Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
CURRENT ASSETS:
Cash and cash equivalents	$ 92,503	$ 18,850
Prepaid expenses and other current assets	9,432	7,301
Investments	61,806	20,004
Total current assets	163,741	46,155
Operating lease right-of-use asset	1,942	2,035
Security deposits and leasehold improvements	199	199
TOTAL ASSETS	165,882	48,389
CURRENT LIABILITIES:
Current portion of operating lease liabilities	364	356
Accounts payable	1,606	8,793
Accrued expenses and other current liabilities	6,496	4,950
Total current liabilities	8,466	14,099
NONCURRENT LIABILITIES:
Noncurrent portion of operating lease liabilities	1,588	1,683
Total noncurrent liabilities	1,588	1,683
Total liabilities	10,054	15,782
STOCKHOLDERS’ EQUITY (DEFICIT):
Common stock, $0.0001 par value; 100,000,000 and 100,000,000 shares authorized as of March 31, 2020 and December 31, 2019, respectively; 21,969,277 shares and 18,531,560 shares issued and outstanding as of March 31, 2020 and December 31, 2019, respectively	2	1
Additional paid-in capital	234,876	99,378
Accumulated other comprehensive loss	89	(2)
Accumulated deficit	(79,139)	(66,770)
Total stockholders' equity	155,828	32,607
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	$ 165,882	$ 48,389