Modification of treatment-sequence model with a customizable number of treatments to better reflect contemporary and future clinical practice in moderate to severe psoriasis

Existing treatment-sequence models for psoriasis are limited by lines of treatments included. We sought to more accurately capture the patient experience with an increasing number of treatments while maintaining the complexity and transparency of current models. We adapted a standard treatment-sequence model for psoriasis with two lines of active treatments followed by best supportive care (BSC). The first line was used to model the targeted treatments for comparison (Biologic A or B). The second line was used potentially to model all treatments (excluding the first-line treatment) before BSC, termed the basket of biologics (BoB). First-line treatment and the BoB were modeled with an induction and maintenance phase. The BoB efficacy was assumed to be the average of all treatments included and the BoB annual discontinuation rate was based on the number of treatments included and their individual annual discontinuation rate. A varying number of treatments in the BoB were tested (1, 5, 10). Model inputs were from published literature. In our example, when the number of treatments in the BoB increased from 1 to 10, the annual discontinuation rate of the BoB dropped from 16.5% to 1.2%. Time on BoB increased from 4.16 to 19.16 years and the time on BSC decreased from 28.28 to 13.29 years. Total costs and quality-adjusted life years increased with an increasing number of treatments in the BoB. The properties of the BoB were simplified in order to maintain the transparency of the model. Results may differ if individual treatments in the BoB are modeled line by line. Modification with the BoB allows a greater number of treatments within the model, providing a closer reflection of clinical reality, and has implications for evaluation of the long-term cost-effectiveness of psoriasis treatments.