MONALEESA-7 Update: Ribociclib Plus Endocrine Therapy for Advanced Breast Cancer
Posted: Thursday, February 11, 2021
Debu Tripathy, MD, of The University of Texas MD Anderson Cancer Center, Houston, and colleagues reported that the CDK4/6 inhibitor ribociclib plus endocrine therapy demonstrated a “clinically relevant” overall survival benefit compared with endocrine therapy alone in women with hormone receptor–positive, HER2-negative advanced breast cancer. Their findings, which represent an extended follow-up of more than 4 years from the phase III MONALEESA-7 trial, were presented at the 2020 San Antonio Breast Cancer Symposium (Abstract PD2-04).
Pre- or postmenopausal individuals with this type of breast cancer were enrolled in this study. Patients had up to one prior line of chemotherapy in the neoadjuvant or adjuvant setting. Participants were randomly assigned 1:1 to receive ribociclib or a placebo plus goserelin (intent-to-treat group) and either tamoxifen or a nonsteroidal aromatase inhibitor.
The median follow-up was 53.5 months. Compared with the placebo arm, the ribociclib arm of the intent-to-treat group demonstrated a higher median overall survival benefit (48 months vs. 58.7 months). A comparable result occurred in the patients who received a nonsteroidal aromatase inhibitor, with median overall survivals of 58.7 months and 47.7 months with ribociclib and placebo plus nonsteroidal aromatase inhibitor, respectively.
In the intent-to-treat population, median progression-free survival 2, time to chemotherapy, and chemotherapy-free survival were 44.2 and 31.0 months, 50.9 and 36.8 months, and 42.4 and 26.4 months for the ribociclib and placebo groups, respectively. For the nonsteroidal aromatase inhibitor group, the results were 43.6 and 30.4 months, 50.9 and 36.0 months, 42.5 and 25.9 months for the ribociclib and placebo groups, respectively. Subsequent antineoplastic therapy was administered to 77.3% of patients in the intent-to-treat ribociclib group and 78.1% of placebo patients who discontinued study treatment. A subsequent line of a CDK4/6 inhibitor was given to the remaining patients who halted therapy.
Disclosure: For full disclosures of the study authors, visit sabcs.org.