Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Operating expenses:
Research and development	$ 14,904	$ 22,449
General and administrative	12,908	11,603
Total operating expenses	27,812	34,052
Loss from operations	(27,812)	(34,052)
Other income (expense):
Interest expense	(908)	(1,228)
Other income (expense), net	(748)	627
Total other expense	(1,656)	(601)
Loss before income tax expense	(29,468)	(34,653)
Income tax expense	(32)	(91)
Net loss	$ (29,500)	$ (34,744)
Net loss per share - basic and diluted	$ (0.96)	$ (5.19)
Basic and diluted weighted average shares outstanding	30,776	6,691