NEW YORK (AP) -- Drugmakers ImmunoGen Inc. and Roche said Monday that a promising breast cancer treatment extended patients' lives in a late-stage clinical trial.
The companies did not say how much longer patients lived when they were treated with T-DM1, which is designed to deliver Roche's drug Herceptin directly to cancer cells. However, ImmunoGen said there was a "significant improvement in overall survival," or the time patients lived after the start of treatment. The trial compared T-DM1 to two other standard drugs in almost 1,000 women with a particular type of advanced breast cancer.
The companies also said Roche's U.S.-based Genentech unit also filed for marketing approval of T-DM1 and Roche will soon file for approval in Europe. Roche is also planning to start new trials of T-DM1 against earlier stages of breast cancer.
ImmunoGen, based in Waltham, Mass., does not have any products on the market. Shares of the company rose 43 cents, or 3.1 percent, to $14.27 in afternoon trading.
In June, ImmunoGen and Roche said T-DM1 delayed the progression of breast cancer by several months. The companies said patients who were treated with the drug lived almost 10 months before death or disease progression, compared to a little more than six months for patients treated with two standard drugs, Tykerb and Xeloda.
T-DM1 combines trastuzumab, which is the main ingredient in Herceptin, with a second drug and a chemical that keeps the drugs linked until they reach a cancer cell, where the cocktail can be released. ImmunoGen developed the technology that combined the drugs. If the drug is approved, ImmunoGen will get royalty payments on those sales.
The trial involved 991 women with HER-2 positive breast cancer, a more aggressive type of the disease that is less responsive to hormone therapy.
In a note to clients, Cowen & Co. analyst Simos Simeonidis said he expects the Food and Drug Administration to approve T-DM1 in the first half of 2013. He said the drug appears to be very effective and safe, and it should quickly gain acceptance as a secondary treatment for breast cancer.