Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenues:
Total revenue	$ 525	$ 847	$ 2,228	$ 8,398
Operating expenses:
Research and development	(8,074)	(9,717)	(15,612)	(19,996)
General and administrative	(13,427)	(8,837)	(26,836)	(18,973)
Total operating expenses	(21,501)	(18,554)	(42,448)	(38,969)
Loss from operations	(20,976)	(17,707)	(40,220)	(30,571)
Other income (expense):
Other income (expense), net	56	(141)	126	(118)
Interest income	72	19	82	28
Interest expense	(904)	(7)	(1,803)	(11)
Loss before income taxes	(21,752)	(17,836)	(41,815)	(30,672)
Income tax benefit (expense)	45	48	(109)	(458)
Net loss	$ (21,707)	$ (17,788)	$ (41,924)	$ (31,130)
Loss per share
Basic and Diluted ($ per share)	$ (0.30)	$ (0.44)	$ (0.59)	$ (0.80)
Weighted average number of shares:
Basic and Diluted (in shares)	72,526,441	40,515,920	70,624,583	38,723,718
Collaboration revenue
Revenues:
Total revenue			$ 1,000	$ 6,500
Research premium and grant revenue
Revenues:
Total revenue	$ 525	$ 847	$ 1,228	$ 1,898