BACKGROUND: Vedolizumab (VDZ) is a biological therapy approved in the United States (U.S.) for the treatment of moderately to severely active ulcerative colitis (UC) and Crohn’s disease (CD).
OBJECTIVE: To assess the 5-year impact on budget and clinical outcomes of adding VDZ to a health plan’s formulary in the U.S. for adults with moderately to severely active UC or CD.
METHODS: An Excel-based model was developed to estimate the annual impact on costs (drug, medical, total) and clinical outcomes associated with adding VDZ to a 1 million-member U.S. health plan’s formulary. Treatments included biologics (VDZ, infliximab, adalimumab, golimumab, certolizumab, and natalizumab) and conventional therapy (CT: aminosalicylates, corticosteroids, immunomodulators) approved for treatment of UC or CD. Disease prevalence was taken from the published literature and the proportion of patients receiving biologics was estimated from current market shares. One-year efficacy data (response and remission) were derived from placebo-controlled trials of approved biologics and CT using the Bucher method. Costs (wholesale acquisition drug costs and health state costs) were taken from published literature. Market mix and VDZ uptake were based on current market share and projections: VDZ uptake ranged from 5% to 16% in years 1 to 5 coming mostly from other biologics. Base case analyses assumed all patients received the standard approved dose of the biologics. Results included costs (total and per-memberper- month [PMPM]) in 2014 U.S. dollars and total clinical outcomes (patients in response/remission and surgeries). Sensitivity analyses were performed varying health state costs and efficacy for each treatment within plausible ranges.
RESULTS: The model predicted that including VDZ would result in total PMPM cost savings ranging from $0.011 (0.13%) to $0.035 (0.41%) over 5 years. PMPM drug costs increased by $0.011 to $0.032, while medical costs decreased by $0.021 to $0.067. Adding VDZ led to 38 more patients in remission, 37 more in response and 2 fewer surgeries in year 5. Annual cost savings to the health plan ranged from $200,352 to $653,797 over 5 years. Results were most sensitive to VDZ efficacy and health state costs. However, VDZ remained cost saving with all parameter variation.
CONCLUSIONS: The model suggests that the adoption of VDZ on formulary for treatment of moderately to severely active UC and CD results in overall cost savings while improving clinical outcomes.
