CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 44,580	$ 35,781
Investments	24,251	32,488
Trade accounts receivable	2,114	1,550
Inventory	9,572	9,216
Prepaid expenses	1,680	1,172
Other current assets	1,498	1,780
Total current assets	83,695	81,987
Property and equipment, net	5,548	6,135
Right of use assets	2,848	3,183
Other non-current assets	1,898	2,120
Total assets	93,989	93,425
Current liabilities:
Accounts payable	1,877	1,290
Accrued liabilities	3,832	2,991
Accrued interest	1,262	1,262
Deferred revenue	282	376
Current portion of long-term debt	1,452	553
Current operating lease liability	612	497
Total current liabilities	9,317	6,969
Non-current operating lease liability	2,747	3,063
Other non-current liabilities	580	335
Long-term debt	3,805	4,659
Convertible notes	147,290	141,211
Total liabilities	163,739	156,237
Commitments and contingencies
Stockholders’ deficit:
Preferred shares, $0.001 par value	0	0
Common stock, $0.001 par value	61	58
Contributed capital	514,122	475,072
Treasury stock	(45,067)	(45,067)
Accumulated deficit	(538,879)	(492,966)
Accumulated other comprehensive income	13	91
Total stockholders’ deficit	(69,750)	(62,812)
Total liabilities and stockholders’ deficit	$ 93,989	$ 93,425