Key clinical point: Several biomarkers were linked with the efficacy of palbociclib plus fulvestrant in patients with hormone receptor–positive, metastatic breast cancer.
Major finding: The efficacy of palbociclib was reduced with high levels of cyclin E1 mRNA expression compared with low levels (median PFS, 7.6 vs. 14.1 months; P = .00238).
Study details: A gene expression analysis of 302 patients with endocrine-pretreated metastatic breast cancer.
Disclosures: Pfizer supported the study. The authors reported financial interests with AbbVie, AstraZeneca, Genentech, Novartis, Pfizer, and others.
Turner NC et al. J Clin Oncol. 2019 Feb 26. doi: 10.1200/JCO.18.00925.