CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 4,581	$ 39,898
Investments	32,191	23,720
Trade accounts receivable, net	2,935	2,320
Inventory	5,304	5,067
Prepaid expenses	1,429	768
Other current assets	1,619	1,558
Total current assets	48,059	73,331
Property and equipment, net	4,097	5,389
Finance lease assets, net	2,538	0
Operating lease right of use assets, net	2,181	2,510
Other non-current assets	1,851	1,817
Total assets	58,726	83,047
Current liabilities:
Accounts payable	2,221	1,983
Accrued liabilities	5,654	2,853
Accrued interest	746	909
Deferred revenue	335	451
Current portion of long-term debt	84	80
Finance lease, current	953	0
Operating lease, current	732	669
Total current liabilities	10,725	6,945
Finance lease, non-current	1,383	0
Operating lease, non-current	1,997	2,381
Other non-current liabilities	757	808
Convertible notes	105,828	107,984
Total liabilities	120,690	118,118
Commitments and contingencies
Stockholders’ deficit:
Preferred shares, $0.001 par value	4	4
Common stock, $0.001 par value	80	68
Contributed capital	560,185	580,652
Treasury stock	(45,067)	(45,067)
Accumulated deficit	(576,734)	(570,668)
Accumulated other comprehensive loss	(432)	(60)
Total stockholders’ deficit	(61,964)	(35,071)
Total liabilities and stockholders’ deficit	$ 58,726	$ 83,047