Endoscopic, Histologic, and Composite Endpoints in Patients With Ulcerative Colitis Treated With Etrasimod

Background & aims: Histologic remission, a potentially important treatment target in ulcerative colitis (UC), is associated with favorable long-term outcomes. Etrasimod is an oral, once-daily, selective sphingosine 1-phosphate (S1P)_1,4,5 receptor modulator for the treatment of moderately to severely active UC. This post-hoc analysis of the ELEVATE UC program evaluated the efficacy of etrasimod according to histologic and composite (histologic/endoscopic/symptomatic) endpoints and examined their prognostic value.

Methods: Patients with moderately to severely active UC were randomized 2:1 to once-daily oral etrasimod 2 mg or placebo. Histologic and composite endpoints, including disease clearance (endoscopic/histologic/symptomatic remission), were assessed at Weeks 12 (ELEVATE UC 52; ELEVATE UC 12) and 52 (ELEVATE UC 52). Logistic regressions examined associations between baseline and Week 12 histologic/composite endpoints and Week 52 outcomes.

Results: At Weeks 12 and 52, significant improvements with etrasimod vs placebo were observed in histologic/composite outcomes, including endoscopic improvement-histologic remission and disease clearance. The proportion of patients treated with etrasimod achieving clinical remission at Week 52 was higher among those with disease clearance at Week 12 vs those without disease clearance (73.9% [17/23] vs 28.3% [71/251]). Histologic improvement and endoscopic improvement at Week 12 were moderately and strongly associated with clinical remission at Week 52 (odds ratio [OR], 2.37; 95% confidence interval [CI], 1.27-4.41; and OR, 6.36; 95% CI, 3.47-11.64, respectively). Histologic remission and endoscopic improvement at Week 12 were strongly associated with endoscopic improvement-histologic remission at Week 52 (OR, 3.21; 95% CI, 1.70-6.06 and OR, 5.47; 95% CI, 2.89-10.36, respectively).

Conclusions: Etrasimod was superior to placebo for achievement of stringent histologic and composite endpoints.

Clinicaltrials: gov, Number: NCT03945188; ClinicalTrials.gov, Number: NCT03996369.