Real-world palbociclib effectiveness in patients with metastatic breast cancer: Focus on neutropenia-related treatment modification strategies and clinical outcomes.

Autor: Hackert MQN; Santeon hospital group, Utrecht, The Netherlands., van Uden-Kraan CF; Santeon hospital group, Utrecht, The Netherlands., Agterof MJ; Department of Internal Medicine, St. Antonius Hospital, Utrecht/Nieuwegein, The Netherlands., van der Velden AWG; Department of Internal Medicine, Martini Hospital, Groningen, The Netherlands., Vriens BEPJ; Department of Medical Oncology, Catharina Hospital, Eindhoven, The Netherlands., Janssen JJB; Department of Medical Oncology, Canisius Wilhelmina Hospital, Nijmegen, The Netherlands., Geenen M; Department of Medical Oncology, OLVG, Amsterdam, The Netherlands., van der Padt-Pruijsten A; Department of Internal Medicine, Maasstad Hospital, Rotterdam, The Netherlands., van de Garde EMW; Department of Clinical Pharmacy, St. Antonius Hospital, Utrecht/Nieuwegein, The Netherlands; Division of Pharmacoepidemiology and Clinical Pharmacology, Department of Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands. Electronic address: e.van.de.garde@antoniusziekenhuis.nl.
Jazyk: angličtina
Zdroj: Cancer treatment and research communications [Cancer Treat Res Commun] 2023; Vol. 35, pp. 100691. Date of Electronic Publication: 2023 Feb 14.
DOI: 10.1016/j.ctarc.2023.100691
Abstrakt: Introduction: In addition to clinical trials, real-world data is needed to verify the effectiveness of the CDK 4/6 inhibitor palbociclib. The primary aim was to examine real-world variation in treatment modification strategies for neutropenia and its relation to progression-free survival (PFS). The secondary aim was to assess if there is a gap between real-world and clinical trial outcomes.
Materials and Methods: In this multicenter, retrospective observational cohort study 229 patients were analyzed who started palbociclib and fulvestrant as second- or later-line therapy for HR-positive, HER2-negative metastatic breast cancer in the Santeon hospital group in the Netherlands between September 2016 and December 2019. Data were manually retrieved from patients' electronic medical records. PFS was examined using the Kaplan-Meier method to compare neutropenia-related treatment modification strategies within the first three months after neutropenia grade 3 - 4 occurred, as well as patients' eligibility to have participated in the PALOMA-3 clinical trial or not.
Results: Even though treatment modification strategies differed from those in PALOMA-3 (dose interruptions: 26 vs 54%, cycle delays: 54 vs 36%, and dose reductions: 39 vs 34%), these did not influence PFS. Patients who were PALOMA-3 ineligible experienced a shorter median PFS than those who were eligible (10.2 vs. 14.1 months; HR 1.52; 95% CI 1.12 - 2.07). An overall longer median PFS was found compared to PALOMA-3 (11.6 vs. 9.5 months; HR 0.70; 95% CI 0.54 - 0.90).
Conclusion: This study suggests no impact of neutropenia-related treatment modifications on PFS and confirms inferior outcomes outside clinical trial eligibility.
(Copyright © 2023. Published by Elsevier Ltd.)
Databáze: MEDLINE
Externí odkaz: