Condensed Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Current Assets:
Cash and cash equivalents	$ 80,289	$ 4,185
Restricted cash	20	20
Prepaid expenses and other current assets	3,147	921
Total current assets	83,456	5,126
Total assets	83,456	5,126
Current Liabilities:
Accounts payable	3,249	2,234
Accrued expenses	3,736	3,100
Series B preferred stock tranche right liability		300
Total current liabilities	6,985	5,634
Total liabilities	6,985	5,634
Commitments and Contingencies (Note 10)
Redeemable Noncontrolling Interest, Equity, Preferred, Carrying Amount	194,268	96,928
Stockholders' Deficit:
Common stock, $0.0001 par value; 146,000,000 and 76,000,000 shares authorized as of June 30, 2020 and December 31, 2019, respectively; 1,488,489 shares issued and outstanding as of June 30, 2020 and December 31, 2019;	1	1
Additional paid-in capital
Accumulated deficit	(117,798)	(97,437)
Total stockholders' deficit	(117,797)	(97,436)
Total liabilities, redeemable convertible preferred stock and stockholders' deficit	83,456	5,126
Series A Redeemable Convertible Preferred Stock [Member]
Current Liabilities:
Redeemable Noncontrolling Interest, Equity, Preferred, Carrying Amount	33,479	32,482
Series B Redeemable Convertible Preferred Stock [Member]
Current Liabilities:
Series B preferred stock tranche right liability	300
Redeemable Noncontrolling Interest, Equity, Preferred, Carrying Amount	75,314	$ 64,446
Series C Redeemable Convertible Preferred Stock [Member]
Current Liabilities:
Redeemable Noncontrolling Interest, Equity, Preferred, Carrying Amount	$ 85,475