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License Agreements - Additional Information (Details) - USD ($)		1 Months Ended							12 Months Ended
	Jul. 20, 2021	Aug. 31, 2021	Jul. 31, 2021	May 31, 2021	Jan. 31, 2021	Apr. 30, 2020	Mar. 31, 2020	Feb. 29, 2020	Dec. 31, 2021	Dec. 31, 2020
License Agreements [Line Items]
In-process research and development									$ 10,848,000	$ 71,745,000
Common Stock
License Agreements [Line Items]
Convertible preferred stock converted into shares of common stock									71,263,685
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
Accrued development milestone payment									$ 0	4,000,000.0
In-process research and development									0	16,000,000.0
Ownership percentage of equity or assets								50.00%
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
In-process research and development									0	5,700,000
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
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	75,000
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									7,200,000	$ 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
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
IPO
License Agreements [Line Items]
Stock issued, value									316,999,000
IPO | Common Stock
License Agreements [Line Items]
Stock issued, value									$ 2,000
Stock issued and sold	21,562,500								21,562,500
Convertible preferred stock converted into shares of common stock	71,263,685		71,263,685
IPO | License Agreement | Katmai Pharmaceuticals, Inc. | Series B-1 Convertible Preferred Stock and Series B-2 Convertible Preferred Stock
License Agreements [Line Items]
Conversion of convertible preferred stock into common stock							395,555

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