Comparative real-world Progression Free Survival of CDK4/6 Inhibitors in HR+/HER2- Breast Cancer Patients with Bone Metastases
Menée à partir de données portant sur 1 399 patientes atteintes d'un cancer du sein HR+ HER2- avec métastatases osseuses, cette étude multicentrique rétrospective compare l'efficacité, du point de vue de la survie sans progression dans un contexte de vie réelle, et la toxicité de différents inhibiteurs de CDK4/6 (abémaciclib, ribociclib et palbociclib) en combinaison avec un traitement endocrinien
BACKGROUND: The introduction of CDK4/6 inhibitors (CDK4/6i) has improved outcomes in hormone receptor-positive (HR+)/HER2-negative metastatic breast cancer (mBC), including in patients with bone metastases. Assessing their comparative effectiveness in real-world settings is crucial.
METHOD: This retrospective, multicenter cohort study (January 2019–December 2023; median follow-up 39 months) evaluated the real-world progression-free survival (rwPFS) of abemaciclib, ribociclib, and palbociclib combined with endocrine therapy (ET) in HR+/HER2- mBC patients with bone metastases. Overall survival (OS) was a secondary exploratory endpoint. A total of 1399 patients with ECOG PS 0–1 and at least 12 months of follow-up were included. Analyses used propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) to adjust for confounding.
RESULTS: Palbociclib showed shorter rwPFS (22 months) compared to abemaciclib (32 months; HR = 1.47, p = 0.001) and ribociclib (35 months; HR = 1.49, p < 0.001). No significant difference was observed between abemaciclib and ribociclib. OS was also lower with palbociclib (47 months) versus abemaciclib (60 months; HR = 1.77, p < 0.001) and ribociclib (64 months; HR = 1.69, p = 0.001). Results were consistent after PSM and IPTW adjustment.
CONCLUSION: Ribociclib and abemaciclib may provide superior rwPFS and OS compared to palbociclib in HR+/HER2- mBC patients with bone metastases.
The Oncologist , résumé, 2026