Note 4 - Property and Equipment, Net - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, plant, and equipment, gross	$ 442	$ 390
Less: accumulated depreciation	(258)	(181)
Property and equipment, net	184	209
Office Equipment [Member]
Property, plant, and equipment, gross	181	150
Laboratory Equipment [Member]
Property, plant, and equipment, gross	121	114
Automobiles [Member]
Property, plant, and equipment, gross	24	23
Leasehold Improvements [Member]
Property, plant, and equipment, gross	$ 116	$ 103

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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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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