Early mucosal healing with infliximab is associated with improved long-term clinical outcomes in ulcerative colitis

Background & Aims: In the Active Ulcerative Colitis Trial (ACT)-1 and ACT-2, patients with ulcerative colitis treated with infliximab were more likely than those given placebo to have a clinical response, undergo remission, and have mucosal healing. We investigated the association between early improvement (based on endoscopy) and subsequent clinical outcome. Methods: Patients underwent endoscopic evaluations at weeks 0, 8, 30, and 54 (ACT-1 only), and were categorized into 4 subgroups by week 8 (Mayo endoscopy subscore, 03). The association of week 8 endoscopy subscores, subsequent colectomy risk, symptoms and corticosteroid use outcomes were analyzed. Mucosal healing was defined as a Mayo endoscopy subscore of 0 (normal) or 1 (mild). Results: Infliximab-treated patients with lower week 8 endoscopy subscores were less likely to progress to colectomy through 54 weeks of follow-up evaluation (P =.0004). This trend was not observed among patients given placebo (P =.47). Patients with lower endoscopy subscores achieved better symptomatic and corticosteroid use outcomes at weeks 30 and 54 (P <.0001, infliximab; P <.01, placebo). Among patients who achieved clinical response at week 8, trends in subsequent clinical outcomes by week 8 endoscopy subscores were generally consistent with that for the overall patient population; no trends were observed among patients who achieved clinical remission. Conclusions: The degree of mucosal healing after 8 weeks of infliximab was correlated with improved clinical outcomes including colectomy. Similar trends were observed for all outcomes except colectomy among the subgroup with clinical response at week 8. The degree of mucosal healing at week 8 among those in clinical remission did not predict subsequent disease course.