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v3.23.1

Collaborations - Additional Information (Detail) - USD ($) |  | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Oct. 22, 2020 | Mar. 31, 2023 | Mar. 31, 2022 | Sep. 30, 2022 | Dec. 31, 2022
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |
Related party revenue recognized |  |  | $ 1,925,000 |  |
Ultragenyx [Member] | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement [Member] |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |
Milestone payments upon achievement of regulatory milestone |  | $ 65,000,000 |  |  |
Percentage of option to fund of development cost |  | 30.00% |  |  |
Percentage of net income and net losses on net sales |  | 30.00% |  |  |
Agreement termination notice period |  | 90 days |  |  |
Issued and sold shares of common stock | 521,719 |  |  |  |
Common stock issued price per share | $ 76.6695 |  |  |  |
Proceeds from issuance of common stock, net of issuance costs | $ 40,000,000 |  |  |  |
Percentage of outstanding common stock | 14.45% | 2.70% |  |  |
Transaction price determined under ASC 606 |  | $ 22,513,000 |  |  |
Transaction price |  | 0 |  |  |
Related party revenue recognized |  | 0 | $ 1,925,000 |  | $ 0
Deferred revenue - related party |  | 0 |  |  | $ 0
Ultragenyx [Member] | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement [Member] | Maximum [Member] |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |
Milestone payments upon achievement of development milestone |  | 25,000,000 |  |  |
Milestone Payments upon achievement of net sales milestones |  | $ 165,000,000 |  |  |
Ultragenyx [Member] | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement [Member] | Minimum [Member] |  |  |  |  |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] |  |  |  |  |
Percentage of outstanding common stock |  |  |  | 10.00% |

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