P0720 Cost-effectiveness of vedolizumab vs. ustekinumab as first-line biologic in treatment sequencing for ulcerative colitis in Canada
Authors: Kao K E , Zhou J Y , Mac S , Martin M , Johnston K , Marshall J K 
Published: January 2025

Abstract

Background
Vedolizumab and ustekinumab are biologic therapies indicated for adult patients with moderately to severely active ulcerative colitis (UC). Multiple factors can determine the choice of first-line biologic including response/remission rate, discontinuation rates, safety profile and treatment costs. An economic evaluation can be used to synthesize evidence to identify the optimal treatment sequences to maximize clinical and economic outcomes. The objective was to evaluate the cost-effectiveness of vedolizumab followed by ustekinumab vs. ustekinumab followed by vedolizumab for adult patients with UC who are anti-tumor necrosis factor (TNF)-naïve from a societal perspective in Canada.

Methods
A Markov model estimated the cost-effectiveness of two sequences for adult patients with UC who are anti-TNF-naïve: vedolizumab as first-line biologic followed by ustekinumab vs. first-line ustekinumab followed by vedolizumab. For both sequences, patients were assumed to receive adalimumab, infliximab, or tofacitinib as a third-line option with surgery available after failing the third-line treatment. Treatment effectiveness (response, remission, discontinuation, and safety profile) was informed by a de novo network meta-analysis.1 Since effectiveness data by treatment line were unavailable, treatment effectiveness was assumed to diminish by 10% for all subsequent therapy lines based on expert opinion.2,3 Treatment costs were informed by IQVIA DeltaPA List Prices, Ontario Drug Benefit Formulary, and recent Canada’s Drug Agency health technology assessments (HTAs). A clinical expert was consulted to ensure alignment with real-world practices. Utilities were informed by published literature and previous HTAs. A lifetime time horizon was taken, with costs and outcomes discounted at 1.5%. Probabilistic base-case analyses (n = 3,000) reported total costs (2024 Canadian dollars) and quality-adjusted life-years (QALYs). Scenario analyses explored the impact of different assumptions.

Results
The vedolizumab-first sequence resulted in an incremental gain of 0.013 QALYs (12.791 vs. 12.778) and saved $157 ($291,529 vs. $291,686). Patients remained on first-line biologic longer with the vedolizumab-first sequence due to a lower discontinuation rate. The vedolizumab-first sequence remains dominant if treatment effectiveness at later lines is assumed consistent with first-line, from a payer perspective and varying time horizons.

Conclusion
From this model, a vedolizumab-first treatment sequence was dominant resulting in incremental clinical benefit, and cost savings from a societal perspective, suggesting that this treatment strategy provides better value for anti-TNF-naïve patients with moderate-to-severe UC in Canada.

References
1.Jiang J, Wojtowicz AM, Sanni O, Uyei J, Jin H, Lindsley K, et al. S1149 Comparative Efficacy and Safety of Subcutaneous Vedolizumab versus Other Targeted Inflammatory Bowel Disease Therapies in Patients With Moderate to Severe Ulcerative Colitis: A Network Meta-Analysis. Official journal of the American College of Gastroenterology | ACG. 2024 Oct;119(10S):S816.
2.Das R, Steinhart AH. Choosing Therapies in Ulcerative Colitis. Journal of the Canadian Association of Gastroenterology. 2023;7(1):9-21.
3.Lu X, Jarrett J, Sadler S, Tan M, Dennis J, Jairath V. Comparative efficacy of advanced treatments in biologic-naïve or biologic-experienced patients with ulcerative colitis: a systematic review and network meta-analysis. Int J Clin Pharm. 2023;45(2):330-341.