Pfizer has out-licensed tremelimumab, a fully human CTLA-4 (cytotoxic T-lymphocyte antigen 4) monoclonal antibody that previously demonstrated unimpressive efficacy in a Phase III trial for advanced melanoma, to AstraZeneca’s MedImmune, which plans to explore the drug for a number of potential cancer indications. Pfizer retains rights to use the drug candidate with specified types of combination therapies. Although oncology is a priority therapy area for the company, it is apparent that Pfizer wishes to focus its pipeline on targeted therapies.