Note 4 - Balance Sheet Components - Property and Equipment, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Property and equipment, gross	$ 6,406	$ 2,053
Less: accumulated depreciation	(979)	(573)
Property and equipment, net	5,427	1,480
Laboratory Equipment [Member]
Property and equipment, gross	3,389	1,759
Office Equipment [Member]
Property and equipment, gross	382	294
Leasehold Improvements [Member]
Property and equipment, gross	1,057	0
Construction in Progress [Member]
Property and equipment, gross	$ 1,578	$ 0

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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