SUPPLEMENTAL FINANCIAL INFORMATION - Summary of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Supplemental Financial Information [Abstract]
Research and development service agreements, current	$ 4,363	$ 4,841
Research and development service agreements, noncurrent	56	75
Research and development service agreements	4,419	4,916
Prepaid insurance	481	858
Other receivables	376	345
Dues and subscriptions	331	230
Right-of-use asset	$ 236	$ 266
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other assets, long-term	Other assets, long-term
Property and equipment, net	$ 137	$ 73
Other, current	248	475
Other, noncurrent	75	72
Other	323	547
Prepaid expenses and other current assets	5,799	6,749
Other assets, long-term	504	486
Total	6,303	7,235
Accumulated depreciation, property and equipment	$ 100	$ 100