Treatment patterns and healthcare resource utilization in palmoplantar pustulosis patients in Japan: A claims database study

Background: Palmoplantar pustulosis (PPP) is a chronic, relapsing, inflammatory autoimmune condition, characterized by sterile pustules on the palms and soles. The treatment patterns of PPP and total health care resource utilization in Japan are not well described. Investigating these areas is needed to understand current PPP management in Japan. Objective: To describe the characteristics, medication treatment and health care resource utilization patterns, and associated costs of PPP patients in Japan. Methods: A retrospective analysis of insurance claims data was conducted using the Japan Medical Data Center database. Adult Patients with at least two claims with a PPP diagnosis from January 1, 2011 to March 30, 2017 and six months of follow-up after the first diagnosis were included. Patient characteristics described include age, gender, and comorbid conditions. Treatment patterns assessed include the types of treatment, sequence of treatment, and rates of discontinuation, switching, persistence and use of concomitant medications. Results: A total of 5,162 adult patients met all inclusion criteria. Mean (SD) patient age was 49.7 (11.6) years and 43.2% were male. A total of 2441 patients (47.8%) received systemic non-biologic drugs during the entire follow up period, 2,366 (46.4%) were prescribed topical therapy, 273 (5.4%) were prescribed phototherapy, while 18 (0.4%) of patients with other autoimmune comorbidities were eligible for prescribed biologics. For treatment-naïve patients with mild PPP, topical therapy was most commonly (77.1%) prescribed, whereas in moderate to severe cases of PPP, systemic non-biologic drugs (65%) were most often used. The frequency of switching was similar (64.3% to 75.3%) across various therapies and treatment lines. Conclusion: This study describes the treatment patterns and health care resource utilization for Japanese PPP patients using a large claims database, and highlights an unmet need to derive better treatment strategies for PPP and address disease burden in Japan.