Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 64,788	$ 75,975
Short-term marketable securities	71,612	0
Prepaid expenses and other current assets	1,649	1,156
Total current assets	138,049	77,131
Other assets	69	20
Total assets	138,118	77,151
Current liabilities:
Accounts payable	947	1,373
Accrued expenses and other current liabilities	8,422	969
Total current liabilities	9,369	2,342
Other liabilities	23
Total liabilities	9,392	2,342
Commitments and contingencies (Note 12)
Redeemable convertible preferred stock (Series A and B), $0.0001 par value; no shares authorized, issued and outstanding as of December 31, 2019; 64,730,410 shares authorized, issued and outstanding as of December 31, 2018; aggregate liquidation preference of $0 and $96,358 as of December 31, 2019 and December 31, 2018, respectively		124,728
Stockholders’ equity (deficit):
Common stock, $0.0001 par value, 150,000,000 shares authorized as of December 31, 2019 and 75,000,000 shares authorized as of December 31, 2018; 28,567,837 and 238,986 shares issued and outstanding as of December 31, 2019 and December 31, 2018, respectively	3
Additional paid-in capital	259,049	36,646
Accumulated other comprehensive loss	(6)
Accumulated deficit	(130,320)	(86,565)
Total stockholders’ equity (deficit)	128,726	(49,919)
Total liabilities, redeemable convertible preferred stock and stockholders’ equity (deficit)	$ 138,118	$ 77,151