ORGANIZATION, BASIS OF PRESENTATION, AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,603	$ 1,763
Less: accumulated depreciation	(1,591)	(1,574)
Property and equipment, net	$ 12	189
Leasehold improvements
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	5 years
Property and equipment, gross	$ 0	167
Lab equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	5 years
Property and equipment, gross	$ 530	530
Manufacturing equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	5 years
Property and equipment, gross	$ 138	138
Computer and office equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 841	834
Software
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	3 years
Property and equipment, gross	$ 94	$ 94
Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	3 years
Minimum | Computer and office equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	3 years
Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	5 years
Maximum | Computer and office equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	5 years