A Phase Ib/II, Multicenter Study of the Combination of LEE011 and BYL719 with Letrozole in Adult Patients with Advanced ER+ Breast Cancer

Sponsor: Novartis Oncology

Location(s): United States


The purpose of this trial is to inform the future clinical development of the two investigational agents in ER+ breast cancer, LEE011 (CDK4/6 inhibitor) and BYL719 (PI3K-alpha inhibitor).

This is a multi-center, open-label Phase Ib/II study. The Phase Ib portion of the study is a dose escalation to estimate the MTD and/or RP2D for three regimens: two double combinations, LEE011 with letrozole and BYL719 with letrozole, followed by the triple combination of LEE011 + BYL719 with letrozole.

The Phase Ib will be followed by a randomized Phase II study to assess the preliminary anti-tumor activity of the two double combination regimens (LEE011+letrozole and BYL719+letrozole) versus the triple combination (LEE011+BYL719 with letrozole) and to further evaluate their safety in patients with ER+/HER2- locally advanced or metastatic breast cancer.

Approximately 300 adult women with ER+/HER2- locally advanced or metastatic breast cancer will be enrolled.