Final results of a phase II study of nivolumab in Japanese patients with relapsed or refractory classical Hodgkin lymphoma

Background: Many patients with classical Hodgkin lymphoma show increased programmed death-1 ligand expression in Reed-Sternberg cells. We report the final results of a phase II study of nivolumab, an anti-programmed death-1 monoclonal antibody, in Japanese patients with relapsed or refractory classical Hodgkin lymphoma. Methods: Japanese patients with previously treated classical Hodgkin lymphoma (aged ≥ 20 years) were administered nivolumab (3 mg/kg on Day 1 of 14-day cycles) until progressive disease, an unacceptable adverse event, or another clinically relevant reason. Treatment could continue beyond progressive disease at the investigator's discretion in selected patients. Results: Seventeen patients (median age: 63.0 years) were enrolled. The median follow-up was 38.8 months. One patient with non-Hodgkin lymphoma was excluded from efficacy analyses. The centrally assessed overall response rate in 16 classical Hodgkin lymphoma patients was 87.5% (95% confidence interval = 61.7-98.4%) and the disease control rate was 93.8% (95% confidence interval = 69.8-99.8%). The median (95% confidence interval) duration of response and progression-free survival were 8.5 (2.4-12.6) and 11.7 (1.8-42.3) months, respectively. The 3-year overall survival rate was 80.4% (95% confidence interval = 50.6-93.2%). Nivolumab was continued beyond progressive disease in seven patients; six were alive at the data cut-off. Adverse drug reactions occurred in all 17 patients with grades 3-4 adverse drug reactions in eight patients and no grade 5 adverse drug reactions. Pulmonary toxicities occurred in five patients; four of these occurred ≥17 months after starting nivolumab. Conclusion: Nivolumab is effective and tolerable in Japanese relapsed or refractory classical Hodgkin lymphoma patients. Continued monitoring may be necessary to detect late-onset pulmonary toxicities.