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Convertible preferred stock shares issued value.

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Extra milestone payment.

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Issuance of convertible preferred stock shares.

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Milestone and royalties incurred.

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Other milestone and royalties incurred.

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Payments on outstanding liability.

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Research and development licensed product estimated cost.

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Upfront payments.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Amount of addition (reduction) to the amount at which a liability could be incurred (settled) in a current transaction between willing parties.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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License Agreements - Additional Information (Details) - USD ($)	1 Months Ended				3 Months Ended		9 Months Ended
	Apr. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Apr. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jan. 31, 2021
Research And Development Arrangement Contract To Perform For Others [Line Items]
Research and development expense					$ 7,849,000	$ 2,425,000	$ 43,828,000	$ 5,909,000
Proceeds from stock options exercised							14,000	31,000
Pfizer License Agreement
Research And Development Arrangement Contract To Perform For Others [Line Items]
Research and development expense					0		25,000,000.0
Milestone and royalties incurred					0		0
Upfront payments							$ 5,000,000.0
Pfizer License Agreement \| Series B Convertible Preferred Stock
Research And Development Arrangement Contract To Perform For Others [Line Items]
Issuance of convertible preferred stock shares							12,152,145
Issuance of convertible preferred stock value					20,000,000.0		$ 20,000,000.0
LegoChem License Agreement
Research And Development Arrangement Contract To Perform For Others [Line Items]
Research and development expense							9,000,000.0
Milestone and royalties incurred					0		0
Payments to purchase licensed products		$ 9,000,000.0	$ 500,000				9,000,000.0
Licensed product estimated cost			7,000,000.0
Accrued research and development expenses			$ 500,000
Settlement on outstanding liability		$ 500,000
Proceeds from stock options exercised	$ 8,000,000.0			$ 8,000,000.0
Extra milestone payment				$ 9,600,000
Derivative liability					9,200,000		9,200,000		$ 3,400,000
Fair value adjustment to the derivative liability					2,600,000		5,800,000
Other milestone and royalties incurred					0		0
LegoChem License Agreement \| Series B Convertible Preferred Stock
Research And Development Arrangement Contract To Perform For Others [Line Items]
Issuance of convertible preferred stock shares		303,804
University License Agreement
Research And Development Arrangement Contract To Perform For Others [Line Items]
Stock issued				311,076
Stock issued, shares, reverse stock splits				48,919
Research and development expense					0		0	$ 3,000
Milestone and royalties incurred					$ 0		$ 0