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Payment related to publication of US patent application.

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Sales milestone payments obligation.

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Upfront payment.

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License Agreements - Additional Information (Details) - USD ($)	1 Months Ended									3 Months Ended		12 Months Ended
	Dec. 31, 2022	Mar. 31, 2022	Aug. 31, 2021	May 31, 2021	Jan. 31, 2021	Apr. 30, 2020	Mar. 31, 2020	Feb. 29, 2020	Dec. 31, 2018	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
License Agreements [Line Items]
In-process research and development											$ 2,000,000
Accounts payable	$ 23,049,000									$ 3,353,000		$ 23,049,000
License Agreement \| Novartis Pharma AG
License Agreements [Line Items]
Upfront payment	20,000,000.0
In-process research and development												100,000,000.0
Accounts payable	20,000,000.0									0		20,000,000.0
Accrued milestone payment as underlying contingencies	0									0		0
Stock issued, value	$ 80,000,000.0
Stock issued and sold	12,307,692
License Agreement \| Novartis Pharma AG \| Maximum
License Agreements [Line Items]
Development and regulatory milestone payments obligation	$ 80,000,000.0
Sales milestone payments obligation	200,000,000.0
License Agreement \| NiKang Therapeutics, Inc.
License Agreements [Line Items]
Upfront payment								$ 5,000,000.0
Reimbursement of certain initial manufacturing costs								400,000
Payment for US patent application						$ 7,000,000.0
In-process research and development										0	0
Accrued milestone payment as underlying contingencies	0									0		0
License Agreement \| NiKang Therapeutics, Inc. \| First Licensed Product
License Agreements [Line Items]
Payment of development and regulatory milestone obligation					$ 4,000,000.0
License Agreement \| NiKang Therapeutics, Inc. \| First Licensed Product \| Maximum
License Agreements [Line Items]
Development and regulatory milestone payments obligation								16,000,000.0
Commercial milestone payments obligation								157,000,000.0
License Agreement \| NiKang Therapeutics, Inc. \| Second Licensed Product
License Agreements [Line Items]
Development and regulatory milestone payments obligation								12,000,000.0
Commercial milestone payments obligation								$ 151,000,000.0
License Agreement \| Katmai Pharmaceuticals, Inc.
License Agreements [Line Items]
Upfront payment							$ 5,700,000
Payment of development and regulatory milestone obligation		$ 2,000,000.0
In-process research and development										0	2,000,000.0
Accrued milestone payment as underlying contingencies	0									0		0
License Agreement \| Katmai Pharmaceuticals, Inc. \| Series B-1 Convertible Preferred Stock and Series B-2 Convertible Preferred Stock
License Agreements [Line Items]
Stock issued, value							$ 2,700,000
License Agreement \| Katmai Pharmaceuticals, Inc. \| Series B-1 Convertible Preferred Stock and Series B-2 Convertible Preferred Stock \| IPO
License Agreements [Line Items]
Conversion of convertible preferred stock into common stock							395,555
License Agreement \| Katmai Pharmaceuticals, Inc. \| Series B-1 Convertible Preferred Stock
License Agreements [Line Items]
Stock issued, value						$ 1,800,000
Stock issued and sold						356,000
License Agreement \| Katmai Pharmaceuticals, Inc. \| Series B-2 Convertible Preferred Stock
License Agreements [Line Items]
Stock issued, value					$ 900,000
Stock issued and sold					118,666
License Agreement \| Katmai Pharmaceuticals, Inc. \| Maximum
License Agreements [Line Items]
Development and regulatory milestone payments obligation							$ 26,000,000.0
Commercial milestone payments obligation							$ 101,000,000.0
License Agreement \| LifeArc
License Agreements [Line Items]
Upfront payment						$ 0
In-process research and development										0	0
Accrued milestone payment as underlying contingencies	0									0		0
One-time license payment						75,000
License Agreement \| LifeArc \| Maximum
License Agreements [Line Items]
Development and regulatory milestone payments obligation						11,000,000.0
Sales milestone payments obligation						$ 50,000,000.0
License Agreement \| The Regents
License Agreements [Line Items]
Upfront payment									$ 50,000
In-process research and development										0	$ 0
Sales milestone payments obligation									$ 2,000,000.0
Percentage of third tier sublicensing fees									30.00%
Cash payments in license agreement upon achievement of corporate milestone			$ 1,700,000
Milestones accrued	$ 0									$ 0		$ 0
License Agreement \| The Regents \| Common Stock
License Agreements [Line Items]
Stock issued and sold				944,945
License Agreement \| The Regents \| Maximum
License Agreements [Line Items]
Development and regulatory milestone payments obligation									$ 6,400,000