Comparative Long-term Efficacy and Safety of Infliximab and Adalimumab in Patients with Crohnʼs Disease: A Retrospective Study from the McGill University Health Center

Abstract

Introduction: The long-term efficacy and safety of the anti tumor necrosis factor (TNF) agents infliximab (IFX) and adalimumab (ADA) has been well established in the treatment of Crohn's disease (CD). However, direct head to head studies comparing the two agents over long periods of time are sparse. The aim of our study was to compare the long-term efficacy and safety of IFX and ADA in the treatment of CD at the McGill University Health Centre (MUHC). Methods: This is a single center retrospective study based at the MUHC. We included adult patients with CD that were anti-TNF naive and were treated with either IFX or ADA. Patient's were excluded if they did not complete at least 1 year of anti-TNF therapy. A chart review was performed and demographic, clinical, laboratory, and endoscopic data were retrieved. Clinical remission was defined as HBI≤4, response was defined as decrease in HBI≥2, and durable remission was defined remission at all time points. Clinical remission and response and durable remission and response were assessed annually and up to 5 years of treatment. Occurrence of treatment failure defined as hospitalization, need for steroids, or surgery were compared. Safety data was also analyzed. Results: Our study included a total of 141 patients with 61 patients in the ADA group and 80 patients in the IFX group. Certain differences were noted between the IFX and ADA groups, but not regarding disease activity (Table 1). Efficacy analysis showed that patients treated with ADA were more likely to respond to therapy at 12 months compared to IFX (93% vs 79%, p=0.0405). Otherwise, remission rates were not different between groups at 1,2,3,4 and 5 years and response rates at 2, 3, 4 years were also similar between groups. Durable remission was achieved in 50% (30/60) of the ADA group and in 46% (36/78) of the IFX group (p=0.7317). Use of combination therapy was associated with higher rates of response at 12 months (75% vs 50%, p=0.01). Rates of steroid use, hospitalization or surgery were not different amongst the two groups. Adverse events were noted in 23.7% of patient on IFX compared to 13.1% in patients on ADA, with the two most common being infusion reaction and arthralgia (p=0.13). No new case of malignancy was noted in either group.Table 1: Baseline Characteristics of the 141 patients included in the studyConclusion: Our real life head to head data demonstrates similar efficacy and safety between IFX and ADA and confirms the superiority of combination therapy. Further larger studies are required to investigate these findings.