The combination of ribociclib and endocrine therapy demonstrates consistent efficacy and a manageable safety profile across different age groups in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer. This conclusion stems from pooled analyses of the MONALEESA-2, -3, and -7 trials presented at the 2023 San Antonio Breast Cancer Symposium (SABCS). These findings offer valuable insights into treatment options for elderly patients with this prevalent cancer type.
Previous data from the MONALEESA trials have established the efficacy of ribociclib plus endocrine therapy in improving progression-free survival (PFS) and overall survival (OS) in this patient population. This new analysis specifically focuses on evaluating efficacy, safety, and quality of life (QOL) outcomes in elderly patients, addressing critical questions regarding age-related comorbidities and potential treatment toxicities.
Age-Specific Analysis of Ribociclib Benefits
The pooled analysis included 1229 patients across the three trials, categorized into three age groups: younger than 65 years (773 patients), 65 to 74 years (335 patients), and 75 years and older (121 patients). While minor baseline characteristic differences were observed, such as a higher percentage of fragile patients in the oldest group and more de novo metastatic disease in the youngest group, the core findings remained consistent across all ages.
Figure 1: Graphical representation of the efficacy and safety data of ribociclib plus endocrine therapy across different age groups in patients with HR+, HER2- advanced breast cancer.
Remarkably, the benefits in PFS and OS with ribociclib plus endocrine therapy compared to the control arm (placebo plus endocrine therapy) were observed regardless of age. Furthermore, the combination therapy significantly delayed the median time to first chemotherapy (TTC) in all age groups, suggesting a prolonged period of benefit from the initial treatment strategy.
Safety and Tolerability in Elderly Patients
Safety data in the under-65 group aligned with the overall trial population. In the older groups (65 to 74 years and 75 years and older), the most frequent adverse events (AEs) were neutropenia, nausea, fatigue, and diarrhea—common side effects associated with this type of treatment. While rates of grade 3/4 febrile neutropenia, interstitial lung disease, and QT prolongation were numerically higher in the older groups compared to the younger group, the overall safety profile remained consistent with what is expected in an older patient population. Importantly, there was no difference in time to definitive deterioration (TTD) in global health status between the ribociclib and control arms in patients aged 65 and older.
Optimizing Treatment Strategies for Elderly Patients
The study highlights the potential to optimize AE management in elderly patients through dose adjustments without necessarily discontinuing treatment. This approach, supported by other research indicating maintained survival benefits with reduced doses, offers a personalized treatment strategy that balances efficacy and tolerability.
Conclusion: A Promising Treatment Option for Elderly Patients
These pooled analyses from the MONALEESA trials confirm that ribociclib plus endocrine therapy provides consistent PFS and OS benefits in elderly patients with HR+, HER2- advanced breast cancer, comparable to those observed in younger patients. The therapy also delays the need for subsequent chemotherapy across all age groups. While the safety profile requires careful monitoring, especially for specific AEs, it remains manageable and consistent with expectations for older patients. For personalized treatment plans, consult with a healthcare professional to discuss the potential benefits and risks of ribociclib plus endocrine therapy.
Reference
Hart L. Efficacy, safety, and quality of life with ribociclib plus endocrine therapy in elderly patients with hormone receptor-positive, HER2-negative advanced breast cancer across the MONALEESA-2, -3, and -7 trials. Presented at: San Antonio Breast Cancer Symposium. December 5-9, 2023.
