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Milestone payments received.

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Amount of cash and cash equivalent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

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The net result for the period of deducting operating expenses from operating revenues.

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The number of positions eliminated during the period as a percentage of total positions eliminated during the period in connection with the restructuring plan(s).

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Nature of the Business and Basis of Presentation - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	Feb. 12, 2026	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Oct. 31, 2026	Dec. 31, 2025
Nature Of Business And Basis Of Presentation [Line Items]
Entity incorporated month and year				2010-10
Restructuring and related cost, number of positions eliminated, period percent	30.00%
Restructuring costs				$ 914
Severance costs				$ 718
Entity incorporation, state or country code				DE
Loss from operations		$ (16,152)	$ (22,477)	$ (58,332)	$ (74,594)
Milestone Payment date		Oct. 01, 2026		Oct. 01, 2026
Accumulated deficit		$ (1,004,021)		$ (1,004,021)			$ (972,403)
Cash and cash equivalents		$ 17,528		$ 17,528			45,766
Subsequent Event [Member]
Nature Of Business And Basis Of Presentation [Line Items]
Milestone Payments Received						$ 12,500
CARB-X [Member] \| Maximum [Member]
Nature Of Business And Basis Of Presentation [Line Items]
Grant Received for Clinical Development							$ 3,583