Clinical Characteristics and Treatment Patterns of Psoriasis in Asia and Switzerland: Results of the Multicentre Global Healthcare Study on Psoriasis (GHSP)

Background: Psoriasis is a chronic inflammatory skin and systemic disease with a wide range of clinical manifestations and treatment options, including topicals, phototherapy, non-biologic systemic treatments, and biologics. Understanding regional differences in clinical characteristics and treatment patterns can help improve equity and access to care globally. Methods: The Global Healthcare Study on Psoriasis (GHSP) is an ongoing multinational, multicenter, longitudinal observational study. This study included cross-sectional data from 1415 patients across Singapore, China, Thailand, the Philippines, and Switzerland, collected between January 2020 and March 2024 using a 48-item questionnaire assessing clinical characteristics, comorbidities, disease severity, quality of life, and treatment patterns. Results: Plaque psoriasis was the predominant phenotype (90.5%). Mean Psoriasis Area and Severity Index (PASI) and Dermatology Life Quality Index (DLQI) scores were highest in China and the Philippines. Topical therapy was the most adopted treatment modality in both Asia (79.8%) and Switzerland (96.7%). Phototherapy usage was highest in Switzerland (59.0%) and Singapore (65.4%). Non-biologic systemic agents were more frequently prescribed in Switzerland (64.0%), Singapore (63.2%), and Thailand (84.7%) than in China (20.0%) and the Philippines (29.1%). Methotrexate was the predominant non-biologic except in China, where retinoids predominated. Biologic uptake was highest in Switzerland (59.5%) and Singapore (31.6%) and limited elsewhere by affordability, availability, and preference. Interleukin-17A inhibitors were the most prescribed class. Biosimilar use was low (3.0%). Conclusions: Our analysis revealed marked disparities in access to biologic treatment and reiterates the need to improve availability and affordability, through greater adoption of biosimilars and enhanced financial support.