Switching Australian patients with moderate to severe inflammatory bowel disease from originator to biosimilar infliximab: a multicentre, parallel cohort study

Med J Aust. 2021 Feb;214(3):128-133. doi: 10.5694/mja2.50824. Epub 2020 Oct 17.

Abstract

Objective: To examine whether non-medical switching of patients with inflammatory bowel disease (IBD) from originator infliximab to a biosimilar (CT-P13, Inflectra) is safe and clinically non-inferior to continued treatment with originator infliximab.

Design: Prospective, open label, multicentre, parallel cohort, non-inferiority study in seven Australian hospitals over 48 weeks, May 2017 - October 2019.

Participants: Adults (18 years or older) with IBD receiving maintenance originator infliximab (Remicade) who had been in steroid-free clinical remission for at least 12 weeks.

Intervention: Managed program for switching patients in four hospitals from originator to biosimilar infliximab (CT-P13); patients in three other hospitals continued to receive originator infliximab (control).

Main outcome measures: Clinical disease worsening requiring infliximab dose escalation or change in therapy.

Results: The switch group included 204 patients, the control group 141 patients with IBD. Ten patients in the control group (7%) and 16 patients switched to CT-P13 (8%) experienced clinical deterioration; the adjusted risk difference (control v switch group) was -1.1 percentage points (95% CI, -6.1 to 8.2 percentage points), within our pre-specified non-inferiority margin of 15 percentage points. Serious adverse events leading to infliximab discontinuation were infrequent in both the switch (six, 3%) and control (six, 4%) groups.

Conclusion: Switching patients with IBD from originator to biosimilar infliximab is safe and non-inferior to continuing treatment with originator infliximab. Moreover, the introduction of biosimilar infliximab, by increasing market competition, has resulted in substantial cost savings for the Pharmaceutical Benefits Scheme.

Keywords: Crohn’s disease; Inflammatory bowel diseases; Pharmacovigilance.

Publication types

  • Equivalence Trial
  • Multicenter Study

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Australia
  • Biosimilar Pharmaceuticals / adverse effects
  • Biosimilar Pharmaceuticals / economics
  • Biosimilar Pharmaceuticals / therapeutic use*
  • Drug Costs
  • Drug Substitution
  • Female
  • Gastrointestinal Agents / adverse effects
  • Gastrointestinal Agents / economics
  • Gastrointestinal Agents / therapeutic use*
  • Humans
  • Inflammatory Bowel Diseases / drug therapy*
  • Infliximab / adverse effects
  • Infliximab / economics
  • Infliximab / therapeutic use*
  • Male
  • Middle Aged
  • Proportional Hazards Models
  • Prospective Studies
  • Severity of Illness Index
  • Treatment Outcome
  • Young Adult

Substances

  • Biosimilar Pharmaceuticals
  • Gastrointestinal Agents
  • Infliximab