Genentech fires new shot at breast cancer

A “smart bomb” that targets breast cancer cells while minimizing collateral damage to healthy cells is pushing Genentech Inc. toward its fourth cancer drug approval in 18 months. Trastuzumab emtansine, or T-DM1, which the South San Francisco-based U.S. subsidiary of drug giant Roche AG submitted to the Food and Drug Administration in August, could be approved by the end of February. That timeline is good news for patients, some of whom have pushed the FDA to speed approval of the drug, which piggybacks a chemotherapy agent by ImmunoGen Inc. onto Genentech’s long-running cancer drug Herceptin.