OBJECTIVES: There is little clinical consensus on the treatment of recurrent Clostridium difficile infections (CDI). As such, this study was conducted to evaluate the cost-effectiveness of three medical regimens, including novel therapies, for the first recurrence of CDI.

METHODS: A decision tree model was created to compare three possible treatment options for patients with a first recurrence of CDI: oral vancomycin alone, fidaxomicin alone, or bezlotoxumab plus vancomycin. The model was performed from the payer’s perspective with a time horizon of 1 year using a 3% discount rate. Only direct costs were used. Subsequent treatment failures and recurrences were included in the model. Systematic review of literature was performed to identify clinical, utility, and cost data. Quality adjusted life years (QALY) and incremental cost-effectiveness ratios (ICER) were calculated. Willingness-to-pay (WTP) threshold was set at $50,000 / QALY gained. Model’s robustness was tested using one-way sensitivity analyses and probabilistic sensitivity analysis (PSA).

RESULTS: Vancomycin was associated with the lowest cost ($16,157) and a 0.8007 QALY gain. Fidaxomicin led to a higher QALY (0.8046), at a cost of $17,047. The ICER for fidaxomicin compared to vancomycin was $226,903 / QALY. Bezlotoxumab plus vancomycin was a dominated strategy with a QALY gained lower than fidaxomicin (0.8029) despite higher cost ($18,939). Both one-way sensitivity analyses and PSA illustrated that parameter uncertainty was unlikely to alter the model’s findings.

CONCLUSIONS: Vancomycin alone appears to be the most cost-effective regimen for the treatment of first recurrence of CDI. Fidaxomicin alone led to the highest QALY gained, but at a cost beyond what is customarily considered cost-effective. Bezlotoxumab plus vancomycin was dominated, and unlikely to be cost-effective. Results may be limited by the reliance on randomized control studies for the clinical information needed.