ALV1 is a molecular glue degrader for Ikaros ( IKZF1 ) and Helios ( IKZF2 ) , with DC 50 values of 2.5 nM and 10.3 nM, respectively. ALV1 binds CRBN with an IC 50 of 0.55 µM. ALV1 induces CRBN-Helios dimerization. ALV1 can be used to study the properties and functions of T reg cells.