Switching to Subcutaneous Infliximab for Regaining Clinical Remission in Inflammatory Bowel Disease Patients who lost response to Intravenous Infliximab: An Observational Study from the ENEIDA Registry

Abstract

Background Subcutaneous infliximab (SC-IFX) has demonstrated efficacy and safety in maintaining clinical remission in patients with inflammatory bowel disease (IBD). However, its role in re-inducing remission in patients with active disease who have lost response to intravenous infliximab (IV-IFX) has been poorly studied. The aim of this study was to assess the usefulness of switching from IV-IFX to SC-IFX in patients with active IBD who had lost response to intravenous treatment.

Methods A retrospective, observational, multicentre study was conducted using data from the ENEIDA registry of GETECCU. Patients with Crohn’s disease (CD), ulcerative colitis (UC), or unclassified IBD (IBDU) who switched from IV-IFX to SC-IFX while presenting clinical activity were included. Clinical, biochemical, and pharmacokinetic data were collected at the time of the switch and during follow-up (weeks 8 and 16, and at 6 and 12 months). Clinical activity was defined as a Harvey–Bradshaw Index (HBI) ≥5 for CD or a partial Mayo Index (PMI) >2 for UC; clinical response as a reduction of ≥ 3 points; and clinical remission as HBI <5 or PMI ≤2.

Results A total of 95 patients were included (66 CD, 26 UC, 3 IBDU), with a mean age of 46.4 ± 15.5 years; 47.4% were female, see Table 1. The main reason for switching was pharmacokinetic failure (33.7%, n = 32). Treatment was withdrawn in 4.2% of patients before week 8. At week 8, 73.7% (n = 70) achieved clinical response and 48.4% (n = 46) achieved clinical remission. Clinical response/remission rates were 72.6/57.9% at week 16, 71.6/55.8% at 6 months, and 47.5/38.9% at 12 months. Faecal calprotectin decreased from 743 to 524 μg/g and C-reactive protein from 2.5 to 1.4 mg/dL at 12 months. IFX levels increased from 7.8 to 17.2 μg/mL at week 16. Treatment persistence with SC-IFX, assessed by Kaplan–Meier analysis, was high overall, with estimated survival probabilities of 88.5% at 12 months in CD and 69.2% in UC. Adverse events were reported in 7.4% of patients, with only two treatment discontinuations.

Conclusion Switching from IV-IFX to SC-IFX may be a safe and effective strategy to re-induce clinical remission in patients with active IBD who lose response to IV-IFX.