KB02-JQ1 is a highly selective and PROTAC-based BRD4 degrader (molecular glue), but does not degrade BRD2 or BRD3. KB02-JQ1 promotes BRD4 degradation by covalently modifying DCAF16 (E3 ligase) and can improve the durability of protein degradation in biological systems. JQ1 binds ubiquitin E3 ligase ligand KB02 via a linker to form KB02-JQ1[1].