CP-675,206 is a fully human monoclonal antibody (mAb). It binds to the CTLA4 molecule, which
is expressed on the surface of activated T lymphocytes. CP-675,206 is thought to stimulate
patients' immune systems to attack their tumors. CP-675,206 is not expected to have a direct
effect on tumor cells. CP-675,206 been shown to induce durable tumor responses in patients
with metastatic melanoma in Phase 1 and Phase 2 clinical studies.