Resminostat is a potent inhibitor of histone deacetylases (HDAC) 1, 3 and 6 with IC₅₀ ranging from 43–72 nM. It induces hyperacetylation of histone H4, abrogates cell growth and induces apoptosis in multiple myeloma cells with an IC₅₀ of 2.5-3 µM. It inhibits cell proliferation, induces G0/G1 cell cycle arrest, decreases levels of cyclin D1, cdc25a, Cdk4 and pRb and upregulates p21.
