A Real-world Study of Everolimus Plus Aromatase Inhibitor in Hormone Receptor-positive, HER2-negative Advanced Breast Cancer.

Abstract

Everolimus in combination with exemestane was shown to offer benefit versus exemestane monotherapy in hormone receptor (HR)-positive, HER2-negative advanced breast cancer patients who progressed after aromatase inhibitor (AI) therapy. The medical records of metastatic breast cancer patients, treated with everolimus, were retrospectively reviewed to generate real life safety and efficacy data. Sixty-eight percent of the patients had received chemotherapy (for early or metastatic disease) and 26% had received chemotherapy for metastatic disease. Among the 25 included patients, the most common adverse events were fatigue, neutropenia, epistaxis, stomatitis, and pneumonitis. Toxicity led to treatment discontinuation in 3 patients (12%). The median progression-free survival (PFS) was 7 months (95%CI=3.5-10.5). With a median follow-up of 73.3 months, the median overall survival was not reached. Twenty-five percent of the patients had received prior therapy with CDK4/6 inhibitors. Median PFS was significantly shorter in this subgroup (p=0.025). There was also a trend towards a longer PFS in patients with grade 3 breast cancer (p=0.085) and in patients receiving everolimus as first-line treatment (p=0.081). Some long responses were noted, with four patients exhibiting a PFS >5 years. These real-life data show that everolimus in combination with AI in patients with HER2-negative, HR-positive advanced breast cancer is an effective treatment with an acceptable toxicity profile.