Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue:
Revenue from Contract with Customer, Including Assessed Tax	$ 892	$ 4,046	$ 9,862
Revenue	892	4,046	9,862
Operating expenses:
Research and development	48,749	19,863	14,540
General and administrative	21,890	15,202	6,187
Impairment of intangible assets	3,005	0	0
Restructuring charges (reversals)	0	(849)	4,920
Total operating expenses	73,644	34,216	25,647
Operating loss	(72,752)	(30,170)	(15,785)
Other income (expense):
Interest income	81	75	149
Interest expense	0	0	(315)
Non-cash interest expense related to sale of future royalties	(1,480)	(1,874)	(2,073)
Gain on sale of equipment	0	0	1
Gain on remeasurement of future royalty liability	3,789	0	0
Loss on debt extinguishment	0	0	(100)
Foreign exchange loss, net	(1)	(13)	(32)
Loss before income taxes	(70,363)	(31,982)	(18,155)
Provision for income taxes	107	238	490
Net loss	$ (70,470)	$ (32,220)	$ (18,645)
Net loss per share – basic and diluted (in dollars per share)	$ (0.58)	$ (0.36)	$ (0.86)
Shares used to compute net loss per share – basic and diluted (in shares)	121,453,723	88,295,762	21,569,523
Comprehensive loss:
Net loss	$ (70,470)	$ (32,220)	$ (18,645)
Unrealized loss on available-for-sale investments, net of tax	(74)	0	0
Comprehensive loss	(70,544)	(32,220)	(18,645)
Customer Service Contracts [Member]
Revenue:
Revenue from Contract with Customer, Including Assessed Tax	13	198	406
Revenue	13	198	406
Government Contract [Member]
Revenue:
Revenue from Contract with Customer, Including Assessed Tax	0	0	(20)
Revenue	0	0	(20)
Royalty [Member]
Revenue:
Revenue from Contract with Customer, Including Assessed Tax	0	2,962	4,446
Revenue	0	2,962	4,446
Non Cash Royalty Revenue [Member]
Revenue:
Revenue from Contract with Customer, Including Assessed Tax	879	886	5,030
Revenue	$ 879	$ 886	$ 5,030