WASHINGTON (AP) -- The Food and Drug Administration says it has approved a new form of a best-selling breast cancer drug that targets tumor cells while sparing healthy ones. It's for patients with HER2-positive, late-stage (metastatic) breast cancer.
The drug Kadcyla from Roche combines the established drug Herceptin with a powerful chemotherapy and a third chemical linking the medicines together. The chemical keeps the drugs intact until they bind to a cancer cell, where the double-shot of medication is released.
The FDA approved the new treatment for about 20 percent of breast cancer patients who have a particular form of the disease. These patients have tumors that overproduce a protein known as HER-2.
Overall, patients taking Kadcyla lived about 2.6 years, compared with 2 years for patients taking the other drugs.
FDA specifically approved the drug for patients with advanced breast cancer who have already been treated with Herceptin and taxane, a widely used chemotherapy drug.
Kadcyla will carry a boxed warning, the most severe type, alerting doctors and patients that the drug can cause liver toxicity, heart problems and potentially death. The drug can also cause severe birth defects and should not be used by pregnant women.
Breast cancer is the second leading cause of cancer-related death among women. An estimated 232,340 women will be diagnosed with breast cancer, and 39,620 will die from the disease in 2013, according to the National Cancer Institute.
The approval will help Roche build on the success of Herceptin, which has long dominated the breast cancer marketplace. The drug had sales of roughly $6 billion last year.