Genentech's Herceptin breast cancer treatment nearly cuts in half the risk that a certain type of breast cancer will recur after surgery, the company said yesterday.
In two trials that spanned five years and included more than 5,000 volunteers, Herceptin, combined with chemotherapy, extended the life expectancy of women who have a genetic mutation that shows up in about 30 percent of breast cancer cases. The tumors of patients with the particular genetic mutation, known as human epidermal growth factor receptor 2 (HER-2) positive breast cancer, tend to grow faster and recur more often than other types of breast cancer, according to the National Cancer Institute, which sponsored the clinical trials.
"The data from these very important Phase III trials suggest for the first time that a therapy that targets women whose tumors have a specific genetic mutation has the potential to reduce the recurrence of disease in early-stage breast cancer patients," said Susan Desmond-Hellmann Genentech's president of product development. "While further follow-up is necessary, the results of this joint interim analysis suggest that adjuvant therapy with Herceptin plus chemotherapy for women with HER-2 positive breast cancer may increase the chance of long-term survival."
Dr. Edith Perez, of the Mayo Clinic in Jacksonville Florida, the principal investigator for one of the trials, told The New York Times, "This is a practice-changing result . . . the largest improvement in clinical research in breast cancer in my lifetime."
Herceptin has already been approved by the FDA as a treatment for breast cancer that has recurred after surgery. Genentech said, following the latest trials results, it would now discuss with the federal regulators the possibility of prescribing the drug to more breast cancer patients.
The trial results are expected to mean a bigger market for Herceptin which last year had sales of $483 million. Genetech said there were 34,000 women a year in the U.S. who received treatment for HER-2 positive breast cancer.