Laduviglusib (CHIR-99021, CT99021) is a GSK-3α and GSK-3β inhibitor with IC50 of 10 nM and 6.7 nM, respectively. CHIR99201 does not exhibit cross-reactivity against cyclin-dependent kinases (CDKs) and shows a 350-fold selectivity toward GSK-3β compared to CDKs. CHIR99021 functions as a Wnt/β-catenin activator and induces autophagy.