INTRODUCTION: High body mass index (BMI) may reduce ulcerative colitis (UC) treatment efficacy. Etrasimod is an oral, once-daily (QD), selective sphingosine 1-phosphate 1,4,5 receptor modulator for the treatment of moderately to severely active UC. This post hoc analysis assessed treatment outcomes according to BMI in ELEVATE UC 52 and ELEVATE UC 12. METHODS: Patients receiving etrasimod 2 mg QD or placebo were stratified by BMI: <
25, 25-30, and >
30 kg/m 2 . Efficacy and safety were assessed at weeks 12 (pooled data) and 52 (ELEVATE UC 52 only) in addition to biomarkers assessments from week 0-12. RESULTS: For BMI <
25 (N = 443) and 25-30 kg/m 2 (N = 217) subgroups, more patients receiving etrasimod vs placebo achieved clinical remission at weeks 12 (BMI <
25 kg/m 2 : 27.9% vs 13.3%
25-30 kg/m 2 : 28.5% vs 10.0%
all P <
0.001) and 52 (BMI <
25 kg/m 2 : 30.8% vs 10.0%
25-30 kg/m 2 : 33.3% vs 6.3%
all P <
0.0001), and also for all other efficacy end points ( P <
0.05). In the BMI >
30 kg/m 2 subgroup (N = 127), more patients receiving etrasimod vs placebo achieved clinical remission at week 52 (36.5% vs 3.9%
P <
0.0001) and most other efficacy end points at weeks 12 and 52 (all P <
0.05). Overall, regardless of baseline BMI, numerically lower fecal calprotectin levels were observed with etrasimod vs placebo in treatment responders. The safety profile of etrasimod was consistent between BMI subgroups. DISCUSSION: A high BMI did not significantly affect efficacy and safety outcomes of etrasimod (NCT03945188
NCT03996369).