Dr. Rugo on PI3K and mTOR Inhibitors for Breast Cancer

Hope S. Rugo, MD, professor of medicine and director of breast oncology and clinical trials education at the University of California, San Francisco, Helen Diller Family Comprehensive Cancer Center, gives an overview of the development of PI3K and mTOR inhibitors for the treatment of breast cancer.

Right now in development, Rugo says, are TORC1/2 combination inhibitors, which have a fair amount of toxicity, alpha-specific PI3K inhibitors, and pan-PI3K inhibitors, which block both mTOR and PI3K. These agents are in all phases of development.

It will be interesting to see the effectiveness of these agents in various tumor subsets compared to their toxicities, Rugo says. Some toxicities of these agents do not overlap, so it remains possible to avoid troublesome toxicities of mTOR inhibitors while still gaining the benefits of pan-PI3K inhibitors.