SABCS 2017: First-Line Ribociclib and Endocrine Therapy in Advanced Breast Cancer
By: Meg Barbor, MPH
Posted: Monday, December 11, 2017
The addition of the cyclin-dependent kinase (CDK) 4/6 inhibitor ribociclib to first-line endocrine therapy significantly improved progression-free survival in pre- and perimenopausal women with advanced hormone receptor–positive, HER2-negative breast cancer, with a manageable safety profile, according to data from the phase III MONALEESA-7 trial, presented by Debasish Tripathy, MD, of The University of Texas MD Anderson Cancer Center, Houston, and colleagues, at the 2017 San Antonio Breast Cancer Symposium (SABCS; Abstract GS2-05).
“MONALEESA-7 is the first clinical trial to have the statistical power to show that ribociclib has clinical benefit specifically for pre- and perimenopausal women with hormone receptor–positive, HER2-negative advanced breast cancer,” Dr. Tripathy reported. “It is also the first trial to show that ribociclib can be safely and effectively combined with either tamoxifen or a nonsteroidal aromatase inhibitor together with ovarian suppression using goserelin.”
A total of 672 patients who had received up to 1 line of chemotherapy and no prior endocrine therapy were randomized to treatment with either ribociclib in combination with tamoxifen or a nonsteroidal aromatase inhibitor (letrozole or anastrozole) and goserelin (n=335) or placebo in combination with the same oral hormonal therapy options and goserelin (n=337).
Median progression-free survival was significantly improved in the ribociclib arm: 23.8 months versus 13 months with placebo. The most frequent adverse event was neutropenia, reported in 76% of patients in the ribociclib arm compared with 8% in the placebo arm.