Pfizer Inc has announced that the phase III PALOMA-3 trial comparing the efficacy of Ibrance (palbociclib) plus fulvestrant with fulvestrant plus placebo met its primary endpoint of demonstrating an improvement in progression-free survival in women with hormone receptor positive (HR+), human epidermal growth factor receptor 2 negative (HER2-) metastatic breast cancer who had experienced disease progression on or after endocrine therapy.
In the trial, 521 patients from 150 global sites were randomly assigned 2:1 to receive Ibrance 125mg once daily for 21 days of each 28-day cycle plus fulvestrant 500mg IM on days 1 and 15 of cycle 1, and then on day 1 for each subsequent cycle, or fulvestrant plus placebo.
Researchers stopped the study early due to efficacy based on an independent Data Monitoring Committee assessment.
“The results of this trial are especially important because they help us understand the potential of IBRANCE to improve outcomes in patients with this difficult to treat cancer. We’re gratified to be able to stop the trial early and are engaging in discussions with health authorities regarding a regulatory path forward,” said Dr. Mace Rothenberg, senior vice president of Clinical Development and Medical Affairs and chief medical officer for Pfizer Oncology.
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In regard to safety, adverse events reported with Ibrance plus fulvestrant were mostly consistent with their known safety profiles
Pfizer plans to report detailed efficacy and safety results from PALOMA-3 at the American Society of Clinical Oncology (ASCO) 2015 Annual Meeting later this year in Chicago, Illinois.
- Pfizer announces PALOMA-3 trial for Ibrance (palbociclib) stopped early due to efficacy seen in patients with HR+, HER2- metastatic breast cancer whose disease has progressed following endocrine therapy [news release]. New York, NY: Pfizer Inc; April 15, 2015. http://www.pfizer.com/news/press-release/press-release-detail/pfizer_announces_paloma_3_trial_for_ibrance_palbociclib_stopped_early_due_to_efficacy_seen_in_patients_with_hr_her2_metastatic_breast_cancer_whose_disease_has_progressed_following_endocrine_therapy. Accessed April 16, 2015.