Treatment Status for Generalized Pustular Psoriasis in Japanese Patients: A Retrospective Chart Review

Introduction: Generalized pustular psoriasis (GPP) is a rare, severe, and chronic inflammatory skin disease characterized by widespread pustules that leads to unpredictable and potentially serious disease flares. Information regarding treatment status for GPP and treatment patterns for flares is important but limited as a result of the rarity of the condition. We conducted a 10-year, retrospective, longitudinal chart review of treatment patterns at GPP referral hospitals in Japan. Methods: Eligible patients with GPP had at least 6 months of continuous observation data within 10 years after the date of protocol approval. Data were collected from patient records and annual patient reports. Patient characteristics and treatment details, including in relation to flare occurrence, were analyzed. Results: The median age of patients (N = 205) was 53 years; 48.3% were female and most had mild or moderate GPP (66.8%). Patients commonly received nonbiologic systemic therapy (86.3%) and a similar proportion received biologics (79.5%); 95.1% received topical treatment and 22.4% received systemic adrenal corticosteroids. Use of nonbiologic systemic therapy decreased, and use of biologics increased, over the study period. During the observation period, the proportion of patients receiving biologic therapy increased after a flare (from 41.4% receiving biologics when flares occurred to 62.9% initiating a new biologic post flare). Conclusion: In Japanese clinical practice, the evolution of treatment practices for GPP has seen an increased use of biologic therapies over time. Biologic use was common after flares; however, some flares occurred during biologic therapy, indicating a need for improved treatment options to maintain stable disease and prevent flares.