Income Taxes - Summary of Reconciliation of Statutory Federal Rate and Effective Rate for Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Income Tax Disclosure [Abstract]
Tax computed at federal statutory rate	$ (3,533)	$ (3,929)
State income tax, net of federal benefit	(823)	(714)
Executive compensation	509	0
Stock-based compensation	2,662	893
Research credits	(35)	(421)
Change in tax rate	(282)	(193)
Removal of net operating losses and research development credits	3,269	5,091
Other	(215)	70
Valuation allowance	(1,552)	(797)
Provision (benefit) for income taxes	$ 0	$ 0
Tax computed at federal statutory rate	21.00%	21.00%
State income tax, net of federal benefit	4.90%	3.80%
Executive compensation	(3.00%)	0.00%
Stock-based compensation	(15.80%)	(4.80%)
Research credits	0.10%	2.20%
Change in tax rate	1.70%	1.00%
Removal of net operating losses and research development credits	(19.40%)	(27.20%)
Other	1.40%	(0.30%)
Valuation allowance	9.10%	4.20%
Provision (benefit) for income taxes	0.00%	0.00%

Effective income tax rate reconciliation, executive compensation, amount.

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Effective income tax reconciliation, employee compensation, percentage.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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