The purpose of this study is to evaluate the efficacy and safety of TA-650 in comparison with a control drug Polyethylene Glycol-treated Human Immunoglobulin (VGIH) in patients with Kawasaki disease refractory to initial therapy with Intravenous Immunoglobulin (IVIG). The pharmacokinetics of TA-650 is also examined.

Inclusion Criteria:

• Patients diagnosed with Kawasaki disease (incipient cases only) with 5 or more of the 6 major symptoms of Kawasaki disease.
• Patients refractory to initial IVIG therapy (a single administration at 2 g per kg body weight).
• Patients with a fever of 37.5ºC or higher axillary temperature at the time of enrollment.
• Patients to whom the study drug can be administered by day 8 of disease.

Exclusion Criteria:

• Patients who have received vaccination with Bacille Calmette-Guérin (BCG) vaccine within 6 months before the enrollment.
• Patients with a complication, or a history within 6 months before the enrollment of, serious infections requiring hospitalization.
• Patients with a complication, or a history within 6 months before the enrollment of, opportunistic infections.
• Patients complicated with active tuberculosis, active hepatitis B or C, or patients confirmed to be hepatitis B virus carriers or a history of hepatitis B.
• Patients confirmed to have HIV infection, or patients with a family history of HIV infection.
• Patients who have a history of receiving treatment with infliximab or other biological products.
• Patients who had participated in another clinical study and had received a study drug within 12 weeks before giving consent.