Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Revenues:
License and other revenues		$ 346
Expenses:
Research and development	8,041	10,545
General and administrative	3,997	4,224
Impairment of licensed technology		1,355
Impairment of right-of-use lease assets		1,561
Impairment of construction-in-progress		3,252
Total expenses	12,038	20,937
Loss from operations	(12,038)	(20,591)
Interest income	364	7
Interest expense	(101)	(201)
Change in fair value of warrant liabilities	2,265	(1,253)
Other income (loss)	403	(6)
Net loss	$ (9,107)	$ (22,044)
Basic and diluted loss per common share	$ (0.54)	$ (3.80)
Weighted average number of common shares outstanding – basic and diluted	16,904,024	5,795,107
Other comprehensive income (loss):
Change in unrealized gains (losses) related to available-for-sale debt securities	$ 64	$ (3)
Comprehensive loss	$ (9,043)	$ (22,047)