Phase I dose escalation trial of tremelimumab (CP-675,206) administered in combination with PF-3512676 in patients with melanoma or other advanced cancers

3046 Background: Tremelimumab, a fully human monoclonal antibody specific for cytotoxic T-lymphocyte antigen 4 (CTLA4), and PF-3512676, an oligodeoxynucleotide toll-like receptor 9 agonist, are both novel, targeted immune modulators that can elicit durable antitumor responses in patients with advanced cancer. The tolerability of the combination of these two agents was investigated. Methods: Eligibility criteria included advanced melanoma or other advanced cancer, ECOG performance status of 0 or 1, and no history of autoimmune disease. Patients received intravenous tremelimumab (6.0, 10.0, or 15.0 mg/kg) every 12 weeks plus 0.05 mg/kg subcutaneous PF-3512676 weekly. Further escalation of PF-3512676 (to 0.1 mg/kg and 0.2 mg/kg) was planned once the MTD of tremelimumab had been determined. Primary endpoint was safety of the treatment combination; secondary endpoints included clinical activity, pharmacokinetics (PK), and immunologic measurements. Results: To date, 15 patients (melanoma, n = 12; mesothelioma, ...