
SOUTH SAN FRANCISCO-Genentech Inc. has issued a “Dear Doctor” letter to alert physicians to 62 postmarketing reports of serious adverse events related to the use of trastuzumab (Herceptin), the company’s anti-HER-2 monoclonal antibody for use in treating HER-2-positive breast cancer. To date, about 25,000 women have been treated with Herceptin worldwide.

