BACKGROUND: Clostridioides difficile infection (CDI) may result in debilitating, potentially life-threatening complications. VOS is an oral microbiome treatment approved for prevention of recurrent CDI (rCDI) following antibacterial treatment of rCDI in patients 18 years of age and older.
OBJECTIVE: To assess the budget impact of including VOS on a plan’s formulary for the prevention of rCDI from a US perspective.
METHODS: A budget-impact model was developed in Microsoft Excel. Epidemiology data and baseline recurrence risk were obtained from published literature. Reduction in risk of recurrence with VOS was obtained from the ECOSPOR III, phase 3 clinical trial. Treatment and recurrence costs were obtained from published literature. A scenario with VOS uptake was compared with a scenario of standard of care alone. VOS uptake was assumed to be 10%, 20%, 30%, and 40% for recurrences 1-4, respectively, based on market share estimates. The model estimated recurrences, deaths, and per-member per-month (PMPM) costs from a third-party payer perspective, for a hypothetical 1-million-member health plan over a 1-year horizon. Costs were reported undiscounted in 2023 US dollars. One-way sensitivity analyses and VOS uptake scenario analyses were conducted.
RESULTS: For a 1-million-member plan, an estimated 225 individuals with an initial rCDI were modeled. In the base case analysis, the introduction of VOS was estimated to avert 27 recurrences and 0.30 deaths. VOS was expected to increase pharmacy costs ($0.0820 PMPM). However, pharmacy costs, were offset by reductions in cost of recurrence (-$0.0856 PMPM), and a decrease in total costs (-$0.0035 PMPM). Cost savings were sensitive to variation in cost of recurrence, risk reduction for VOS, and baseline risk of recurrence; however, total PMPM costs did not exceed $0.03 in any parameter variation. In scenario analyses, assuming a higher uptake of VOS in first recurrence resulted in more subsequent? recurrences avoided and greater cost savings.
CONCLUSIONS: Treatment with VOS has been shown to significantly reduce recurrences for patients with rCDI compared to antibiotics alone. This study illustrates that VOS is a cost-saving treatment despite increasing pharmacy costs, due to greater reductions in recurrence costs. Furthermore, treating with VOS in earlier recurrences leads to greater cost savings. As such, VOS provides both clinical and economic value to a US health plan.
