Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 7,253	$ 50,288
Marketable securities	19,033	0
Accounts receivable	0	49
Inventory	107	41
Prepaid expenses and other current assets	5,194	4,205
Total current assets	31,587	54,583
Restricted cash	58	58
Right-of-use assets	4,808	3,250
Property and equipment, net	8,089	5,172
Total assets	44,542	63,063
Current liabilities:
Accounts payable	4,526	1,923
Accrued liabilities	2,566	3,610
Operating lease obligations, current portion	440	347
Finance lease obligations, current portion	123	146
Total current liabilities	7,655	6,026
Operating lease obligations, net of current portion	5,858	4,370
Finance lease obligations, net of current portion	55	97
Total notes payable	15,551	14,484
Convertible notes payable	4,709	4,598
Common stock warrant liability	167	474
Clene Nanomedicine contingent earn-out	9,847	18,100
Initial Shareholders contingent earn-out	1,263	2,317
TOTAL LIABILITIES	45,105	50,466
Commitments and contingencies (Note 11)
Stockholders’ equity:
Common stock, $0.0001 par value: 150,000,000 shares authorized; 63,246,545 and 62,312,097 shares issued and outstanding at June 30, 2022 and December 31, 2021, respectively	6	6
Additional paid-in capital	180,534	175,659
Accumulated deficit	(181,189)	(163,301)
Accumulated other comprehensive income	86	233
TOTAL STOCKHOLDERS’ EQUITY	(563)	12,597
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY (DEFICIT)	$ 44,542	$ 63,063