van Hoeve K, Tabib NSS, Dreesen E, et al. - In children with inflammatory bowel disease (IBD), higher infliximab (IFX) exposure during induction therapy is linked to significantly superior endoscopic and deep remission rates at six months. From Week 4 post-induction onwards, drug concentrations distinguish remitters from non-remitters.

• From May 2017 to May 2019, all children with IBD who started IFX medication (5 mg/kg at weeks 0-2-6 and 12) for active luminal disease were included and followed prospectively.

• Thirty-two patients provided 252 serum induction concentrations (81% on concomitant thiopurines).

• From week 4 onwards, children in endoscopic remission (all in deep remission) showed significantly greater drug concentrations.

• ROC curve analysis determined that IFX TC at week 12 ≥ 5.0 μg/mL and AUC week 0-12 ≥ 4056.0 μg*day/mL were the minimal targets for achieving endoscopic remission at six months (AUROC: 0.796 [95%CI: 0.62-0.97] and AUROC: 0.778 [95%CI: 0.61-0.94], respectively).

• Furthermore, the findings suggest that proteomic analysis may aid in understanding IFX response.