Note 3 - Property and Equipment, Net - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Property, plant, and equipment, gross	$ 382	$ 386
Less: accumulated depreciation	(145)	(104)
Property and equipment, net	237	282
Office Equipment [Member]
Property, plant, and equipment, gross	141	143
Laboratory Equipment [Member]
Property, plant, and equipment, gross	115	111
Automobiles [Member]
Property, plant, and equipment, gross	23	23
Leasehold Improvements [Member]
Property, plant, and equipment, gross	$ 103	$ 109

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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