Comparison of Long-Term Outcomes of Infliximab versus Adalimumab Treatment in Biologic-Naïve Patients with Ulcerative Colitis

Abstract

Background/aims: The tumor necrosis factor-α inhibitors infliximab and adalimumab are standard treatments for moderate to severe ulcerative colitis (UC). However, there has been no headto- head comparison of treatment efficacy and outcomes between the two agents. The aim of this study was to compare the efficacy and long-term outcomes of infliximab versus adalimumab treatment in biologic-naïve patients with UC.

Methods: We retrospectively analyzed the records of 113 biologic-naïve patients with UC who were treated between September 2012 and December 2017 (the infliximab group [n=83] and the adalimumab group [n=30]). We compared remission and response rates between these groups at 8 and 52 weeks. We used Kaplan-Meier curves to compare long-term outcomes, and logistic regression analysis and Cox-proportional hazard regression models to assess factors affecting outcomes.

Results: The median follow-up duration was 25.8 months. Baseline clinical characteristics were similar between groups. There were no significant differences between the two groups in the rate of clinical remission or clinical response at 8 or 52 weeks. Multivariate analyses also showed that long-term outcomes were not significantly different (adjusted hazard ratio [HR], 1.45; 95% confidence interval [CI], 0.81 to 2.56; p=0.208). An elevated C-reactive protein level (greater than 5 mg/L) was a significant predictive factor for poor outcomes (adjusted HR, 2.25; 95% CI, 1.37 to 3.70; p=0.001). During the follow-up period, the rates of adverse event were not significantly different between the two groups (p=0.441).

Conclusions: In our study, infliximab and adalimumab had similar treatment efficacy and longterm outcomes in biologic-naïve patients with moderate to severe UC.

Keywords: Adalimumab; Colitis; Comparative study; Infliximab; Tumor necrosis factor-alpha; ulcerative.

Conflict of interest statement

CONFLICTS OF INTEREST

No potential conflict of interest relevant to this article was reported.

Figures

Fig. 1

Flowchart of study cohort enrollment and identification of ulcerative colitis (UC) in biologic-naïve patients treated with tumor necrosis factor-α (TNF-α) inhibitors infliximab or adalimumab.

Fig. 2

Kaplan-Meier curves for cumulative outcomes in tumor necrosis factor (TNF)-α treated patients with ulcerative colitis (UC) (1-rate of each event). (A) Poor outcomes.* (B) All-cause hospitalization rate. (C) UC-related hospitalization rate. (D) Corticosteroid prescription rate. (E) TNF-α inhibitor discontinuation rate. (F) Rate of switching to a secondary TNF-α inhibitor. IFX, infliximab; ADA, adalimumab. *Poor outcomes are defined as the sum of the following events: all-cause hospitalization, UC-related hospitalization, corticosteroid prescription, discontinuation of TNF-α inhibitors, and switching to a secondary TNF-α inhibitor.

Fig. 3

Kaplan-Meier curve of cumulative outcomes based on baseline C-reactive protein (CRP) levels in patients with ulcerative colitis treated with tumor necrosis factor (TNF)-α inhibitors (1-rate of poor outcome event). *Poor outcomes are defined as the sum of the following events: all-cause hospitalization, ulcerative colitis-related hospitalization, corticosteroid prescription, discontinuation of TNF-α inhibitors, and switching to a secondary TNF-α inhibitor.

Fig. 4

Subgroup Kaplan-Meier curves of cumulative outcomes based on baseline C-reactive protein (CRP) levels in patients with ulcerative colitis (UC) treated with tumor necrosis factor (TNF)-α inhibitors (1-rate of poor outcome events). (A) Infliximab group. (B) Adalimumab group. *Poor outcomes are defined as the sum of the following events: all-cause hospitalization, UC-related hospitalization, corticosteroid prescription, discontinuation of TNF-α inhibitors, and switching to a secondary TNF-α inhibitor.