Infinity beyond a checkpoint
Infinity's PI3Kγ inhibitor counters tumor immune suppression via myeloid cells
As pan-PI3K inhibitors have had limited success in the clinic for cancer, researchers are increasingly exploring whether better results might come from teasing apart the activity of the different isoforms. Infinity Pharmaceuticals Inc. has found that specifically inhibiting PI3Kγ - which is highly expressed in myeloid cells - can improve the effectiveness of checkpoint inhibitors, and the company is gearing up to test its compound in the clinic next year.
Last month, Infinity presented data on the anti-tumor activity of its PI3Kγ inhibitor IPI-549 in models of lung, colon and breast cancer at the International Cancer Immunotherapy Conference. According to Julian Adams, Infinity's president of R&D, IPI-549 slows tumor growth by opposing the migration and polarization of myeloid-derived suppressor cells (MDSCs), enabling the activation of anti-tumor T cells...