PFI-1 is a BET bromodomain inhibitor that exhibits inhibitory activity at BRD2 and BRD4. In an AlphaScreen assay it has been shown to inhibit BRD2 bromodomain 2 and BRD4 bromodomain 1 with IC50 values of 98 nM and 0.22 μM, respectively.http://www.creative-enzymes.com/product/PFI1_2365.html