Subcutaneous infliximab use in children with inflammatory bowel disease in an Australian center

Experience with subcutaneous infliximab (SC-IFX) use in pediatric inflammatory bowel disease (IBD) remains limited. We aimed to evaluate the clinical efficacy, tolerability, and cost-benefit of SC-IFX as a treatment for children with IBD in a real-world setting.

A prospective, single-center cohort study was conducted at the Children's Hospital at Westmead, Australia, from February to June 2024. Thirty-three children aged 8-18 years with established IBD commenced SC-IFX (120 mg fortnightly). Assessments included clinical disease activity indices (Pediatric Crohn's Disease Activity Index [PCDAI]/Pediatric Ulcerative Colitis Activity Index [PUCAI]), biochemical markers, and infliximab levels. Patient experience was assessed via questionnaires on quality-of-life (QOL) and treatment satisfaction.

Thirty-one (31/33) children completed treatment over a 12-week follow-up period. Median infliximab levels increased from 7.8 ug/mL (interquartile range [IQR]: 5.7-11) at baseline to 19.6 ug/mL (IQR: 13.2-21.8) at Week 12 (p < 0.001). Serum infliximab level >20 ug/mL was seen in 48% of children at Week 12. Minimal change was observed in fecal calprotectin and clinical disease activity indices. High satisfaction rates with improved patient and caregiver QOL are described. Cost analyses indicated a potential for net institutional savings. Drug continuation was planned in 85% (28/33) following the 12-week study period.

Our experience suggests SC-IFX may be an effective and well-tolerated alternative to intravenous infliximab (IV-IFX) in pediatric IBD. Median serum infliximab levels increased across over the study period. Use of SC-IFX may offer a positive impact on patient and caregiver QOL, along with resource and cost saving benefits for healthcare systems. Larger-scale studies are needed to validate these findings and optimize treatment protocols.