CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Operating expenses:
Research and development	$ 8,589	$ 6,158	$ 23,098	$ 15,657
General and administrative	4,383	2,387	13,726	5,374
Loss on transfer of non-financial assets (Note 16)	4,004	0	4,004	0
Total operating expenses	16,976	8,545	40,828	21,031
Loss from operations	(16,976)	(8,545)	(40,828)	(21,031)
Other income (expense):
Interest income	464	51	927	187
Interest expense	(688)	(148)	(1,599)	(484)
Change in fair value of preferred stock warrant liability	0	45	(288)	(264)
Change in fair value of derivative liability	0	(5)	183	(411)
Loss on extinguishment of debt	(566)	0	(566)	0
Other income (expense)	52	0	201	0
Total other income (expense), net	(738)	(57)	(1,142)	(972)
Net loss	(17,714)	(8,602)	(41,970)	(22,003)
Accruing dividends on Series A convertible preferred stock	0	(756)	(592)	(2,244)
Adjustment to accumulated deficit in connection with repurchase of Series Seed convertible preferred stock	0	0	0	(22)
Net loss attributable to common stockholders	$ (17,714)	$ (9,358)	$ (42,562)	$ (24,269)
Net loss per share attributable to common stock holders- basic and diluted (usd per share)	$ (1.22)	$ (20.39)	$ (4.31)	$ (52.92)
Weighted average common shares outstanding—basic and diluted (in shares)	14,562,000	459,000	9,866,000	459,000