Omnitarg (2C4) is a monoclonal antibody and the first in a new class of agents developed by Genentech known as HER dimerization inhibitors (HDIs). It was developed to bind to the HER-2 receptor and block the interaction between HER-2 and other HER family members (i.e. HER1/EGFR HER2 HER3 and HER4). Technically it is designed to target tumors that have normal " rather than ""overexpressed" " HER2 protein. It is relevant because it may one day represent the Herceptin equivalent"" treatment for patients who are not HER-2 positive or who are not ""strongly"" HER-2 positive.

Importantly" the positive study data relates not only to breast cancer but to other cancers as well (e.g. prostate lung ovarian colon pancreas and sarcoma).