Treatment Patterns and Clinical Outcomes Among Patients Receiving Palbociclib Combinations for Hormone...

Palbociclib, a cyclin-dependent kinase 4/6 (CDK4/6) inhibitor, has been approved for advanced/metastatic breast cancer (ABC) treatment. However, real-world data on its use in the Arabian Gulf region are limited.

The TREASURE study, a retrospective, multicenter study, evaluated patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) ABC treated with palbociclib + endocrine therapy (ET) in the Arabian Gulf. Data were abstracted from the medical records of eligible patients from 7 selected sites across Arabian Gulf countries. The study evaluated patient demographics, clinical characteristics, treatment patterns, and clinical outcomes in those who initiated palbociclib + ET from April 2015 to September 2019.

The study comprised 258 patients (median age: 53.7 years) who received palbociclib in the first-line (1L) (n = 93, 36.0%), second-line (2L) (n = 61, 23.6%), or third-line and beyond (3L+) (n = 30, 11.6%). Treatment regimens included palbociclib plus aromatase inhibitors (n = 142, 55.0%) and palbociclib with fulvestrant (n = 120, 46.5%). The starting dose of palbociclib was 125 mg for 228 patients (88.4%). The median duration of follow-up was 16.8 months. Global median real-world progression-free survival (rwPFS) was 26.5 months (1L: 40.3, 2L: 18.5, 3L+: 17.2). The rwPFS rates at 12, 24, and 36 months were as follows: 1L-84.5%, 72.8%, and 58.4%; 2L-69.8%, 38.8%, and 16.2%; 3L+-80.0%, 42.3%, and 23.5%.

This study provides initial data on palbociclib's real-world treatment management and effectiveness in the Arabian Gulf region, with results consistent with those reported in clinical trials and other real-world evidence studies. Larger studies with more patients are needed to further assess long-term clinical outcomes in this population. Trial Registration: ClinicalTrials.gov identifier: NCT04916509.