Cost-Effectiveness of Vedolizumab for the Management of Moderate-To-Severe Ulcerative Colitis in Thailand

Abstract

Objectives: Ulcerative colitis (UC) is a chronic remitting and disease, characterized by inflammation and ulceration in the colon and rectum. Biologic therapies have shown to be effective in inducing and maintaining remission in patients with UC, however; policy makers are conscious of the additional cost of including novel biologic treatment into national drug list. Thus, this study aims to examine the clinical and economic impact of Vedolizumab compared with Infliximab for the treatment of biologic-naïve patients with moderately-to-severely UC in Thailand. Methods: A decision analytic model was used to estimate the relevant costs and health outcomes over the patients’ lifetimes using a societal perspective. Efficacy data were obtained from a network meta-analysis while other inputs (e.g., unit costs, disease management cost, adverse-event disutilities, probability of surgery, mortality etc.) were obtained from published literature and official government website. All future costs and outcomes were discounted at a rate of 3% per annum. Outcomes of interest were lifetime costs, quality adjusted life-years (QALYs) gained, and the incremental cost-effectiveness ratio (ICER) in US ($) per QALY gained. One-way and probabilistic sensitivity analyses (PSA) were conducted to investigate the effect of parameter uncertainty. Results: Using a life-time horizon, Vedolizumab costs $65,587 per patient and yields 12.48 QALYs. Infliximab costs $66,123 per patient and yields 12.18 QALYs. Infliximab was dominated by Vedolizumab. At a willingness-to-pay (WTP) threshold of $5,806 per QALY, probabilistic sensitivity analysis revealed that Vedolizumab had a 97% probability of being cost-effective. Conclusions: Our model predicted that treatment with Vedolizumab improves QALYs and increases time in remission and response compared with Infliximab. In the context of Thailand, Vedolizumab was cost saving and dominated intervention for biologic-naïve patients with moderately to severely active UC.