Jonathan Wilkie1, M Alexandra Schickli2, Michael J Berger2, Maryam Lustberg3, Raquel Reinbolt3, Anne Noonan3, Bhuvaneswari Ramaswamy3, Sagar Sardesai3, Jeffrey VanDeusen3, Robert Wesolowski3, Nicole Williams3, Daniel G Stover3, Junan Li4, Craig A Vargo2. 1. Department of Pharmacy, The Stefanie Spielman Comprehensive Breast Center, The James Cancer Hospital and Solove Research Institute at The Ohio State University Wexner Medical Center, Columbus, OH. Electronic address: jonathan.wilkie@parkview.com. 2. Department of Pharmacy, The Stefanie Spielman Comprehensive Breast Center, The James Cancer Hospital and Solove Research Institute at The Ohio State University Wexner Medical Center, Columbus, OH. 3. Division of Medical Oncology, The Stefanie Spielman Comprehensive Breast Center, The James Cancer Hospital and Solove Research Institute at The Ohio State University Wexner Medical Center, Columbus, OH. 4. Division of Pharmacy Practice and Science, The Ohio State University College of Pharmacy, Columbus, OH.
Abstract
BACKGROUND: Additional use of cyclin-dependent kinase 4/6 inhibitors with endocrine therapy improves progression-free survival (PFS) in advanced hormone receptor (HR)-positive HER2-negative breast cancer. However, neutropenia is a common reason for dose reductions, leading to concerns about palbociclib efficacy at lower doses. A safety analysis confirmed no PFS differences between palbociclib doses in the second-line setting, but to our knowledge, this has not been evaluated for first-line treatment. PATIENTS AND METHODS: In this retrospective, single-center cohort study we evaluated real-world use of first-line palbociclib with aromatase inhibitor (AI) treatment in HR-positive, HER2-negative metastatic breast cancer patients who received treatment between February 2015 and July 2017. The primary objective was to determine PFS of treatment with palbociclib and an AI in a real-world first-line setting. Secondary objectives included determining the PFS for patients treated with palbociclib on the basis of final doses, time to first dose reduction, time to treatment failure (TTF), and safety. RESULTS: Seventy patients were included in the final analysis. Median PFS was 26.4 months. No significant differences in PFS were observed on the basis of final doses of palbociclib (P = .77). Time to first dose reduction was 2.3 months. Median TTF was 26.1 months. Dose delays, reductions, and Grade 3/4 neutropenia were common (63%, n = 44; 57%, n = 40; and 62%, n = 43, respectively). CONCLUSION: Real-world first-line palbociclib treatment produced outcomes similar to those in PALOMA-2 (Palbociclib and Letrozole in Advanced Breast Cancer) (median PFS 26.4 months vs. 24.8 months) despite more dose reductions (57%, n = 40 vs. 36%, n = 160) and shorter time to first dose reduction (2.3 vs. 3.0 months). No significant differences in PFS were observed for the varying palbociclib doses. Palbociclib dose reductions might not significantly affect PFS in the first-line setting.
BACKGROUND: Additional use of cyclin-dependent kinase 4/6 inhibitors with endocrine therapy improves progression-free survival (PFS) in advanced hormone receptor (HR)-positive HER2-negative breast cancer. However, neutropenia is a common reason for dose reductions, leading to concerns about palbociclib efficacy at lower doses. A safety analysis confirmed no PFS differences between palbociclib doses in the second-line setting, but to our knowledge, this has not been evaluated for first-line treatment. PATIENTS AND METHODS: In this retrospective, single-center cohort study we evaluated real-world use of first-line palbociclib with aromatase inhibitor (AI) treatment in HR-positive, HER2-negative metastatic breast cancerpatients who received treatment between February 2015 and July 2017. The primary objective was to determine PFS of treatment with palbociclib and an AI in a real-world first-line setting. Secondary objectives included determining the PFS for patients treated with palbociclib on the basis of final doses, time to first dose reduction, time to treatment failure (TTF), and safety. RESULTS: Seventy patients were included in the final analysis. Median PFS was 26.4 months. No significant differences in PFS were observed on the basis of final doses of palbociclib (P = .77). Time to first dose reduction was 2.3 months. Median TTF was 26.1 months. Dose delays, reductions, and Grade 3/4 neutropenia were common (63%, n = 44; 57%, n = 40; and 62%, n = 43, respectively). CONCLUSION: Real-world first-line palbociclib treatment produced outcomes similar to those in PALOMA-2 (Palbociclib and Letrozole in Advanced Breast Cancer) (median PFS 26.4 months vs. 24.8 months) despite more dose reductions (57%, n = 40 vs. 36%, n = 160) and shorter time to first dose reduction (2.3 vs. 3.0 months). No significant differences in PFS were observed for the varying palbociclib doses. Palbociclib dose reductions might not significantly affect PFS in the first-line setting.
Authors: Kristoffer B Kristensen; Ida Marie Nedergaard Thomsen; Tobias Berg; Annette R Kodahl; Anders Bonde Jensen Journal: Breast Cancer Res Treat Date: 2021-04-10 Impact factor: 4.872
Authors: Claire C Conley; McKenzie McIntyre; Nicole A Pensak; Filipa Lynce; Deena Graham; Roohi Ismail-Khan; Katherine Lopez; Susan T Vadaparampil; Suzanne C O'Neill Journal: Breast Cancer Res Treat Date: 2022-01-07 Impact factor: 4.872