S1815 Early Response to Vedolizumab in Patients With Crohn's Disease in a Prospective Observational Study in Canada and US: The VOICE Study

Introduction: VOICE (NCT06249555) is a prospective, observational study in adult (≥18 yrs) pts with Crohn’s disease (CD) in Canada and the United States initiating vedolizumab (VDZ) treatment (tx) as part of standard care. The aim is to explore the response to VDZ measured by Patient-Reported Outcomes Measurement Information System (PROMIS) Short Form (SF) scores in the following domains: pain interference, fatigue, anxiety, depression, physical function, sleep disturbance, and ability to participate in social roles or activities. Methods: Inclusion criteria include baseline PROMIS Pain Interference (PI)-SF T-score ≥55 (0.5 SD above general population). The primary endpoint is time to first meaningful clinical improvement in PROMIS PI-SF T-score (≥2-point decrease from baseline). Other endpoints include: improvement in 7 PROMIS domains (5-point (0.5 SD) change in T-score from baseline); Short Inflammatory Bowel Disease Questionnaire (SIBDQ) improvement (≥9 point increase from baseline) and remission (score of ≥60); and safety. Here, we report results from pts with ≥1 VDZ dose and ≥1 post-baseline PI assessment included in an interim analysis (IA; prespecified to occur after 50 pts completed or discontinued before wk 14). Results: Overall, 64 pts with ≥1 VDZ dose and ≥1 post-baseline PROMIS PI assessment (mean ± SD age, 43.1 ± 17.0 years, 35.9% male, 92.2% White) were included in the IA. Disease duration (mean ± SD) was 6.4 ± 12.1 years; 84.4% of pts were anti-TNF-naïve. Baseline PROMIS domain scores indicated notable impairment. By wk 14, improvements from baseline were observed in all 7 measured domains, with ≥5-point improvements in 4/7 domains. The median time to achieve the first ≥2-point decrease in PROMIS PI-SF T-score (n = 56/64 pts) was 12 days (95% CI, 6-13). At wk 14, 37.5% (24/64) and 7.8% (5/64) pts achieved SIBDQ improvement and remission, respectively. One pt had serious adverse events of appendicitis and diverticulitis, and another pt had a fatal event; none were related to VDZ tx. Conclusion: This IA shows an early improvement across multiple symptom domains and in pts with CD starting VDZ tx. Time to first ≥2-point decrease in PROMIS PI-SF T-score was short, with a benefit observed after 12 days from VDZ initiation. Study recruitment with a planned sample size of 200 VDZ patients and a comparator group of 100 anti-IL-23 pts) and data collection are ongoing.