Stand up to cancer phase Ib study of pan-phosphoinositide-3-kinase inhibitor buparlisib with letrozole in estrogen receptor-positive/human epidermal growth factor receptor 2-negative metastatic breast cancer.

ABSTRACT:

Purpose

Buparlisib, an oral reversible inhibitor of all class I phosphoinositide-3-kinases, has shown antitumoral activity against estrogen receptor (ER)-positive breast cancer cell lines and xenografts, alone and with endocrine therapy. This phase Ib study evaluated buparlisib plus letrozole's safety, tolerability, and preliminary activity in patients with metastatic ER-positive breast cancer refractory to endocrine therapy.

Patients and methods

Patients received letrozole and buparlisib in two different administration schedules. Outcomes were assessed by standard solid-tumor phase I methods. [(18)F]fluorodeoxyglucose-positron emission tomography/computed tomography ([(18)F]FDG-PET/CT) scans were done at baseline and 2 weeks after treatment initiation. Tumor blocks were col

SUBMITTER: Mayer IA 

PROVIDER: S-EPMC3986383 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature