MONALEESA-7 trial demonstrates significant outcomes in breast cancer

Phase III clinical trial data presented this week at the 2017 San Antonio Breast Cancer Symposium, Texas has shown that adding the CDK4/6 inhibitor ribociclib (Kisqali) to standard endocrine therapy with temporary ovarian suppression significantly improved progression-free survival for pre- and perimenopausal women with advanced hormone receptor–positive (HR-positive), HER2-negative breast cancer. The MONALEESA-7 phase III clinical trial was led by Doctor Debu Tripathy and focused on pre- and perimenopausal women with HR-positive, HER2- negative advanced breast cancer. Professor of medicine and chair of the Department of Breast Medical Oncology at The University of Texas MD Anderson Cancer Center in Houston, Dr Tripathy explained how the trial was among the first of its kind: MONALEESA-7 is the first clinical trial to have the statistical power to show that ribociclib has clinical benefit and can be safely and effectively combined with either tamoxifen or a nonsteroidal aromatase inhibitor together with ovarian suppression using goserelin.  Doctor Debu Tripathy Details of the MONALEESA-7 trial disclosed the extent of the study which looked at over 600 patients, with half randomized to ribociclib in combination with either tamoxifen or a nonsteroidal aromatase inhibitor (letrozole or anastrozole) and goserelin, and half randomized to placebo in combination with the same oral hormonal therapy options and goserelin. The trial achieved success meeting its primary endpoint of progression-free survival - the results showing significant improvement in the ribociclib arm compared with the placebo arm. Three anticancer therapeutics that target cell-cycle mediators CDK4 and CDK6, so-called CDK4/6 inhibitors, have been approved by the U.S. Food and Drug Administration for use in combination with hormonal drugs, either aromatase inhibitors or fulvestrant, for treating postmenopausal women with HR-positive, HER2-negative advanced breast cancer. These new therapeutics have not yet been evaluated in a dedicated large, randomized trial as a potential treatment for the 30 to 40 percent of women with HR-positive, HER2-negative advanced breast cancer who are pre- or perimenopausal. Median progression-free survival was 23.8 months in the ribociclib arm compared with 13.0 months in the placebo arm. Data are available for some of the secondary endpoints. Longer follow-up is needed to determine whether the trial will meet its secondary endpoint of overall survival. However, these initial results are very exciting because the World Health Organization reports that breast cancer is the leading cause of cancer-related death among women aged 20–59 years worldwide.Doctor Debu Tripathy This study was supported by funds from Novartis. Tripathy serves as a paid consultant for Novartis. The University of Texas MD Anderson Cancer Center received funds from Novartis to conduct this study. About SABCS: The mission of the 2017 San Antonio Breast Cancer Symposium is to produce a unique and comprehensive scientific meeting that encompasses the full spectrum of breast cancer research, facilitating the rapid translation of new knowledge into better care for patients with breast cancer. The UT Health San Antonio Cancer Center, the American Association for Cancer Research (AACR), and Baylor College of Medicine are joint sponsors of the San Antonio Breast Cancer Symposium. This collaboration utilizes the clinical strengths of the UT Health San Antonio Cancer Center and Baylor and the AACR’s scientific prestige in basic, translational, and clinical cancer research to expedite the delivery of the latest scientific advances to the clinic. For more information about the symposium, please visit www.sabcs.org