OBJECTIVES: Based on the results of the randomized phase III BOLERO-2 study, the everolimus plus exemestane combination was approved and is reimbursed in the Czech Republic in hormone-receptor (HR) positive, human epidermal growth factor receptor type 2 (HER-2) negative metastatic breast cancer after prior aromatase inhibitor therapy. However, the real-world outcomes are unknown.

METHODS: We retrospectively evaluated HR-positive, HER-2 negative mBC patients with discontinued everolimus treatment in comprehensive cancer centre in the Czech Republic. The cost of drug and outcomes in the real-life clinical practice were assessed and compared to registration study BOLERO-2 (phase III clinical trial results: median age 62 years; median duration of exposure to everolimus was 5.0 months with median PFS 10.6 months, dose interruptions or reductions were required in 66.8% of patients).

RESULTS: A total of 73 patients with mBC (median age 64 years) were treated with everolimus plus exemestane in the Masaryk Memorial Cancer Institute between 2014 – 2017. The median duration of treatment was 5.98 months, median progression-free survival was 6.6 months, the mean everolimus cost according to individual drug consumption was EUR 22,190 (CZK 572,491; EUR 1 = CZK 25.8). Adverse events led to dose reductions and/or discontinuation of treatment in 27 (37%) patients.

CONCLUSIONS: The real-world evidence confirms that everolimus and exemestane is an effective and safe treatment in HR-positive, HER-2 negative patients with mBC after previous therapy with non-steroidal aromatase inhibitor. Nevertheless, the real-world PFS, which is the key driver in all cost-effectiveness models based on BOLERO-2 results, was apparently lower than in the clinical trial settings.