SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of segment reporting (Details) - USD ($) $ in Thousands		12 Months Ended
	Jan. 06, 2023	Dec. 31, 2024	Dec. 31, 2023
Research and development
General and administrative		$ 16,106	$ 14,904
Restructuring charges	$ 5,100	0	5,107
Net loss		(44,485)	(45,704)
Reconciliation of segment net loss
Net loss		$ (44,485)	$ (45,704)
Other segment Item description		(a) Other segment items in segment net loss includes other income (expense), net and income tax expense	(a) Other segment items in segment net loss includes other income (expense), net and income tax expense
Single reportable segment | Operating segments
Research and development
EO-3021 clinical program		$ 13,274	$ 6,095
Seribantumab clinical program		3,692	10,326
Discovery, preclinical, and other unallocated research and development expense		3,356	1,445
Personnel expenses (including stock-based compensation)		8,275	7,568
General and administrative		16,106	14,904
Restructuring charges			5,107
Other segment items		(218)	259
Net loss		(44,485)	(45,704)
Reconciliation of segment net loss
Net loss		$ (44,485)	$ (45,704)