Cost-effectiveness of tacrolimus ointment vs. standard treatment in patients with moderate and severe atopic dermatitis: a health-economic model simulation based on a patient survey and clinical trial data.

BACKGROUND

Atopic dermatitis (AD) affects health and quality of life (QoL) and also has great impact on both healthcare costs and costs to society.

OBJECTIVES

The aim of the study was to analyse the cost-effectiveness of treatment with tacrolimus ointment vs. standard treatment in patients with moderate to severe AD.

METHODS

A Markov simulation model was constructed capturing several key features of AD and its treatment: disease severity, treatment alternatives, and QoL. The model was populated with data from three sources: (i) efficacy data from a randomized controlled trial including patients with moderate to severe AD treated with either tacrolimus ointment or standard treatment (corticosteroids), (ii) resource utilization and QoL data from a patient survey including 161 Swedish patients with AD, and (iii) official price lists. Costs were calculated according to disease severity for the two treatment alternatives using the perspective of the Swedish healthcare sector. Two analyses were performed, one based on the quantity of medication used in the trial and one based on the survey data. The relationship between effectiveness of tacrolimus ointment and the amount of medication used was tested in sensitivity analyses.

RESULTS

In the model simulations patients with severe AD treated with tacrolimus ointment experienced on average 4.6 more AD-free weeks per year than patients given standard treatment. The corresponding figure for patients with moderate AD was 6.5 more AD-free weeks per year. The cost-effectiveness ratios [cost per Quality Adjusted Life Year (QALY) gained] for treatment with tacrolimus ointment vs. standard treatment were 2,334 British pound for moderate AD and 3,875 British pound for severe AD when treatment patterns from the survey were assumed, and 8,269 British pound for moderate AD and 12,304 British pound for severe AD when treatment patterns from the clinical trial were assumed. The results of sensitivity analyses were all well within limits to be considered cost-effective.

CONCLUSIONS

Estimates of the incremental cost-effectiveness ratio are far below the currently discussed threshold in Sweden, corresponding to approximately 48,700 British pound per QALY gained, and equivalent thresholds in other countries. Treatment with tacrolimus ointment in patients with moderate and severe AD can therefore be considered cost-effective.