Palbociclib, an investigational oral medication that works by blocking molecules responsible for cancer cell growth, is well tolerated and extends progression-free survival (PFS) in newly diagnosed, advanced breast cancer patients, including those whose disease has stopped responding to traditional endocrine treatments. Results of the phase II study, led by researchers in the Abramson Cancer Center and the Perelman School of Medicine at the University of Pennsylvania, were published this month in Clinical Cancer Research. Earlier phase I results by researchers at Penn Medicine contributed to the development of palbociclib, which was recently approved by the U.S. Food and Drug Administration (FDA) for metastatic breast cancer patients just beginning to undergo endocrine therapy.
"The FDA approval has expanded treatments options for many metastatic breast cancer patients, but these new results are showing how effective the drug can also be for breast cancer patients who have already tried endocrine therapies and may be running out of options," said lead investigator Angela DeMichele, MD, MSCE , associate professor in the division of Hematology/Oncology and Epidemiology and co-leader of the Breast Cancer Research Program at the Abramson Cancer Center. "Combined with the promising results from other trials looking at the effectiveness of this drug, our results indicate that palbociclib can extend the duration of disease control and produce tumor shrinkage in patients with estrogen-receptor positive (ER+) breast cancer, without the debilitating side effects of chemotherapy."
Other Penn authors on the study include Kay See Tan, Daniel Heitjan, PhD, Kristi Gramlich, Maryann Gallagher, Priti Lal, MD, Michael Feldman, MD, Paul Zhang, MD, Christopher Colameco, David Lewis, Melissa Langer, Noah Goodman, Susan Domchek, MD, Keerthi Gogineni, MD, Mark Rosen, MD, and Kevin Fox, MD.
