Mirikizumab in Paediatric UC (SHINE-1 Trial): Lancet Gastroentrol Hepatolo, February 2026
Introduction
Ulcerative colitis (UC) in children is often aggressive and difficult to manage, with many patients failing conventional therapies such as corticosteroids, immunomodulators, biologics, or JAK inhibitors. Mirikizumab, a humanised monoclonal antibody targeting the p19 subunit of interleukin-23 (IL-23), has demonstrated efficacy in adults with UC and Crohn’s disease. However, evidence in the paediatric population remains limited. The SHINE-1 trial was designed to evaluate the pharmacokinetics, efficacy, and safety of mirikizumab in children with moderately-to-severely active UC who had inadequate response or intolerance to prior therapies.
Summary
SHINE-1 was a 52-week, multicentre, open-label phase 2 trial conducted across 19 centres in North America, Asia, and Israel. A total of 26 paediatric patients (2–<18 years) with moderate-to-severe UC received weight-adjusted intravenous mirikizumab at weeks 0, 4, and 8, followed by subcutaneous maintenance therapy.
At week 12, clinical response rates were encouraging: 69% achieved clinical response, and 38.5% achieved clinical remission based on the modified Mayo score. Endoscopic remission occurred in 53.8%, and symptomatic remission in 46.2% of patients.
At week 52, sustained efficacy was observed:
53.8% maintained clinical response
38.5% remained in clinical remission
50% achieved remission based on Pediatric Ulcerative Colitis Activity Index (PUCAI)
38.5% achieved corticosteroid-free remission
Safety outcomes were acceptable. Only 12% experienced serious adverse events, and treatment discontinuation occurred in one patient (4%). The most common adverse events included COVID-19 infection, injection-site pain, headache, and fever.
Conclusion
The SHINE-1 trial demonstrates that mirikizumab is a promising IL-23–targeted therapy for paediatric moderate-to-severe ulcerative colitis, showing meaningful clinical, endoscopic, and symptomatic improvements with an acceptable safety profile. These findings support larger controlled trials to confirm its role in paediatric UC management.