Schedule of Other Accrued Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Payables And Accruals [Abstract]
Manufacturing	$ 1,381	$ 2,238
Biogen	868
Pre-clinical	773
Professional and consulting services	509	3,979
Clinical	361	291
Other	180	235
Total other accrued liabilities	$ 4,072	$ 6,743

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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