |
GlaxoSmithKline plc |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |
Effective date of agreement | Aug. 17, 2021 |  |  |  |  |  |
Upfront payments |  | $ 700,000 |  |  | $ 700,000 |  |
Milestone payment received | $ 500,000 |  |  | $ 200,000 |  |  |
Percentage Of Development Cost |  |  |  |  | 0.60 |  |
Collaboration revenue |  |  |  |  | $ 1,000 | 3,700 |
Deferred revenue |  |  |  |  | 169,600 |  | $ 171,200
Research and development expense |  |  |  |  | 1,800 | $ 4,300 |
Transaction price |  |  |  |  | 568,000 |  |
Contract with customer, refund liability |  |  |  |  | 0 |  | $ 11,400
Maximum funding |  |  | $ 140,500 |  |  |  |
GlaxoSmithKline plc | Maximum |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |
Additional milestone payments related to initiation of certain clinical studies and regulatory approval |  |  |  |  | $ 1,500,000 |  |
Alector |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |
Percentage Of Development Cost |  |  |  |  | 0.40 |  |

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