Condensed Consolidated Balance Sheets - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 102,304,000	$ 298,887,000
Short-term investment securities	59,374,000	15,876,000
Accounts receivable, net		1,389,000
Prepaid research and development	4,237,000	11,929,000
Other current assets	2,359,000	2,884,000
Total current assets	168,274,000	330,965,000
Restricted cash	1,273,000	1,264,000
Long-term investment securities	12,404,000	35,533,000
Right of use assets	8,888,000	8,629,000
Leasehold interest, net	1,627,000	1,839,000
Equipment, net	307,000	600,000
Goodwill	799,000	799,000
Total assets	193,572,000	379,629,000
Current liabilities:
Accounts payable and accrued expenses	42,019,000	51,294,000
Other current liabilities	1,169,000	1,512,000
Loan payable - current portion	0	975,000
Lease liability - current portion	1,581,000	1,437,000
Accrued compensation	8,432,000	10,166,000
Total current liabilities	53,201,000	65,384,000
Deferred revenue, net of current portion	305,000	457,000
Loan payable - non-current	71,135,000	66,788,000
Lease liability - non-current	10,344,000	9,847,000
Total liabilities	134,985,000	142,476,000
Commitments and contingencies
Stockholders' equity:
Common stock, $0.001 par value per share (175,000,000 shares authorized, 145,399,144 and 143,292,043 shares issued, 145,357,835 and 143,250,734 shares outstanding at September 30, 2022 and December 31, 2021, respectively)	146,000	143,000
Additional paid-in capital	1,585,708,000	1,565,942,000
Treasury stock, at cost, 41,309 shares at September 30, 2022 and December 31, 2021	(234,000)	(234,000)
Accumulated deficit	(1,527,033,000)	(1,328,698,000)
Total stockholders' equity	58,587,000	237,153,000
Total liabilities and stockholders' equity	$ 193,572,000	$ 379,629,000