Novartis today announced updated median overall survival (OS) results for ribociclib in combination with fulvestrant in the first-line subgroup of postmenopausal women with hormone receptor-positive, human epidermal growth factor receptor-2 negative (HR+/HER2-) advanced or metastatic breast cancer.

The analysis of patients treated in first-line with ribociclib plus fulvestrant demonstrated a significant OS benefit of nearly 16 months compared to those treated with fulvestrant alone. This updated exploratory OS analysis from the Phase III MONALEESA-3 study will be presented as a late-breaker mini-oral presentation at the 2022 European Society of Medical Oncology (ESMO) Breast Cancer Congress.

“MONALEESA-3 results continue to demonstrate the survival benefit of treatment with ribociclib for postmenopausal women with advanced breast cancer,” said Dennis J. Slamon, MD, Director of Clinical/Translational Research, University of California, Los Angeles Jonsson Comprehensive Cancer Center.

“Whether partnered with fulvestrant or an aromatase inhibitor in the first-line setting, ribociclib offers oncologists a CDK4/6 inhibitor with consistent benefit in providing women with HR+/HER2- advanced breast cancer more quality time, regardless of their disease characteristics.”

In this MONALEESA-3 exploratory analysis, patients were further evaluated for a median of 71 months, more than two-and-a-half years of additional follow-up since the final key secondary endpoint OS analysis, which was presented at ESMO Congress 2019 and published in the New England Journal of Medicine. 

The final OS analysis demonstrated a statistically significant OS benefit for Kisqali in combination with fulvestrant and a relative reduction in the risk of death by 28% compared to fulvestrant alone in the full population (HR=0.72; 95% CI: 0.568-0.924; p=0.00455)1,5-6.

This new updated analysis with a median follow-up of five years found that in the first-line setting, Kisqali plus fulvestrant (n=237) achieved 67.6 months median OS as compared to 51.8 months for those treated with fulvestrant alone (n=128) (HR=0.673; 95% CI: 0.504-0.899). Patients treated with Kisqali plus fulvestrant compared to those on fulvestrant alone in the first-line setting experienced over one-and-a-half years of additional delay to subsequent use of chemotherapy (49.2 months versus 29.0 months, respectively; HR=0.624; 95% CI: 0.481-0.810).

With this extended follow-up, the estimated survival rate at five years was 56.5% (95% CI: 49.5-62.9) for women who received Kisqali in combination with fulvestrant in first-line compared to 42.1% (95% CI: 33.2-50.7) for women who received fulvestrant alone.

Additionally, 16.5% of patients in the Kisqali plus fulvestrant arm (n=39) compared to 8.6% of those in the fulvestrant only arm (n=11) were still ongoing on therapy at this longer follow-up. No new adverse events were observed.

“It is a tremendous achievement to see such remarkable, consistent overall survival results from the MONALEESA clinical trial program, demonstrating how Novartis is transforming care for people with breast cancer as we continue to work toward cures,” said Jeff Legos, Executive Vice President, Global Head of Oncology & Hematology Development.

“The unique profile of Kisqali continues to be reinforced, with results from MONALEESA-3 pushing the boundaries of how using a Kisqali-combination treatment regimen can extend lives of postmenopausal women living with HR+/HER2- advanced breast cancer without compromising quality of life.”

Source: Massachusetts General Hospital