Continuous versus Standard Palbociclib Treatment and Molecular Profiling of Solid Tissues and Liquid Biopsies in the CCTG MA.38 Trial in Advanced Breast Cancer.

ABSTRACT: The randomized phase II MA.38 trial estimated the relative progression-free survival (PFS) associated with second-line endocrine therapy plus palbociclib administered on a 100 mg continuous daily dosing (CDD) schedule compared with the standard dose schedule (SDS) of 125 mg (days 1-21 of a 28-day cycle). A total of 180 patients were allocated 1:1 to protocol therapy. Molecular profiling was performed on the archival tissue and cell-free DNA (cfDNA) at enrollment, 3 months, and 6 months. The primary analysis for PFS demonstrated a similar outcome for the CDD versus SDS treatment strategy: HR = 0.93 (90% confidence interval, 0.66-1.30). Secondary efficacy measures for CDD versus SDS included the following: overall survival, HR = 1.07 (90% confidence interval, 0.67-1.69); response rate, 16.1%

SUBMITTER: Joy AA 

PROVIDER: S-EPMC12613153 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature