ABSTRACT: The human IgG4 monoclonal antibody nivolumab targets programmed cell death-1 (PD-1) and promotes antitumor response by blocking the interaction of PD-1 with its ligands. This single-center phase Ib study investigated the tolerability, safety, and pharmacokinetics of nivolumab combined with standard chemotherapy in patients with advanced non-small-cell lung cancer (NSCLC).Patients who had stage IIIB without indication for definitive radiotherapy, stage IV, or recurrent NSCLC were eligible. Regimens were nivolumab 10 mg/kg + gemcitabine/cisplatin (arm A), pemetrexed/cisplatin (arm B), paclitaxel/carboplatin/bevacizumab (arm C), or docetaxel (arm D). Regimens A, B, and D were repeated every 3 weeks for up to four cycles and regimen C was repeated for up to six cycles; nivolumab alone (arm A), with pemetrexed (arm B), bevacizumab (arm C), or docetaxel (arm D) was continued every 3 weeks as maintenance therapy until disease progression or unacceptable toxicity. Dose-limiting toxicity (DLT) was evaluated during the first treatment cycle.As of March 2014, six patients were enrolled in each arm. The combination of nivolumab 10 mg/kg and chemotherapy was well tolerated. DLT was observed in only one patient in arm A (alanine aminotransferase increased). Select adverse events (those with a potential immunologic cause) of any grade were observed in six, four, six, and five patients in arms A, B, C, and D, respectively. Three, three, six, and one patient achieved partial response while median progression-free survival was 6.28, 9.63 months, not reached, and 3.15 months in arms A, B, C, and D, respectively.Combination of nivolumab 10 mg/kg and chemotherapy showed an acceptable toxicity profile and encouraging antitumor activity in patients with advanced NSCLC.Japanese Pharmaceutical Information Center Clinical Trials Information (JapicCTI)-132071.