Summary

The purpose of this study is determine if the triplet combination of ribociclib, everolimus
and exemastane is safe and effective in the treatment of locally advanced/metastatic breast
cancer following treatment with a CDK 4/6 inhibitor

Objectives

This trial had two phases. The purpose of Phase I dose escalation and dose de-escalation was
to determine the maximum tolerated doses (MTDs) and/or identify the recommended Phase II dose
(RP2D) of the combination treatment of ribociclib+ everolimus + exemestane. The dosing was
continuous in adult men and postmenopausal women with HR+ HER2-negative advanced breast
cancer which was resistant to the non-steroidal aromatase inhibitors, fulvestrant or
tamoxifen.

The purpose of the phase II portion of this trial was to evaluate the anti-tumor activity of
exemestane, everolimus and ribociclib combination therapy following progression on a CDK 4/6
inhibitor.

The planned duration of the study was 30 months.