KEY TAKEAWAYS
- The MONALEESA-3 phase III trial aimed to investigate the long-term OS benefits of ribociclib plus fulvestrant in the initial treatment of HR+/HER2− advanced breast cancer in postmenopausal women.
- PFS2 and CFS were analyzed.
- The study found that Ribociclib plus fulvestrant improves long-term OS in HR+/HER2− advanced breast cancer postmenopausal women, supporting its use as first-line therapy.
Ribociclib plus fulvestrant is now a preferred first-line HR+/HER2− advanced breast cancer treatment.
Researchers aimed to investigate the long-term overall survival(OS) benefits of ribociclib plus fulvestrant in the initial treatment of HR+/HER2− advanced breast cancer in postmenopausal women.
Postmenopausal patients(pts) with HR+/HER2- advanced breast cancer (ABC) were randomly assigned in a 2:1 ratio to receive either first-line (1L) or second-line (2L) fulvestrant plus ribociclib or a placebo. OS in 1L pts(de novo disease or relapse > 12 months from completion of [neo]adjuvant ET) was evaluated using statistical methods. The study also examined progression-free survival 2 (PFS2) and chemotherapy-free survival (CFS).
The outcome demonstrated that in a median follow-up of 70.8 months, the median overall survival (mOS) was 67.6 months for 1L ribociclib treatment, compared to 51.8 months for the placebo, with (hazard ratio (HR) 0.67; 95% CI 0.50–0.90). At that time, 16.5% of ribociclib patients and 8.6% of placebo patients were still receiving treatment. Progression-free survival (PFS2) and clinical benefit (CFS) also favored ribociclib, with HRs of (0.64) and (0.62), respectively. Among those who discontinued treatment, 16.7% on ribociclib and 35.0% on placebo received a subsequent CDK4/6 inhibitor. No new safety concerns were identified.
The study found that ribociclib plus fulvestrant improves long-term OS in HR+/HER2− advanced breast cancer postmenopausal women, supporting its use as first-line therapy.
Source: https://breast-cancer-research.biomedcentral.com/articles/10.1186/s13058-023-01701-9
Clinical Trial: https://clinicaltrials.gov/study/NCT02422615
Neven, P., Fasching, P.A., Chia, S. et al. Updated overall survival from the MONALEESA-3 trial in postmenopausal women with HR+/HER2− advanced breast cancer receiving first-line ribociclib plus fulvestrant. Breast Cancer Res 25, 103 (2023). https://doi.org/10.1186/s13058-023-01701-9
