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Liability Related to Sale of Future Revenues - Additional Information (Detail) - USD ($) | 1 Months Ended | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Nov. 30, 2022 | Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Total revenue |  | $ 1,076,000 | $ 123,000 | $ 5,163,000 | $ 26,486,000
Interest expense related to sale of future revenues |  |  |  | 6,109,000 |
Interest paid |  |  |  | $ 450,000 | 5,700,000
NovaQuest Capital Management [Member] | Revenue Interest Financing Agreement [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Effective annual interest rate related to sale of future revenues |  |  |  | 15.23% |
NovaQuest Capital Management [Member] | Revenue Interest Financing Agreement [Member] | Minimum [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Prepayment amount of 2024 to 2030 | $ 80,000,000 |  |  |  |
NovaQuest Capital Management [Member] | Revenue Interest Financing Agreement [Member] | Maximum [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Prepayment amount of 2024 to 2030 | 125,000,000 |  |  |  |
NovaQuest Capital Management [Member] | Payment Period One [Member] | Revenue Interest Financing Agreement [Member] | Minimum [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Revenue interest payment | 62,500,000 |  |  |  |
NovaQuest Capital Management [Member] | Payment Cap Date on or before December 31, 2028 [Member] | Revenue Interest Financing Agreement [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Maximum payment cap amount | 100,000,000 |  |  |  |
NovaQuest Capital Management [Member] | Payment Cap Date on or after January 1, 2029 [Member] | Revenue Interest Financing Agreement [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Maximum payment cap amount | 112,500,000 |  |  |  |
NovaQuest Capital Management [Member] | Payment Cap Date after January 1, 2030 [Member] | Revenue Interest Financing Agreement [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Maximum payment cap amount | 125,000,000 |  |  |  |
NovaQuest Capital Management [Member] | Payment Period Two [Member] | Revenue Interest Financing Agreement [Member] | Minimum [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Revenue interest payment | 125,000,000 |  |  |  |
Product [Member] | NovaQuest Capital Management [Member] | Revenue Interest Financing Agreement [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Revenue interest payment | 10,000,000 |  |  |  |
Other Revenue - Contract Manufacturing [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Total revenue |  | 119,000 | 385,000 | $ 396,000 | 1,532,000
Astellas Agreement [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Future revenue granted | $ 50,000,000 |  |  |  |
Percentage of revenue interest on global net sales | 100.00% |  |  |  |
Astellas Agreement [Member] | Maximum [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Revenue payment cap amount |  | 125,000,000 |  | 125,000,000 |
Astellas Agreement [Member] | Product [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Percentage of revenue sold | 22.50% |  |  |  |
Astellas Agreement [Member] | Milestone payments [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Percentage of revenue sold | 10.00% |  |  |  |
Astellas Agreement [Member] | Milestone payments [Member] | Payment Period One [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Percentage of revenue sold | 20.00% |  |  |  |
Development Revenue [Member] | Astellas Agreement [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Total revenue |  | 100,000 | 400,000 | 400,000 | 1,000,000
Drug Product Revenue [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Total revenue |  | 957,000 | (262,000) | 4,767,000 | 24,954,000
Drug Product Revenue [Member] | Astellas Agreement [Member] |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |
Total revenue |  | 1,000,000 | (300,000) | 4,800,000 | (700,000)
Non-cash interest expense related to drug product revenue |  | $ 2,000,000 | $ 2,000,000 | $ 6,100,000 | $ 5,800,000

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