– PF-06843195 is a highly selective PI3K? inhibitor with an IC50 of 18 nM in Rat1 fibroblasts. The Kis of PF-06843195 for PI3K? and PI3K? in biochemical kinase assay are less than 0.018 nM and 0.28 nM, respectively. PF-06843195 has great suppression of the PI3K/mTOR signaling pathway and durable antitumor efficacy.