This article is more than 5 years old. Information may no longer be current.
FDA approves Ibrance for advanced breast cancer
Click Here to Manage Email Alerts
The FDA today granted accelerated approval to Ibrance for the treatment of postmenopausal women with ER-positive, HER-2–negative metastatic breast cancer.
Ibrance (palbociclib, Pfizer) — which inhibits cyclin-dependent kinases 4 and 6 — is intended to be used in combination with Femara (letrozole, Novartis) in women who have not previously received endocrine-based therapy.
“The addition of palbociclib to letrozole provides a novel treatment option to women diagnosed with metastatic breast cancer,” Richard Pazdur, MD, director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research, said in a press release. “The FDA is committed to expediting marketing approval of cancer drugs through our accelerated approval regulations.”
The FDA based the approval in part on results of a phase 2 study that included 165 postmenopausal women with ER-positive, HER-2–negative advanced breast cancer. Researchers assigned patients to Femara with or without Ibrance.
Patients who received the combination achieved a median PFS of 20.2 months, nearly double the 10.2 month-median PFS demonstrated by patients assigned Femara alone. Ibrance plus Femara was associated with a 51% reduction in the risk for disease progression compared with Femara alone.
Common side effects associated with Ibrance included neutropenia, leukopenia, fatigue, anemia, upper respiratory infection, nausea, stomatitis, alopecia, diarrhea, thrombocytopenia, decreased appetite, vomiting, asthenia, peripheral neuropathy and epistaxis.
“With the FDA approval, this study represents a potential practice-changing result,” Dennis Slamon, MD, PhD, director of the Revlon/UCLA Women’s Cancer Research Program and Clinical/Translational Research at Jonsson Comprehensive Cancer Center, where the Ibrance study was conducted, said in a press release. “I believe [Ibrance] will now become a standard treatment approach for postmenopausal women with ER-positive/HER-2–negative metastatic breast cancer.”
Perspective
Back to Top
Douglas Yee, MD
The approval of palbociclib for the treatment of ER-positive, HER-2–negative breast cancer represents an advance for several reasons. First, this approval provides additional evidence that inhibition of estrogen receptor function can be inhibited by blocking signaling molecules other than the estrogen receptor. We now have two choices, mTOR inhibition with everolimus (Afinitor, Novartis) and CDK4/6 inhibition with palbociclib.Second, the data that led to the approval of palbociclib came from a randomized phase 2 trial first presented at the San Antonio Breast Cancer Symposium in December 2012. Final results were presented at the AACR Annual Meeting in 2014. Approval was based on a small number of patients (n = 165) who showed an improvement in PFS but not OS. The availability of palbociclib demonstrates that the FDA is willing to expedite drug approval for new therapies with exceptional results, even when data are obtained from relatively small clinical trials.
Further studies involving additional palbociclib combinations in advanced- and early-stage breast cancer are ongoing. This approval of palbociclib give us additional tools to treat ER-positive breast cancer and should further development of new signaling inhibitor drugs.
Click Here to Manage Email Alerts