Demographic Characteristics and Treatment Patterns Among Patients Receiving Palbociclib for HR+/HER2- Advanced Breast Cancer: A Nationwide Real-World Experience

Onco Targets Ther. 2021 Jul 1:14:3971-3981. doi: 10.2147/OTT.S309862. eCollection 2021.

Abstract

Background: This nationwide retrospective study reports data on the real-world use of the selective cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitor palbociclib in a large population of advanced breast cancer (ABC) patients during a 2-year period in Hungary.

Methods: All patients with ABC who received palbociclib between May 1, 2017 and June 30, 2019 were included in the analysis. Patient demographic and clinical characteristics, disease-related factors and treatment patterns were examined during the early access program and in the regular reimbursement period.

Results: Altogether, 962 patients were included (mean age: 60.6 years). A total of 399 patients (41%) were treated with palbociclib plus aromatase inhibitors (P+AI), and 563 patients (59%) received palbociclib and fulvestrant (P+F). The most commonly prescribed AI was letrozole (n=359; 90%). Of those with metastatic disease (n=733; 76%), 241 patients (33%) had visceral metastases and 449 (61%) had bone-only disease. The majority of patients (79%) received palbociclib as first- or second-line therapy for ABC. The starting dose of palbociclib was 125 mg in 98% of patients; dose reductions were required in 32% of patients receiving P+AI and 31% of those treated with P+F. At the time of data collection, palbociclib therapy was ongoing in 270 patients (68%) in the P+AI group and 245 patients (44%) in the P+F group.

Conclusions: This nationwide analysis is the first to provide insights into the real-world use of palbociclib in a large patient population from a Central-Eastern European country. The findings confirm the good tolerability of palbociclib with similar dose reduction rates to those reported from registration trials.

Keywords: metastatic breast cancer; palbociclib; real-world; retrospective.

Grants and funding

This study was sponsored by Pfizer Ltd. Medical writing was provided by Syntesia Medical Communications Ltd., and was funded by Pfizer Ltd. Data collection was funded by Pfizer Ltd.