Palbociclib for the Treatment of Estrogen Receptor-Positive, HER2-Negative Metastatic Breast Cancer.

ABSTRACT: Palbociclib is a selective inhibitor of cyclin-dependent kinases 4 and 6 that acts by reducing phosphorylation of the tumor suppressor gene retinoblastoma. When added to the aromatase inhibitor letrozole in a randomized phase II trial for first-line therapy of estrogen receptor-positive, HER2-negative metastatic breast cancer, palbociclib significantly increased progression-free survival compared with letrozole alone [palbociclib + letrozole: 20.2 months; 95% confidence interval (CI), 13.8-27.5; letrozole: 10.2 months; 95% CI, 5.7-12.6; HR, 0.49; 95% CI, 0.32-0.75; P = 0.0004]. On the basis of these results, the drug was recently granted accelerated approval by the FDA, and confirmatory studies are ongoing. Because this drug has a rational target in an oncologic pathway, concurrent biomark

SUBMITTER: Morikawa A 

PROVIDER: S-EPMC4537809 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature