VX-702 is a highly specific p38α MAPK inhibitor, 14-fold higher selectivity for the p38α than p38β. VX-702 is a small molecule investigational oral anti-cytokine therapy for treatment of inflammatory diseases, specifically rheumatoid arthritis (RA).

p38α:4 nM-20 nM

HDAC enzyme assay in vitro: The deacetylase enzyme assay is based on a homogeneous fluorescence release assay. Purified recombinant HDAC enzymes are incubated with MGCD0103 diluted in various concentrations for 10 minutes in assay buffer [25 mM HEPES (pH 8.0), 137 mM NaCl, 1 mM MgCl2, 2.7 mM KCl] at room temperature. The substrate Boc-Lys(ε-Ac)-AMC is added to the reaction for further incubation at 37 °C. The concentration of the substrate and the incubation time varies for different isotypes of HDAC enzymes. A 20-min trypsin incubation at room temperature allows the release of the fluorophore from the deacetylated substrate. The fluorescent signal is detected by fluorometer at excitation of 360 nm, emission of 470 nm, and cutoff at 435 nm.