Comparative effectiveness and cost evaluation of Risankizumab and Adalimumab in the management of psoriasis: a real-world study in Saudi Arabia.

Background: Psoriasis, an immune-mediated chronic inflammatory disease primarily affecting skin and joints, has varying prevalence rates globally. It manifests in five types, with chronic plaque psoriasis being the most common. Treatment, which has no definitive cure, aims for complete resolution of skin symptoms and depends on disease extent, severity, and impact on patients' lives. Biologics are an emerging treatment for psoriasis, targeting specific inflammatory pathways for potentially safer, more effective outcomes. However, these come with significant costs, necessitating more research to ensure value for money. This study aimed to compare the effectiveness of Risankizumab versus Adalimumab, the most commonly utilized biologic for managing psoriasis in Saudi Arabia.

Methods: This study retrospectively compared the effectiveness and direct medical cost of Risankizumab and Adalimumab in treating chronic plaque psoriasis in adults from two Saudi Arabian healthcare centers. The Psoriasis Area and Severity Index (PASI) and body surface area (BSA) were used to assess treatment effectiveness, with patient data sourced from electronic medical records. Multiple regression analysis was performed to examine various factors affecting treatment outcomes. An economic evaluation was conducted to examine the cost-effectiveness of the two drugs, considering four scenarios with varying dosage patterns and costs. Analysis was performed from the perspective of public healthcare payers and considered all utilized health services.

Results: The data for 70 patients were analyzed, with comparable baseline characteristics between groups. While Risankizumab led to a greater reduction in PASI scores and BSA affected, these results were not statistically significant. The annual treatment cost for Risankizumab was higher than Adalimumab. Various scenarios were studied, considering real acquisition costs, double dosing for Adalimumab, and the use of biosimilars. A scenario assuming double dosing for Adalimumab and a 40% discount for Risankizumab demonstrated both cost and efficacy advantages in 71.25% of cases.

Conclusions: This study compared the effectiveness and cost of Risankizumab and Adalimumab for treating chronic plaque psoriasis in Saudi Arabian hospitals. Although Risankizumab showed a greater reduction in symptoms, the difference was not statistically significant. However, under certain scenarios, Risankizumab demonstrated cost and efficacy advantages. These findings may influence treatment decisions for psoriasis, but further research is needed.