Condensed Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 105,642	$ 69,466
Short-term investments	17,127	78,016
Accounts receivable, net	10,976	9,070
Inventories	16,049	9,989
Prepaid expenses and other current assets	4,662	6,787
Total current assets	154,456	173,328
Property and equipment, net	5,132	2,844
Restricted cash	232	310
Other non-current assets	5,711	2,832
Total assets	165,531	179,314
Current liabilities:
Accounts payable	4,908	2,598
Accrued liabilities	16,011	16,957
Total current liabilities	20,919	19,555
Long-term debt	48,652	48,533
Other liabilities	7,781	3,726
Total liabilities	77,352	71,814
Commitments and contingencies (Note 7)
Preferred stock, $0.001 par value
Shares authorized: 5,000,000 at September 30, 2021 and December 31, 2020 Shares issued and outstanding: none at September 30, 2021 and December 31, 2020
Common stock, $0.001 par value
Shares authorized: 100,000,000 at September 30, 2021 and December 31, 2020 Shares issued and outstanding: 34,854,822 and 34,249,649 at September 30, 2021 and December 31, 2020, respectively	35	34
Additional paid-in capital	362,152	346,318
Accumulated other comprehensive income	1	39
Accumulated deficit	(274,009)	(238,891)
Total stockholders’ equity	88,179	107,500
Total liabilities and stockholders’ equity	$ 165,531	$ 179,314