The breast cancer drug Herceptin received expanded federal approval Thursday to include treatment of some women after they have undergone surgery.
In two clinical trials, women given the drug along with chemotherapy had fewer relapses in the three years after surgery — either to remove a lump or the whole breast — than those just given standard chemotherapy, the Food and Drug Administration said in announcing the additional approval. The drug is made by Genentech Inc. of South San Francisco, Calif.
Herceptin is only for the estimated 20 percent of patients whose breast tumors churn out too much of a protein known as HER-2. About 50,000 women in the United States and 250,000 worldwide are diagnosed with this type, called HER-2 positive, each year.
In 1998, the FDA approved Herceptin to treat breast cancer after it had spread to other parts of the body. Thursday’s approval expands its use to women with cancer in the breast or lymph nodes that has been surgically removed, the FDA said.
The most serious side effect of Herceptin is heart failure. Only patients with HER-2 positive tumors, and who do not have heart failure or a weak heart, should be given the drug, also known as trastuzumab.