Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 224,572	$ 219,544
Short-term investments, available-for-sale	325,897	884,497
Prepaid expenses and other current assets	18,996	35,266
Total current assets	569,465	1,139,307
Investments, available-for-sale	160,796	0
Land, property and equipment, net	19,125	22,090
Other non-current assets	35,319	29,323
Total assets	784,705	1,190,720
Current liabilities:
Accounts payable and other accrued liabilities	32,135	35,351
Accrued clinical and preclinical study fees	29,129	18,325
Current portion of lease financing obligations	5,052	4,401
Total current liabilities	66,316	58,077
Lease financing obligations, less current portion	36,159	41,211
Other long-term liabilities	8,993	10,963
Commitments and contingencies
Stockholders' equity:
Preferred stock, $0.0001 par value, 7,500,000 shares authorized, no shares issued and outstanding at December 31, 2021, and 2020	0	0
Common stock, $0.0001 par value, 147,000,000 shares authorized at December 31, 2021, and 2020; 61,564,122 and 58,611,210 shares issued and outstanding at December 31, 2021 and 2020, respectively	6	6
Additional paid-in capital	2,797,675	2,587,494
Accumulated other comprehensive (loss) income	(280)	700
Accumulated deficit	(2,124,164)	(1,507,731)
Total stockholders' equity	673,237	1,080,469
Total liabilities and equity	$ 784,705	$ 1,190,720