Condensed Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 469,167	$ 554,101
Marketable securities	645,610	568,407
Prepaid and other current assets	7,135	8,171
Total current assets	1,121,912	1,130,679
Property and equipment, net	2,509	2,604
Right-of-use lease assets	3,056	3,357
Other assets	107	73
Total assets	1,127,584	1,136,713
Current liabilities:
Accounts payable	6,784	5,225
Accrued expenses and other current liabilities	12,283	9,183
Accrued compensation	3,865	8,588
Current portion of operating lease liabilities	1,439	1,396
Total current liabilities	24,371	24,392
Operating lease liabilities, long-term	2,048	2,423
Commitments and contingencies (Note 8)
Stockholders' equity:
Preferred stock, $0.0001 par value;10,000,000 shares authorized at March 31, 2021 and December 31, 2020, zero shares outstanding at March 31, 2021 and December 31, 2020
Common stock, $0.0001 par value; 200,000,000 shares authorized at March 31, 2021 and December 31, 2020; 49,117,040 and 48,678,540 shares issued and outstanding at March 31, 2021 and December 31, 2020, respectively	5	5
Additional paid-in capital	1,416,817	1,389,860
Accumulated other comprehensive income	23	209
Accumulated deficit	(315,680)	(280,176)
Total stockholders' equity	1,101,165	1,109,898
Total liabilities and stockholders’ equity	$ 1,127,584	$ 1,136,713