Efficacy and Safety of Immunoglobulin Plus Firsekibart in Patients With Kawasaki Disease

Efficacy and Safety of Immunoglobulin Plus Firsekibart in Patients With Kawasaki Disease: An Exploratory Randomized Controlled Study

This study evaluates the efficacy and safety of the addition of Firsekibart to standard initial treatment (intravenous immunoglobulin [IVIG] plus aspirin) in children with Acute Kawasaki Disease (KD) .

This is a two-center, open-label, randomized controlled exploratory clinical trial in China. The investigators will enroll KD pediatric patients within 10 days of illness onset. Participants will be randomly assigned in a 1:2 ratio to the experimental group (receiving 3 mg/kg Firsekibart plus 2 g/kg IVIG and 30 mg/kg aspirin) or the control group (receiving 2 g/kg IVIG and 30 mg/kg aspirin). Baseline characteristics of each participant will be collected, including sex, age at onset, height, body weight, subtype of KD, fever days before initial IVIG, echocardiographic findings at enrolment, and a series of pre-IVIG laboratory tests. Two-dimensional echocardiography will be performed at admission, 2 weeks, 1 month, 3 months, and 6 months after illness onset to assess the coronary artery lesions. This study aims to determine the therapeutic potential of standard therapy combined with Firsekibart in the acute phase of KD for reducing the incidence of coronary artery lesions (CAL) , decreasing IVIG resistance, and improving inflammation control.

Inclusion Criteria:

1. Meeting diagnostic criteria for Kawasaki disease (KD) released by American Heart Association (AHA) in 2024
2. Diagnosed before the tenth day of illness (with the first day of illness defined as the first day of fever)
3. Not treated with IVIG yet
4. Age >28 days，<18 years

Exclusion Criteria:

1. Receiving steroids or other immunosuppressive agents in the previous 30 days;
2. With a previous history of KD;
3. Afebrile before enrolment;
4. Contraindications for subcutaneous injection, including severe local skin infection, ulceration, etc;
5. Known hypersensitivity to immunoglobulins, Firsekibart, or any of the excipients;
6. With suspected infectious diseases including sepsis, septic meningitis, peritonitis, bacterial pneumonia, varicella and influenza, etc;
7. With serious immune diseases, such as immunodeficiency, or chromosomal abnormalities;
8. With severe hepatic dysfunction (ALT > 3 times the upper limit of normal) prior to treatment
9. Unwillingness to provide written informed consent;
10. Unlikely to complete at least 3 months of follow-up;
11. Any other conditions deemed unsuitable for enrolment by investigators.