UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Revenue:
Collaboration revenue	$ 4,847	$ 434	$ 14,030	$ 459
Total revenue	4,847	434	14,030	459
Operating expenses:
Research and development expense	7,008	3,433	13,083	6,828
General and administrative expense	2,229	1,985	4,803	4,193
Total operating expenses	9,237	5,418	17,886	11,021
Operating loss	(4,390)	(4,984)	(3,856)	(10,562)
Other income (expense), net:
Dividend income	4	82	43	187
Interest income	267	1	627	2
Interest expense	0	(203)	(128)	(386)
Other income (expense), net	(192)	(116)	153	253
Total other income (expense), net	79	(236)	695	56
Net loss	$ (4,311)	$ (5,220)	$ (3,161)	$ (10,506)
Basic and diluted loss per common share (in usd per share)	$ (0.05)	$ (0.12)	$ (0.04)	$ (0.24)
Weighted average basic and diluted common shares outstanding (in shares)	87,174,533	44,368,174	87,126,847	44,363,115