Cost-effectiveness analysis of micafungin versus caspofungin for treatment of systemic Candida infections in the UK

Objective: To evaluate the cost-effectiveness of micafungin compared to caspofungin in the treatment of systemic Candida infections (SCIs) in the UK, including invasive candidiasis and candidaemia. Research design and methods: Cost-effectiveness of both echinocandin antifungal drugs was estimated using decision analysis. Response to treatment, resource utilisation, and costs in the model were derived from a phase 3, head-to-head comparative trial. The model includes only data directly related to the treatment of the systemic Candida infection over the study duration (a maximum period of 14 weeks). Transition probabilities were calculated based on the efficacy results from the clinical trial. Main outcome measures: The model's effectiveness outcome is surviving patients who are successfully treated, based on the absence of signs and symptoms, radiographic abnormalities, and culture/histologic evidence associated with the fungal infection. In addition, subgroup analyses were performed to identify cost-effectiveness in several specific patient groups. Results: The total medical treatment costs for the micafungin group were 29,095 pound, which is similar to the total costs for the caspofungin group (29,953) pound. In the micafungin arm 60% of the patients and in the caspofungin arm 58% of the patients were successfully treated and alive. Cost-effectiveness ratio of micafungin was 48,771 pound, and of caspofungin 52,066 pound per successfully treated patient. Because the costs are lower and the effectiveness is higher for micafungin in comparison with caspofungin, micafungin is more cost-effective than caspofungin. However, probabilistic sensitivity and subgroup analysis show that the differences cannot be considered significant due to a large variance although micafungin remained the most cost-effective option throughout all but one of the sensitivity analyses. Conclusions: Costs and effects of micafungin compare to those of caspofungin in the treatment of systemic Candida infections in the UK. The results indicate that micafungin is cost-effective compared to caspofungin, although the difference was not found to be significant.