Abstract
Background
Intravenous vedolizumab (VDZ IV) is approved for the treatment of moderately to severely active ulcerative colitis (UC). Subcutaneous VDZ (VDZ SC) was studied in the VISIBLE 1 trial (NCT02611830) and is under review by the US Food and Drug Administration for maintenance treatment. VARSITY (NCT02497469) is the first head-to-head trial to compare 2 biologics (VDZ IV vs. adalimumab SC [ADA]) in UC. We evaluated the cost-effectiveness of VDZ SC vs. ADA from a US payor perspective using efficacy data from these trials.
Methods
We used a cohort decision tree model with a time horizon up to 2 years. Simulated cohorts included patients with and without prior biologic therapy who initiated treatment with VDZ IV (300 mg in weeks 0, 2, and 6) or ADA (day 1: 160 mg; day 15: 80 mg) for a 6 week induction period. Initial responders went on to maintenance treatment with VDZ SC (108 mg every 2 weeks) or ADA (40 mg every 2 weeks); maintenance remitters continued treatment for 2 years. Patients with inadequate response to induction, or serious adverse drug reaction (ADR) switched to treatment with biologics (tofacitinib, infliximab, or golimumab). Patients who were intolerant to biologics received corticosteroids with or without curative surgery. The relative effectiveness of VDZ IV vs. ADA was derived from network meta-analyses of published randomised controlled trials. Model outcomes included total direct medical costs associated with drug acquisition, administration, routine monitoring, toxicity management, ADRs, and cost per remission achieved. Costs (eg, drug, monitoring, healthcare resource utilisation, administration) are expressed in 2019 US$.
Results
Based on our model, VDZ SC was associated with greater clinical response (52.92% vs. 45.07%) and remission at year 2 (22.49% vs. 14.36%) compared with ADA. Total direct medical costs per patient over 2 years were $98,034 for VDZ SC and $137,007 for ADA. After 2 years of treatment, more patients were in remission with VDZ SC than ADA for lower overall costs.
Conclusion
The clinical foundation for this model is built primarily on evidence from clinical trials of adults with moderately to severely active UC. This allowed us to extrapolate clinical outcomes out to 2 years and estimate direct medical costs over that time. These modelled outcomes indicated that treatment with VDZ IV followed by VDZ SC is more effective and less costly for remission compared with initiation with ADA.
Four-Year Maintenance Treatment With Adalimumab in Patients with Moderately to Severely Active Ulcerative Colitis: Data from ULTRA 1, 2, and 3