Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Statement [Abstract]
Revenues	$ 13,287,000	$ 8,260,000	$ 39,754,000	$ 38,700,000
Costs and expenses:
Manufacture and supply	4,400,000	2,978,000	11,623,000	10,176,000
Research and development	4,726,000	7,260,000	12,647,000	15,461,000
Selling, general and administrative	12,129,000	11,803,000	38,494,000	40,310,000
Total costs and expenses	21,255,000	22,041,000	62,764,000	65,947,000
Loss from operations	(7,968,000)	(13,781,000)	(23,010,000)	(27,247,000)
Other income/(expenses):
Interest expense	(2,787,000)	(2,778,000)	(8,305,000)	(8,296,000)
Interest expense related to the sale of future revenue, net	(3,767,000)	0	(10,567,000)	0
Interest and other (expense) income, net	(33,000)	8,000	288,000	128,000
Net loss before income taxes	(14,555,000)	(16,551,000)	(41,594,000)	(35,415,000)
Income taxes	0	0	0	0
Net loss	(14,555,000)	(16,551,000)	(41,594,000)	(35,415,000)
Comprehensive loss	$ (14,555,000)	$ (16,551,000)	$ (41,594,000)	$ (35,415,000)
Net loss per share - basic (in dollars per share)	$ (0.37)	$ (0.49)	$ (1.12)	$ (1.05)
Net loss per share - diluted (in dollars per share)	$ (0.37)	$ (0.49)	$ (1.12)	$ (1.05)
Weighted-average number of common shares outstanding - basic (in shares)	39,224,863	33,619,379	37,297,892	33,592,846
Weighted-average number of common shares outstanding - diluted (in shares)	39,224,863	33,619,379	37,297,892	33,592,846