Afinitor (everolimus) was recently approved by the FDA for use in combination with Aromasin (exemestane). The drug combination is intended to treat some postmenopausal women with advanced hormone-receptor positive, HER2-negative breast cancer who experience cancer recurrence or progression following treatment with Femara (letrozole) or Arimidex (anastrozole).
“This is the first approval from the class of drugs known as mTOR inhibitors for the treatment of postmenopausal women with advanced hormone-receptor positive breast cancer,” said Richard Pazdur, MD, director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research.
To determine the safety and effectiveness of everolimus, researchers conducted a clinical study involving 724 patients with advanced breast cancer. All patients had experienced menopause and had estrogen receptor-positive, HER2-negative breast cancer that had spread. Previous treatments for all patients included letrozole or anastrozole. For the study, patients received either exemestane in combination with everolimus or exemestane with a placebo. Patients received treatment until their cancers progressed or side effects became intolerable.
Study results included the length of time a patient experienced progression-free survival. Compared with patients receiving placebo plus exemestane, patients who received the everolimus plus exemestane combination had a 4.6-month improvement in the median time to disease progression or death.
According to study results, the most common side effects attributed to everolimus were fatigue, diarrhea, decreased appetite, infections, mouth ulcers, and rash. Due to a higher rate of serious side effects compared with younger patients receiving the treatment, patients aged 65 years and older should be monitored closely.
Source: FDA.