Investigator-initiated, multi-center, single-arm, open-label study of the effectiveness of canakinumab in Japanese patients with Schnitzler syndrome
Naotomo Kambe, Mayuko Yamamoto, Koji Takemura, Shin‐ichiro Kagami, Yoshie Kawahara, Hajime Yoshifuji, Tomoyasu Jo, Kazushi Izawa, Satoshi Nakamizo, Norimitsu Inoue, Tatsuya Ito, Yoko Amino, Yumiko Ibi, Satoshi Morita, Nobuo Kanazawa
Abstract
BACKGROUND: Schnitzler syndrome is an adult-onset autoinflammatory disease characterized by an urticaria-like rash and monoclonal gammopathy with fever and fatigue. Although some treatments have shown efficacy in clinical trials, no approved treatment exists. We aimed to assess canakinumab, an anti-IL-1β monoclonal antibody, in Japanese patients. METHODS: This phase II, multicenter, single-arm, open-label study enrolled five patients with active disease from four hospitals. Patients received a single subcutaneous dose of canakinumab 150 mg. The primary endpoint was the proportion of patients achieving a complete clinical response (CR), based on physician global assessment on Day 7. If a CR was not achieved on Day 7 or by 8 weeks post-treatment, the dose was increased to 300 mg. Dosing continued every 8 weeks until 24 weeks. The study also evaluated patient-reported disease activity and changes in acute inflammatory markers, including white blood cell count, neutrophil count, C-reactive protein concentration, and serum amyloid A level. Quality of life was assessed using the Dermatology Life Quality Index and the 36-item Short Form health survey. Safety was also evaluated. RESULTS: Sixty percent (3/5) of patients had a CR on Day 7. One of the remaining two patients had a CR 7 days after the dose was increased to 300 mg. All five patients, including those who did not achieve a CR, showed improvement in inflammatory markers and quality of life scores, and no new adverse events were detected. CONCLUSIONS: In this trial, canakinumab showed a potential for usefulness in Japanese patients with Schnitzler syndrome.