Subcutaneous versus intravenous double-dose infliximab for dose intensification in young adults with Crohn's disease:...

Subcutaneous infliximab is a convenient therapeutic option with potential long-term benefits. This study aimed to compare outcomes of subcutaneous infliximab (SC) versus intravenous double-dose infliximab (Double) in Crohn's disease patients requiring treatment optimization.

We conducted a prospective comparative cohort study of 49 young adult patients with Crohn's disease who had previously received intravenous infliximab and required treatment optimization because of pharmacokinetic underexposure, defined as an infliximab trough level <3 µg/mL. Patients selected one of two treatment strategies: switching to SC infliximab (n = 25) or continuing intravenous infliximab at a doubled dose (n = 24). Treatment outcomes were assessed at baseline and at weeks 24 and 52.

Trough levels were significantly higher in the SC group at both week 24 (22.36 vs 7.12 µg/mL, p < 0.0001) and week 52 (20.6 vs 7.72 µg/mL, p < 0.0001). Predefined trough level thresholds were more frequently achieved with SC infliximab (≥5 µg/mL: 96.0% vs 70.8%, p = 0.023; ≥10 µg/mL: 96.0% vs 29.2%, p < 0.0001). At week 52, mucosal healing was achieved in 40.0% of the SC group and 37.5% of the Double group (p = 0.678).

These exploratory findings suggest that subcutaneous infliximab may provide a more stable pharmacokinetic profile, while no statistically significant between-group difference in mucosal healing was observed.