Budget Impact Analysis of Fidaxomicin Versus Vancomycin for the Treatment of Clostridioides difficile Infection in the United States

Introduction Fidaxomicin is as effective as vancomycin in treating Clostridioides difficile infection (CDI) but more effective at preventing recurrence. However, because fidaxomicin is more costly than vancomycin, its overall value in managing CDI is not well understood. This study assessed the budget impact of introducing fidaxomicin versus vancomycin for the treatment of adults with CDI from a hospital perspective in the US. Methods A cohort-based decision analytic model was developed over a 1-year horizon. A hospital with 10,000 annual hospitalizations was simulated. The model considered two adult populations: patients with no prior CDI episode and patients with one prior CDI episode. Two scenarios were assessed per population: 15% fidaxomicin/85% vancomycin use and 100% vancomycin use. Model inputs were obtained from published sources and expert opinion. Model outcomes included cost, payment, and revenue at the hospital level, per treated CDI patient, and per admitted patient. Budget impact was calculated as the difference in revenue between scenarios. One-way sensitivity analyses tested the effects of varying model inputs on the budget impact. Results In patients with no prior CDI episode, treatment with fidaxomicin resulted in potential savings over 1 year of $1105 at the hospital level, $14 per treated CDI patient, and $0.11 per admitted patient. In patients with one prior CDI episode, fidaxomicin use was associated with potential savings over 1 year of $1150 at the hospital level, $74 per treated CDI patient, and $0.12 per admitted patient. Savings were driven by a reduced rate of CDI recurrence with fidaxomicin treatment and uptake of fidaxomicin. Sensitivity analyses indicated savings when inputs were varied in most scenarios. Conclusion Budgetary savings can be achieved with fidaxomicin due to reduced CDI recurrence as a result of a superior sustained clinical response. Our results support considering the broader benefits of fidaxomicin, beyond its cost, when making formulary inclusion decisions. Plain Language Summary Clostridioides difficile infection (CDI) is a common hospital-acquired infection that affects about half a million people in the US each year. In some patients who have already had CDI, it can recur. These recurrent infections can be difficult to treat, and they place a burden on the healthcare system. CDI is usually treated with the antibiotics fidaxomicin or vancomycin. Fidaxomicin is as effective as vancomycin for treating CDI but is even more effective than vancomycin at preventing CDI recurrence. However, fidaxomicin is more expensive. In this study, we estimated the impact of replacing vancomycin with fidaxomicin for treating CDI on the budget of a typical US hospital. We estimated that treating 15% of patients with CDI using fidaxomicin in place of vancomycin would save the hospital between $1105 and $1150 in a year. This means that despite the higher cost of fidaxomicin, treating as few as 15% of patients with CDI using fidaxomicin instead of vancomycin can be cost-saving for hospitals.