Subcutaneous infliximab in inflammatory bowel disease: from pharmacokinetic principles to clinical practice.

Abstract

INTRODUCTION Subcutaneous infliximab (CT-P13 SC) was developed to address the pronounced peak-to-trough fluctuations of intravenous dosing and the immunogenicity driven by sub-therapeutic troughs. Through a stable steady-state pharmacokinetic profile it meets the international Delphi consensus definition of a biobetter, although this is not a regulatory designation. AREAS COVERED This narrative review synthesizes pivotal Phase 3 trial data, randomized comparisons of continued intravenous versus subcutaneous maintenance, real-world switching cohorts, individual participant data meta-analyses, and emerging evidence on therapeutic drug monitoring recalibration, immunomodulator de-escalation, and special populations including obesity, perianal disease, pediatric inflammatory bowel disease, and pregnancy. MEDLINE, Embase, and the Cochrane Library were searched from inception to August 2026. EXPERT OPINION Subcutaneous infliximab is positioned to become the default maintenance route for most patients, with intravenous administration reserved for acute, high-burden induction. Within five years, fully subcutaneous pathways, immunomodulator de-escalation guided by steady-state levels, and dosing informed by individual clearance are expected to move from research questions to standard practice.