Treating Generalized Pustular Psoriasis (GPP): Timing and Rationale for Biologic Treatment Switching—A Japanese e-Delphi Survey

Introduction: Generalized pustular psoriasis (GPP) is a chronic, inflammatory disease characterized by the sudden and recurrent development of widespread sterile pustules on the skin. The treatment of GPP includes non-biologic and biologic therapies. In Japan, biologic agents are being increasingly used as first-line treatment, with more biologics approved in Japan than in other countries. A previous secondary data-based study utilizing data in the Medical Data Vision database and the Japan Medical Data Center in Japan demonstrated heterogeneity in real-world biologic treatment patterns, with at least one switch during the follow-up period (mean n switches 3.8; mean length of follow-up 3.3 years) for approximately one third of patients with GPP treated with a biologic drug. The aim of this study was to evaluate where consensus lies among experts regarding switching biologic treatments for patients with GPP in Japan. Methods: A Delphi exercise that consists of three survey rounds was performed with ten Japanese dermatologists. Participants were asked to respond to questions related to experts’ experience with specific biologics, experience with switching, timing of switches and importance of specific criteria (drivers) when making the decision to switch. The consensus threshold was 70%. Results: Based on the results of the Delphi exercise, most experts rarely (60%) or never (20%) switch a biologic agent and only 20% switch often during acute symptoms/GPP flare driven by the short time of the flare; this result may be different during the maintenance phase. Lack of efficacy, loss of efficacy due to long-term use, side effects, contraindications, new products with better efficacy and safety evidence, risk of infection, and lack of adherence play an important role in making the decision to switch. Conclusion: Switches may occur for patients on biologics when flares occur (loss of effectiveness) or when there is insufficient response (lack of effectiveness). The decision to switch a biologic is impacted by several other criteria, including safety and the availability of more efficacious and better tolerated therapies. Overall, there is still an unmet need for robust evidence to inform GPP treatment choice.