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v3.25.3

Segment Information - Schedule of Reconciliation of Significant Segment Expenses (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Jun. 30, 2025 | Mar. 31, 2025 | Sep. 30, 2024 | Jun. 30, 2024 | Mar. 31, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |
Total external R&D program expenses |  | $ (4,785) |  |  | $ 17,313 |  |  | $ 30,234 | $ 49,838
Total internal R&D expenses |  | 497 |  |  | 10,272 |  |  | 16,180 | 32,159
Total R&D expenses |  | (4,288) |  |  | 27,585 |  |  | 46,414 | 81,997
Total G & A expenses |  | 8,254 |  |  | 6,513 |  |  | 23,292 | 20,411
Total restructuring expenses |  |  |  |  |  |  |  | 17,486 |
Other segment (income) expense | [1] | (260) |  |  | (2,339) |  |  | (2,367) | (8,168)
Segment net loss |  | 3,706 | $ 47,982 | $ 33,137 | 31,759 | $ 31,564 | $ 30,917 | 84,825 | 94,240
ARTISTRY-6 |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |
Total external R&D program expenses |  | (4,802) |  |  | 3,075 |  |  | 3,898 | 6,907
ARTISTRY-7 |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |
Total external R&D program expenses |  | (71) |  |  | 4,801 |  |  | 4,778 | 15,591
Early Discovery Programs |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |
Total external R&D program expenses |  | 11 |  |  | 700 |  |  | 5,341 | 2,142
Employee-Related |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |
Total internal R&D expenses |  | 493 |  |  | 7,635 |  |  | 12,386 | 24,143
Total G & A expenses |  | 980 |  |  | 3,443 |  |  | 6,823 | 11,170
Total restructuring expenses |  |  |  |  |  |  |  | 9,457 |
Other External R&D Program Expenses |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |
Total external R&D program expenses | [2] | 77 |  |  | 8,737 |  |  | 16,217 | 25,198
Other Internal R&D Expenses |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |
Total internal R&D expenses | [3] | 4 |  |  | 2,637 |  |  | 3,794 | 8,016
Other G&A expenses |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |
Total G & A expenses | [4] | $ 7,274 |  |  | $ 3,070 |  |  | 16,469 | $ 9,241
Other restructuring expenses |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |
Total restructuring expenses | [5] |  |  |  |  |  |  | $ 8,029 |
[1] | Other non-operating (income) expense included in segment net loss includes interest income, tax expense, and other non-operating income and expense. During the three months ended September 30, 2025, the Company and one of its CROs completed the review and reconciliation of the costs incurred during the ARTISTRY-6 trial following the close-out of all clinical trial sites, concluding that actual costs incurred were approximately $4.8 million less than estimated over the course of the trial. The reduction in the estimated costs incurred during the ARTISTRY-6 trial was recorded as a change in estimate during the three months ended September 30, 2025 as a credit to R&D expense.
[2] | Other external R&D program expenses included in segment net loss include expenses related to other clinical trials and general external program expenses.
[3] | Other internal R&D expenses included in segment net loss include expenses related to occupancy and depreciation.
[4] | Other G&A expenses included in segment net loss include expenses related to professional fees, information technology, depreciation, and other general G&A expenses.
[5] | Other restructuring expenses include contract termination costs, impairment and asset write-offs incurred in connection with our reduction-in-force and the termination of certain development programs.

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