GDC-0349 is a potent and selective ATP-competitive mTOR inhibitor with a K_i of 3.8 nM. GDC-0349 inhibits of both mTORC1 and mTORC2 complexes. IC50 & Target: Ki: 3.8 nM (mTOR)^[1]
mTORC1, mTORC2^[1] In Vitro: GDC-0349 (Compound 8h) is a remarkably selective mTOR inhibitor, with less than 25% inhibition of 266 kinases, including all isoforms of PI3K when tested at 1 μM^[1]. In Vivo: When dosed orally once daily in athymic mice in a MCF7-neo/Her2 tumor xenograft model (PI3K mutation), GDC-0349 (Compound 8h) inhibits tumor growth in a dose-dependent manner, achieving stasis (99% TGI) at the maximum tolerated dose. Body weight change is less than 10% up to the highest dose. GDC-0349 is also efficacious in other xenograft models, including PC3 (PTEN null) and 786-0 (VHL mutant). Similar levels of tumor growth inhibition are achieved when GDC-0349 is administered once every three days at higher doses compared to once every day. GDC-0349 has ~10-fold reduced free plasma clearance in both mice (100 mL/min/kg) and rats (171 mL/min/kg in rat)^[1].