Endoscopic Response to Subcutaneous Infliximab by Disease Location: A Post Hoc Analysis of the LIBERTY-CD Study

The efficacy of targeted therapies for patients with Crohn's disease (CD) varies by disease location, with the terminal ileum being the most challenging segment to treat despite its frequent involvement. We investigated the efficacy of subcutaneous infliximab (IFX SC) in patients with moderately to severely active CD according to disease location using data from the phase III LIBERTY-CD trial.

This analysis included week (W) 10 responders to intravenous IFX induction therapy who were randomized to receive IFX SC 120 mg every 2 weeks or placebo (PBO) during maintenance therapy. Patients were grouped according to baseline disease location (ileum-dominant or colon-dominant), and outcomes were assessed up to W54. Endoscopic response was also evaluated at the segmental level. Factors associated with W54 outcomes were assessed according to disease location.

Among 329 patients, 52.6% had colon-dominant CD (n = 173), and 47.4% had ileum-dominant CD (n = 105). Baseline characteristics were comparable between groups. At W54, IFX SC significantly improved all efficacy endpoints vs PBO, even though PBO-treated patients may have experienced residual treatment effects from intravenous IFX induction therapy. Treatment effects were similar regardless of disease location. In both location groups, clinical remission and endoscopic response at W54 correlated with higher serum IFX levels at W14 and W54. Endoscopic responses at W54 were greater with IFX SC vs PBO across all ileocolonic segments, including the terminal ileum, with consistent treatment effect sizes observed throughout each segment.

Although ileal disease is often more treatment resistant, IFX SC maintenance therapy was effective vs PBO regardless of disease location, demonstrating consistent efficacy across segments including the terminal ileum.