OBJECTIVES: To evaluate the cost and utility of calcipotriol/bethamethasone (Dovobet) compared to calcipotriol (Dovonex) in the treatment of psoriasis vulgaris. METHODS: A four-state Markov model was designed to estimate the cost and utilities associated with psoriasis treatment over a full year. The model consists of 4 mutually exclusive health states: Controlled psoriasis, and three states of uncontrolled psoriasis: Initial treatment, subsequent treatment, and no treatment. Various sources were used to estimate the parameters of the model, but the primary source for utility scores and transition probabilities was an international phase III trial, estimating efficacy and the quality of life for 737 patients randomised to one of four different treatment options. Among the treatment options were calcipotriol/bethamethasone (Dovobet) once daily and the currently most frequently prescribed topical antipsoriatic in the UK, calcipotriol (Dovonex). RESULTS: In the baseline model, the average annual cost to the NHS associated with treatment of a psoriasis patient with calcipotriol/bethamethasone (Dovobet) once daily amounted to £64.7. The cost of calcipotriol twice-daily treatment in the same period would amount to £120.3. In terms of number of QALYs gained in a year, calcipotriol/bethamethasone (Dovobet) once daily patients on average accumulated 0.7719 QALYs, compared to calcipotriol twice daily patients who accumulated only 0.7599 QALYs. Thus, in the baseline model treatment with calcipotriol/bethamethasone (Dovobet) twice daily is both less costly and more effective than the current standard therapy of calcipotriol twice daily. These results were robust to extensive sensitivity analysis of important assumptions. CONCLUSION: Looking at a full year of treatment, the cost-utility analysis showed that calcipotriol/bethamethasone (Dovobet) once daily was both less expensive and yielded more QALYs than the current standard therapy (calcipotriol).