Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 24,205	$ 14,437
Accounts receivable	750	905
Inventories	2,843	2,957
Other current assets	328	237
Total current assets	28,126	18,536
Property, plant and equipment, net	1,188	1,200
Operating lease right-of-use asset	1,082	255
Other assets	21	21
TOTAL ASSETS	30,417	20,012
Current liabilities
Accounts payable	1,414	1,097
Accrued compensation	1,664	2,192
Current portion of operating lease liability	167	206
Current portion of finance lease liability	26	24
Other current liabilities	36	66
Total current liabilities	3,307	3,585
Operating lease liability	956	55
Finance lease liability	28	54
Other long-term liability	179	0
Total liabilities	4,470	3,694
Commitments and contingencies
Stockholders' equity
Preferred stock	0	0
Common stock as of December 31, 2021 and December 31, 2020, par value $0.0001 per share; authorized 100,000,000 shares, issued and outstanding 10,537,606 and 2,736,060, respectively	1	0
Additional paid-in capital	278,873	249,663
Accumulated other comprehensive loss:
Foreign currency translation adjustment	(11)	(7)
Accumulated deficit	(252,916)	(233,338)
Total stockholders' equity	25,947	16,318
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	30,417	20,012
Series A Junior Participating Preferred Stock [Member]
Stockholders' equity
Preferred stock	0	0
Series F Convertible Preferred Stock [Member]
Stockholders' equity
Preferred stock	$ 0	$ 0