ESMO 2019: Survival Benefit Reported With CDK4/6 Inhibitor in Advanced Breast Cancer
Posted: Monday, October 14, 2019
The results of the MONALEESA-3 trial, presented at the 2019 European Society for Medical Oncology (ESMO) Congress in Barcelona (Abstract LBA7_PR), indicate that for patients with postenopausal hormone receptor–positive and HER2-negative advanced breast cancer, first- and second-line therapies with ribociclib plus fulvestrant “significantly improved” overall survival. Dennis J. Slamon, MD, PhD, of the Jonsson Comprehensive Cancer Center at the University of California, Los Angeles, and colleagues found that the cyclin-dependent kinase 4/6 (CDK4/6) inhibitor with endocrine therapy benefits those patients not previously treated with hormonal therapy and women who had become resistant to endocrine therapy.
“This is a significant, practice-changing report,” Dr. Slamon said in an ESMO press release. “The data from MONALEESA-3 clearly show that if postmenopausal patients receive [ribociclib plus fulvestrant] right up front, there is a very significant benefit … in overall survival—which is the hardest endpoint to reach and the most important one in terms of making an impact on the disease.”
In this phase III study, the authors enrolled 726 patients who were postmenopausal and diagnosed with hormone receptor–positive and HER2-negative advanced breast cancer. The patients received either ribociclib plus fulvestrant or placebo plus fulvestrant as first- and second-line therapies.
After a median follow-up of 39.4 months, patients treated with ribociclib plus fulvestrant demonstrated a statistically significant overall survival prolongation compared with those treated with placebo (not reached vs. 40.0 months, respectively). These benefits were consistent across all subgroups of patients, including in the first-line setting (not reached vs. 45.1 months) and in the early relapse/second-line setting (40.2 months vs. 32.5 months). For patients receiving first-line treatment, the median progression-free survival in those women treated with ribociclib plus fulvestrant was 33.6 months, versus 19.2 months for those in the placebo cohort.
Disclosure: The study authors’ disclosure information may be found at cslide.ctimeetingtech.com.