Aggregate number of common shares reserved for future issuance.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Description of service or performance condition required to be met for earning right to award under share-based payment arrangement. Includes, but is not limited to, combination of market, performance or service condition.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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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Gross number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Percentage of vesting of award under share-based payment arrangement.

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Per share or per unit amount of equity securities issued.

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Share-based Compensation - Additional Information (Details) - $ / shares	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2018	Aug. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares, Issued	32,129,970	32,129,970	706,701		23,410,348
Vested Upon Initiation of Clinical Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares, Issued			530,027
Vesting period			4 years
Fair value of underlying shares			$ 0.96
2021 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares reserved for issuance	5,440,344	5,440,344
2021 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares reserved for issuance	291,324	291,324
Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rights			Restricted common shares issued to the founders were to vest 25% upon the one-year anniversary of the initiation of a clinical program through one of its controlled subsidiaries, and monthly thereafter over the next 36 months.
Restricted common shares granted	0
Restricted Shares \| Vested Upon Initiation of Clinical Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common shares granted			530,027
Restricted Shares \| Remaining Vesting Term
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares, Issued			188,454
Restricted common shares granted			188,454
Weighted average fair value of restricted common shares			$ 0.96
Restricted Shares \| Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted common shares granted		1,589,622
Weighted average fair value of restricted common shares		$ 3.65
Employee Stock Options \| 2021 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Fair value of underlying shares	$ 9.34
Employee Stock Options \| Employees And Directors [Member] \| 2021 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares granted	1,232,759
Employee Stock Options \| Non Employee Director [Member] \| 2021 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares granted	80,640
Fair value of underlying shares	$ 9.15
Employee Stock Options \| Executive Officer And Chief Medical Officer [Member] \| 2021 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares granted	640,000
Fair value of underlying shares	$ 9.47
Vesting percentage	25.00%
IPO [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Issued, Price Per Share				$ 13.00