OBJECTIVES: Clostridium difficile (CDiff) is a common nosocomial infection, with high rates of recurrence (up to 30%). New treatments have been developed to treat recurrence. To determine the cost-effectiveness of CDiff treatments to prevent recurrence we compared bezlotoxumab (a monoclonal antibody) and three fecal microbiome transplantation (FMT) products: RBX-2660; SER-109; and CP101.

METHODS: A decision-analytic Markov model was developed to evaluate CDiff preventive recurrence treatments from a U.S. healthcare payer perspective. The population included individuals with one CDiff previous infection (64 years old). The model incorporates the risk of treatments’ mild/moderate adverse events (AE) and severe AE, incorporating efficacy, failure (recurrence) and death after treatment using 1-year time horizon. Clinical trials for the various products were used to model the health states of well (no recurrence of CDiff infection), CDiff recurrence, and death. Post-treatment infection, recurrence, AE, and hospitalization were assigned dis-utility values. Costs of CDiff preventive treatment and AEs were included. End points included costs, quality-adjusted life years (QALYs), and incremental cost‐effectiveness ratios (ICERs), and a willingness‐to‐pay (WTP) threshold of $150,000/QALY. Both probabilistic and deterministic sensitivity analyses were conducted.

RESULTS: The primary analysis found that RBX-2660 had an expected cost of $19,348 and 0.92 QALYs. Similar results were for bezlotoxumab ($19,591 and 0.93 QALYs) but SER-109 had higher costs ($25,310 and 0.95 QALYs). CP-101 was dominated because of its higher cost ($37,599) and lower QALYs (0.91). A probabilistic sensitivity analysis was conducted and bezlotoxumab had the highest probability of being cost-effective (51.8% of the simulations) using the established WTP threshold. The next best treatment was RBX-2660, with a 31% probability of being cost-effective at a WTP value of $150,000.

CONCLUSIONS: Compared to other preventive treatments for the recurrence of CDiff, RBX-2660 had the lowest cost but bezlotoxumab had the highest probability of being cost-effective at the $150,000 WTP threshold.