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Revenue- Incyte Corporation (Details) | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended | 24 Months Ended | 93 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Aug. 31, 2024 USD ($) | Jun. 30, 2024 USD ($) | Jan. 31, 2022 USD ($) | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2017 USD ($) performanceObligation | Dec. 31, 2018 USD ($) | Sep. 30, 2025 USD ($) | Mar. 31, 2025 USD ($) | Sep. 30, 2023 USD ($) | Jul. 31, 2022 USD ($)
Collaboration And Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  | $ 72,839,000 | $ 110,708,000 | $ 108,273,000 | $ 130,609,000 |  |  |  |  |  |  |
Deferred revenue, current |  |  |  | 10,302,000 |  | 10,302,000 |  | $ 16,319,000 |  |  | $ 10,302,000 |  |  |
Deferred revenue, net of current portion |  |  |  | 55,840,000 |  | 55,840,000 |  | 55,503,000 |  |  | 55,840,000 |  |  |
Incyte Corporation | Incyte MGA012 Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaboration And Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Non-refundable upfront payment |  |  |  |  |  |  |  |  | $ 150,000,000 |  |  |  |  |
Potential commercial milestone payments under agreement |  |  |  |  |  |  |  |  | 330,000,000 |  |  |  |  |
Potential development and regulatory milestone payments under agreement |  |  |  |  |  |  |  |  | 210,000,000 |  |  |  |  |
Development and regulatory milestones recognized | $ 100,000,000 |  |  |  |  |  |  | 100,000,000 |  |  | 215,000,000 |  |  |
Collaborative agreement transaction price |  |  |  |  |  |  |  |  | $ 154,000,000 |  |  |  |  |
Variable consideration recognized |  |  |  |  |  |  |  |  |  | $ 4,000,000 |  |  |  |
Number of performance obligations | performanceObligation |  |  |  |  |  |  |  |  | 2 |  |  |  |  |
Gilead | Gilead First Research Program |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaboration And Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  | $ 3,300,000 |  | 0 | 400,000 | 11,000,000 | 2,400,000 |  |  |  |  |  |  |
Deferred revenue, current |  |  |  | 0 |  | 0 |  | 11,000,000 |  |  | 0 |  |  |
Revenue, remaining performance obligation, amount |  |  |  |  |  |  |  |  |  |  |  |  | $ 15,700,000 |
Minimum | Incyte Corporation | Incyte MGA012 Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaboration And Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potential proceeds from royalties (percent) |  |  |  |  |  |  |  |  | 15.00% |  |  |  |  |
Maximum | Incyte Corporation | Incyte MGA012 Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaboration And Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Potential proceeds from royalties (percent) |  |  |  |  |  |  |  |  | 24.00% |  |  |  |  |
Revenues From License Agreements | Incyte Corporation | Incyte MGA012 Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaboration And Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  | 3,300,000 | 100,000 | 5,100,000 | 300,000 |  | $ 150,000,000 |  |  |  |  |
Revenues From License Agreements | Incyte Corporation | Incyte Commercial Supply Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaboration And Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  | 1,000,000 | 500,000 | 1,700,000 | 1,400,000 |  |  |  |  |  |  |
RevenuesFromCMOAgreementsMember | Incyte Corporation |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaboration And Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Non-refundable upfront payment |  |  | $ 10,000,000 |  |  |  |  |  |  |  |  |  |  |
Annual Fixed Payments |  |  | 14,400,000 |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  | 10,500,000 | $ 3,800,000 | 28,400,000 | $ 8,100,000 |  |  |  |  |  |  |
Deferred revenue, current |  |  |  | 0 |  | 0 |  | $ 3,400,000 |  |  | 0 |  |  |
RevenuesFromCMOAmendmentAgreement | Incyte Corporation |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaboration And Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Annual Fixed Payments |  |  | $ 41,700,000 |  |  |  |  |  |  |  |  |  |  |
Additional Payments |  |  |  |  |  |  |  |  |  |  |  | $ 13,500,000 |  | $ 5,100,000
Manufacturing Services | Incyte Corporation |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaboration And Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Extension term |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 year
Revenue, remaining performance obligation, amount |  |  |  | $ 16,800,000 |  | $ 16,800,000 |  |  |  |  | $ 16,800,000 |  |  |
Manufacturing Services | Incyte Corporation | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-02-01 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaboration And Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue, remaining performance obligation, expected timing of satisfaction |  |  | 3 years |  |  |  |  |  |  |  |  |  |  |
Manufacturing Services | Incyte Corporation | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-10-01 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collaboration And Other Agreements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenue, remaining performance obligation, expected timing of satisfaction |  |  |  | 3 years |  | 3 years |  |  |  |  | 3 years |  |  |

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