Background Scalp psoriasis is a difficult to treat and usually chronic manifestation of psoriasis. The CalePso study showed that CPS (Clobex® Shampoo) in maintenance therapy of scalp psoriasis (twice weekly) significantly increases the probability of keeping patient under remission during 6 months, compared with vehicle (40.3% relapses vs. 11.6% relapses, ITT).
Objective The objective of the study was to assess the cost-effectiveness of a maintenance therapy with CPS vs. its vehicle in nine European countries.
Methods A 24-week decision tree model was developed with 4-weekly time steps. The considered population has moderate scalp psoriasis successfully treated with a daily application of CPS up to 4 weeks. Data were taken from the CalePso study and from national experts’ recommendations for alternative treatment choices, with their probabilities of success taken from literature to develop country-specific models. Health benefits are measured in disease-free days (DFD). The economic analysis includes drug and physician costs. A probabilistic sensitivity analysis (PrSA) assesses the uncertainty of the model.
Results Depending on the country, the mean total number of DFDs per patient is 21–42% higher with CPS compared with vehicle, and the mean total cost is 11–31% lower. The mean costs per DFD are 30–46% lower with CPS compared with the vehicle. The PrSA showed in 1000 simulations that CPS is more effective vs. vehicle in 100% of the cases and less expensive than its vehicle in 80–99% of the cases.
Conclusion This model suggests that CPS is cost-effective in maintaining the success achieved in moderate scalp psoriasis patients.