The goal of this study was to reverse the resistance to endocrine therapy and delay time to chemotherapy, explained Fabrice Andre, MD, Institut Gustave Roissy, Villejuif, France. “The control group is appropriate because we have no better endocrine therapy than exemestane. Progression-free survival is a good endpoint, and there is no major bias in this trial to influence results.”

This is the third trial to consistently report the benefits of everolimus plus hormonal therapy in improving progression-free survival, he continued. “The hazard ratio for everolimus is consistent with that of other major molecular targeted agents, including gefitinib, imatinib, trastuzumab, and sunitinib,” he noted.

“These findings show that the first-in-class targeted agent is highly effective. Everolimus not only improves outcomes [in patients with hormone-refractory metastatic breast cancer] but also open the door to study this drug in combination with other drugs to avoid resistance that develops via compensatory pathways once mTOR is inhibited. It will require sequential biopsies to understand and reverse mechanisms of resistance,” he told listeners. ■