Biological therapy (also known as immunotherapy, biotherapy, or biological response modifier-BRM-therapy) uses biological agents (drugs) to stimulate, enhance, modify, repair, or manipulate the immune system to fight infection, cancer, or other diseases.
One type of biologic therapy that has evolved in breast cancer is monoclonal antibody therapy. Monoclonal antibody therapy is a type of biologic therapy that has been found to be effective in fighting certain types of cancer. Antibodies are proteins made by the body's own immune system that are directed against foreign and infectious agents, called antigens. Monoclonal antibodies are antibodies developed in a laboratory as medicines to provide specific anticancer action in humans. For example, the drug, Herceptin® (trastuzumab), is a monoclonal antibody used to treat breast cancer patients who are positive for the gene HER2.