Health-Related Quality Of Life (Hrqol) Of Postmenopausal Women With Hormone Receptor-Positive (Hr Plus ), Human Epidermal Growth Factor Receptor 2-Negative (Her2-) Advanced Breast Cancer (Abc) Treated With Ribociclib Plus Letrozole: Results From Monaleesa-2.

1020Background: In the MONALEESA-2 trial, ribociclib + letrozole significantly improved progression-free survival (PFS) and showed higher overall response rates vs letrozole alone in HR+, HER2– ABC. To place these clinical results in the context of patient experience, here we present key patient-reported outcomes (PROs) including HRQoL. Methods: 668 patients were randomized (1:1); 334 each to the ribociclib + letrozole and placebo + letrozole arms. PROs were evaluated during treatment and at progression using the EORTC QLQ-C30, QLQ-BR23, and EQ-5D-5L questionnaires. Changes from baseline in all subscales were analyzed using a linear mixed-effect model and time to 10% deterioration was compared between treatment arms using the stratified log-rank test. Results: Questionnaire compliance rates were high (≥90%). During treatment, HRQoL (global health status/QoL score) was maintained and similar in both treatment arms. At progression/end of treatment, HRQoL worsened numerically in both arms. Time to definitive...