S1985 Early Symptomatic Improvement Associations With Week 12 Outcomes: E-Diary Results From the Etrasimod ELEVATE UC Clinical Program

Introduction: Etrasimod is an oral, once-daily (QD), selective sphingosine 1-phosphate (S1P)1,4,5 receptor modulator for the treatment of moderately to severely active ulcerative colitis (UC). Early patient (pt)-reported response is often seen as an indicator of continued improvement through Week (Wk) 12. Methods: This post hoc analysis investigated relationships between pt-reported symptoms by Day 7 and clinical endpoints at Wk 12 in pts receiving etrasimod 2 mg QD or placebo in the ELEVATE UC clinical program (NCT03945188, NCT03996369) using rectal bleeding (RB) and stool frequency (SF) subscores reported via daily e-diary records. For pts reporting symptomatic, RB, and SF response by Day 7 (yes/no), the proportion achieving clinical endpoints (clinical remission [CR], endoscopic improvement [EI], and EI-histologic remission [EIHR]) at Wk 12 was measured. Adjusted risk differences in proportions of responders between treatment groups were estimated and tested using the Mantel–Haenszel weighted method. Results: Among pts reporting symptomatic response by Day 7 (etrasimod 2 mg, N1 = 151; placebo, N1 = 60), pts treated with etrasimod vs placebo demonstrated significantly greater CR (47.7% vs 15.0%, adjusted difference [Δ] 33.9, P < 0.001), EI (54.3% vs 20.0%, Δ 35.7, P < 0.001), and EIHR (31.1% vs 6.7%, Δ 24.8, P < 0.001) rates at Wk 12 . In pts who did not demonstrate symptomatic response by Day 7 (etrasimod 2 mg, N1 = 376; placebo, N1 = 200), those treated with etrasimod vs placebo achieved significantly greater rates of CR (18.9% vs 10.0%, Δ 8.7, P = 0.002), EI (27.7% vs 17.0%, Δ 10.5, P = 0.002), and EIHR (16.0% vs 7.5%, Δ 8.3, P = 0.002) at Wk 12 . Similarly, Day 7 RB and SF responders and nonresponders treated with etrasimod vs placebo also demonstrated significantly greater rates of CR, EI and EIHR at Wk 12 (all P < 0.001). Conclusion: Pts treated with etrasimod may experience rapid symptomatic improvements. In ELEVATE UC, pts treated with etrasimod who both did and did not demonstrate rapid symptomatic improvements had higher rates of clinical endpoint achievement at Wk 12 vs placebo. Pts treated with etrasimod who demonstrated an early, Day 7 response had the greatest likelihood of meeting clinical endpoints at Wk 12. Pfizer’s generative artificial intelligence tool MAIA was used to assist production of the abstract first draft. Authors reviewed/edited and take responsibility for the content.