Ribociclib succinate hydrate is a highly specific CDK4 6 inhibitor (IC50s: 10 nM and 39 nM, respectively). It also is over 1,000-fold less potent against the cyclin B CDK1 complex.
Ribociclib hydrochloride is a highly specific CDK4 6 inhibitor (IC50: 10 nM and 39 nM, respectively). It is over 1,000-fold less potent against the cyclin B CDK1 complex.