BUDGET IMPACT OF FIDAXOMICIN COMPARED WITH VANCOMYCIN FOR THE TREATMENT OF CLOSTRIDIUM DIFFICILE ASSOCIATED DIARRHEA IN THE UNITED STATES
Budget Impact of Fidaxomicin compared with Vancomycin for the treatment of Clostridium difficile associated diarrhea in the United States
Clostridium difficile–associated diarrhea (CDAD) is the leading cause of nosocomial diarrhea. In 2011, there were 453,000 new CDAD episodes resulting in 29,000 deaths in the U.S. Fidaxomicin is an antibacterial drug indicated for treatment of CDAD. Compared with vancomycin, it has a comparable clinical response and superior sustained clinical response, defined as clinical response at the end of treatment, and survival without proven or suspected CDAD recurrence through 25 days beyond the end of treatment. We present a model to evaluate the budget impact of fidaxomicin compared with vancomycin patients with CDAD in the U.S.
We developed a decision-analytic model to simulate the natural history of CDAD among a cohort of 1000 patients. In the model, we followed patients with CDAD for a period of 25 days post-treatment and evaluated the annual budget impact of fidaxomicin compared with vancomycin using a hospital payer perspective. The probabilities of clinical response, sustained clinical response, and death were obtained from the fidaxomicin product insert. CDAD recurrence through 25 days beyond the end of treatment was calculated as persons who did not have a sustained clinical response, death, or a clinical failure. Wholesale acquisition cost of vancomycin was obtained from the analysource.com database. Cost estimates of CDAD were obtained from the literature and indexed to 2015 cost figures using CPI medical inflation data. We then projected clinical response, sustained clinical response, and the threshold price at which fidaxomicin would be cost-neutral.
The model predicted that among the 1000 patients treated, 880 patients achieved clinical response in the fidaxomicin arm compared with 865 patients in the vancomycin arm (Figure 1). 709 patients obtained sustained clinical response through 25 days post-treatment in the fidaxomicin arm, compared with 570 patients in the vancomycin arm. The threshold price below which fidaxomicin was cost-saving was $202.
Based on the decision-analytic model, fidaxomicin has the potential to be cost-saving from a hospital payer perspective.
Figure 1: Estimated number of patients in various health states at 25 days post-treatment