Drugs that enhance the body’s immune response (immunotherapies) may help patients with small cell lung cancer (SCLC). Immunotherapy may be beneficial on its own, but could also complement standard chemotherapy. An overview of recent studies and ongoing clinical trials highlighted several promising immunotherapies, including ipilimumab (Yervoy). Yervoy, which has been approved to treat certain kinds of skin cancer, targets a protein called CTLA4, which acts as an "off switch" on immune system cells. By deactivating CTLA4, Yervoy allows the immune system to continue attacking tumors. Another immune treatment that may be combined with traditional chemotherapy is interferon-alpha, a molecule that stimulates the body’s immune cells.