Real-world Safety and Effectiveness of Infliximab in Pediatric Patients With Acute Kawasaki Disease A Postmarketing Surveillance in Japan (SAKURA Study)

Background: In 2015, infliximab was approved for the treatment of patients with intravenous immunoglobulin-refractory Kawasaki disease (KD) in Japan. However, limited real-world data exist on the usefulness of infliximab for acute KD patients. We conducted a postmarketing surveillance study in patients with acute KD refractory to conventional therapies to evaluate the safety (including any live vaccine-related infections) and the effectiveness of infliximab. Methods: This was a multicenter, prospective, open-label, single-cohort, observational study in patients with acute KD refractory to conventional therapy who were prescribed a single 5 mg/kg dose of infliximab. Safety and effectiveness of infliximab were evaluated at 1 month, and live vaccine-related infections were further observed until 6 months from KD onset. Effectiveness assessments included fever resolution rate, the incidence of coronary artery lesions and change in coronary diameter Z scores. Results: A total of 291 patients were enrolled, and all patients completed the study. Adverse drug reactions and serious adverse drug reactions were reported in 12.4% and 3.1% of patients, respectively. Live vaccine-related infections were not observed. In the 208 patients with effectiveness assessments, the fever resolution rate within 48 hours after infliximab infusion was 77.4% (95% confidence interval: 71.1-82.9). Median time until fever resolution was 16.6 hours. After infliximab administration, the incidence (at baseline: 10.9%; at the final observation point: 12.0%; maximum value: 14.6%) and severity of coronary artery lesions did not change notably. Conclusions: In this study, Infliximab for patients with acute KD refractory to conventional therapies was well tolerated and effective.