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

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.