Health-Related Quality of Life in Patients with HR+/HER2- Early Breast Cancer Treated with Ribociclib Plus a Nonsteroidal Aromatase Inhibitor: Results from the NATALEE Trial.

Purpose: The phase III NATALEE trial reported a statistically significant invasive disease-free survival benefit with ribociclib plus nonsteroidal aromatase inhibitor (NSAI) versus an NSAI alone in stage II/III hormone receptor-positive, HER2-negative (HR+/HER2-) early breast cancer. In this study, we report health-related quality of life (HRQOL) data from NATALEE.

Patients And Methods: Patients were randomized to receive ribociclib plus NSAI or NSAI alone. Patient-reported outcome scores [European Organisation for Research and Treatment of Cancer core quality of life questionnaire global health status and physical, social, and emotional functioning domains; the supplementary European Organisation for Research and Treatment of Cancer breast cancer-specific QOL questionnaire breast symptoms scale; health on a visual analog scale of the generic EuroQOL 5-level instrument; and the Hospital Anxiety and Depression Scale] were assessed. The prespecified primary HRQOL endpoint was physical functioning. Mean scores and time-categorical and prespecified linear-time repeated-measure models were used to evaluate HRQOL changes during treatment.

Results: HRQOL was evaluated in all patients in the ribociclib plus NSAI (n = 2,549) and NSAI alone (n = 2,552) arms. Compliance was high in both arms (≈93%-97%). Mean scores did not differ meaningfully from baseline for any analyzed domain. Likewise, neither a meaningful change from baseline (in either treatment arm) nor a difference between arms was observed during treatment in the time-categorical, model-adjusted mean scores for any HRQOL domains-using published thresholds for interpreting longitudinal and between-group differences, with all values being within 0.5 SD of their baseline values. Linear-time regression analysis confirmed these findings.

Conclusions: These analyses of NATALEE show that adding adjuvant ribociclib to an NSAI does not negatively affect HRQOL in patients with HR+/HER2- early breast cancer.