Discoveries
Herceptin lowers recurrence rate in early breast cancer
A "molecular age" drug that prolongs the survival of some women with advanced breast cancer can dramatically reduce the chances of recurrence in patients with early-stage disease when given for a year after standard chemotherapy.
Those are the encouraging, though preliminary, findings from an international clinical trial of the drug trastuzumab, or Herceptin, in women whose breast tumors overproduce the protein Her-2. Patients who received the drug had a 50 percent lower risk of breast cancer recurrence, which translated into an 8 percent improvement in the number of women who were disease-free two years after beginning treatment. "This is probably the biggest evidence of a treatment effect I've ever seen in oncology," says Dana-Farber's Richard Gelber, PhD, who led the data analysis for the trial. In a commentary that accompanied the published report of the trial in the New England Journal of Medicine, Harold Burstein, MD, PhD, of Dana-Farber wrote that the results have "a profound lesson: not all breast cancers are the same … Now we have made dramatic progress for patients with Her-2-positive breast tumors, who now have a much lower risk of recurrence and a better chance of survival because of trastuzumab."
Herceptin uses a laboratory-made antibody to block the activity of the Her-2 protein, which is overabundant in an estimated 20-30 percent of breast cancers. Such Her-2-positive tumors, which can be identified with a test when the breast cancer diagnosis is made, are generally more aggressive and prone to spreading than other types of breast tumors, and are resistant to many chemotherapy agents.
The international clinical trial, sponsored by Herceptin manufacturer Roche Pharmaceuticals, includes more than 5,000 women who had surgery and various types of chemotherapy before entering the study. It is expected to continue through 2008.
