Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
Dec. 31, 2021 USD ($) SupplyChain	Dec. 31, 2020 USD ($)
Significant Accounting Policies [Line Items]
Impairment of long-lived assets	$ 0
Accounts receivable, allowance for doubtful accounts	0	$ 0
Bad debt expense	0	$ 0
Inventory Write-down	0
Interest charged in relation to unrecognized tax benefits	0
Penalties charged in relation to unrecognized tax benefits	$ 0
Supplier Concentration Risk [Member]
Significant Accounting Policies [Line Items]
Concentration risk, supplier	The Company relies on one supply chain for each of its product candidates. If any of the single source suppliers in any of the supply chains fail to satisfy the Company’s requirements on a timely basis, it could suffer delays in its clinical development programs and activities, which could adversely affect its operating results.
Number of supply chains for each product candidate \| SupplyChain	1
Supplier Concentration Risk [Member] \| Revenue Member]
Significant Accounting Policies [Line Items]
Percentage Of Amount Accounted For Customer	94.00%
Supplier Concentration Risk [Member] \| Customer 1 \| Accounts Receivable [Member]
Significant Accounting Policies [Line Items]
Percentage Of Amount Accounted For Customer	66.00%
Supplier Concentration Risk [Member] \| Customer 2 \| Accounts Receivable [Member]
Significant Accounting Policies [Line Items]
Percentage Of Amount Accounted For Customer	34.00%

Number of supply chains for each product candidate.

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Significant accounting policies.

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Description of risks that arise due to the volume of business transacted with a particular supplier or reliance placed on that supplier. At a minimum, the description informs financial statement users of the general nature of the risk.

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