GDC-0032

GDC-0032 is an orally bioavailable, potent and selective inhibitor of Class I PI3Kα, δ and γ isoforms, with 30 fold less inhibition of the PI3K β isoform relative to the PI3Kα isoform. GDC-0032 inhibits MCF7-neo/HER2 cells proliferation with IC50 of 2.5 nM. The combination of GDC-0032 with tamoxifen enhances the efficacy of tamoxifen in vivo (102%TGI for GDC-0032). GDC-0032 is currently in a phase I clinical trial.