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Segment Reporting - Segment Profit And Loss (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023
Segment Reporting |  |
Research and development | $ 77,106 | $ 42,127
General and administrative | 34,452 | 25,704
Stock-based compensation expense | 13,042 | 6,314
Acquired in-process research and development |  | 15,199
Other income, net | 17,298 | 10,139
Net Loss | (94,260) | (72,891)
Single reportable segment |  |
Segment Reporting |  |
Stock-based compensation expense | 12,907 | 6,313
Consulting and professional services expenses | 17,952 | 9,382
Other segment expenses | 5,790 | 7,810
Acquired in-process research and development |  | 15,199
Other income, net | (17,298) | (10,139)
Net Loss | 94,260 | 72,891
Single reportable segment | Navenibart |  |
Segment Reporting |  |
Research and development | 32,401 | 24,186
Single reportable segment | STAR-0310 |  |
Segment Reporting |  |
Research and development | 15,497 | 677
Single reportable segment | Employee expenses |  |
Segment Reporting |  |
Research and development | 14,415 | 9,859
General and administrative | 11,575 | 9,128
Single reportable segment | Program support |  |
Segment Reporting |  |
General and administrative | $ 1,021 | $ 476

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