Promising drug doubled positive effect in hormone-receptor positive breast cancer, study finds
An investigational drug discovered and being developed by Pfizer Inc., palbociclib targets a key family of proteins (CDK4/6) responsible for cell growth by preventing them from dividing. Results of the multi-year phase 2 study showed a significant increase in PFS for patients with advanced breast cancer that was estrogen receptor positive (ER+), HER2-negative (HER2-), who were given a combination of the standard anti-estrogen treatment, letrozole, and palbociclib compared to letrozole alone. “We’re essentially putting the brakes on cell proliferation and causing these tumor cells to stop growing,” said Dr. …