Note 4 - Balance Sheet Components - Property and Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Property and equipment, gross	$ 9,304	$ 7,906
Less: accumulated depreciation	(1,675)	(1,305)
Property and equipment, net	7,629	6,601
Laboratory Equipment [Member]
Property and equipment, gross	5,537	5,057
Office Equipment [Member]
Property and equipment, gross	526	481
Leasehold Improvements [Member]
Property and equipment, gross	1,063	1,063
Construction in Progress [Member]
Property and equipment, gross	$ 2,178	$ 1,305

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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