CONDENSED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 47,077	$ 72,428
Short-term investments	42,627	44,261
Accounts receivable	4,394	502
Inventory	3,487	0
Prepaid expenses and other current assets	16,640	16,458
Total current assets	114,225	133,649
Right-of-use assets	11,910	12,752
Property and equipment, net	2,045	2,362
Other assets	1,228	1,150
Total assets	129,408	149,913
Current liabilities:
Accounts payable	5,030	4,277
Accrued compensation and benefits	6,304	5,422
Current portion of long-term debt	26,139	32,264
Current portion of operating lease liability	3,592	3,492
Accrued expenses and other current liabilities	6,778	7,366
Total current liabilities	47,843	52,821
Operating lease liability, net of current portion	8,812	9,748
Deferred revenue, non-current	8,563	4,727
Total liabilities	65,218	67,296
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.0001 par value; 5,000,000 shares authorized; no shares issued and outstanding as of March 31, 2022 and December 31, 2021, respectively.	0	0
Common stock, $0.0001 par value; 300,000,000 shares authorized; 136,330,360 and 130,182,535 shares issued and outstanding as of March 31, 2022 and December 31, 2021, respectively.	14	13
Additional paid-in capital	805,265	795,540
Accumulated deficit	(741,001)	(712,930)
Accumulated other comprehensive loss	(88)	(6)
Total stockholders’ equity	64,190	82,617
Total liabilities and stockholders’ equity	$ 129,408	$ 149,913