Herceptin®, known generically as trastuzumab, is a product of Genentech, with corporate headquarters located in San Francisco, California. Trastuzumab is a humanized monoclonal antibody that binds to the HER2 receptor. It has been shown to improve treatment response rates, time to progression, and survival. It was approved in 1998 by the United States (US) Food and Drug Administration (FDA) for the treatment of metastatic disease.