The New York Times reports that the drug is called Afinitor, and appears to expand the time that endocrine therapy is able to keep the disease in check. It has been approved for use by a big segment of breast cancer patients, those who are postmenopausal women who have hormone receptor-positive disease.
These women are usually treated with aromatase inhibitors, which will deprive the tumors of the hormone estrogen, which can fuel the tumors’ growth. The tumors can also become resistant to those drugs, but the addition of the new Afinitor drug seems to restore their effectiveness. Dr. Melody Cobleigh, director of the breast cancer program at Rush University Medical Center in Chicago, stated:
“It’s exciting. We have figured out a way that tumor cells become resistant to existing therapies and a way to reverse that resistance.”
According to The Wall Street Journal, Afinitor’s approval for breast cancer was based on a study that involved 724 patients with advanced breast cancer, who were previously treated with Femara (another Novartis drug), or Arimidex (marketed by AstraZeneca). Patients wither received Afinitor in combination with Aromasin, or Aromasin with a placebo, or fake medicine. They received the treatment until either their breast cancer progressed or side effects became unacceptable.
The study’s main design was to allow scientists to measure the length of time a patient lived without their cancer becoming worse, or until progression-free survival. Those patients who took Afinitor and Aromasin saw an average of 4.6 months until their disease either got worse or they passed away, when compared to those receiving Aromasin and the placebo pill.
The most common side effects of the drug were mouth ulcers, infections, rash, fatigue and diarrhea. The FDA noted in their approval that patients who are 65 and over will need to be monitored closely, because they experienced serious side effects more often than younger patients.
The FDA stated in a press release that Richard Pazdur, M.D., director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research commented:
“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. Afinitor is another example of the value of continuing to study drugs in additional types of cancer after their initial approval.”
The new Novartis drug Afinitor is now the first treatment to boost the effectiveness of endocrine therapy for patients suffering from late-stage breast cancer.