Behçet's disease: incidence, prevalence, and real-word data on the use of biologic agents in Japan.

Background: Behçet's disease (BD) is an autoinflammatory disease that can affect multiple organs, including the gastrointestinal tract. Conventional management comprises anti-inflammatory drugs such as glucocorticoids (GCs) and/or immunomodulators that alleviate symptoms. The introduction of biological agents that target tumor necrosis factor α (TNF-α) has improved disease management. The goal of this work was to analyze the current prevalence and incidence of total BD and gastrointestinal Behçet's disease (GIBD) in Japan, and examine treatment trends, especially regarding the use of TNF-α inhibitors (TNFαi).

Methods: We performed a retrospective descriptive observational study in which BD and GIBD demographic trends, medical treatment patterns, and reported adverse events (AEs) were assessed among patients with data recorded between 2017 and 2021 in the Japan Medical Data Center Claims Database (now JMDC Inc.).

Results: Prevalence of BD and GIBD in Japan during the observation period increased at an annual rate of + 3% and + 4%, respectively, while incidence decreased by - 5% and - 2%, with a more prominent decline in confirmed GIBD cases (- 15%). Although GCs were the most common initial treatment administered, use of TNFαi for BD and GIBD management increased by + 5.6% and + 8.1%, respectively. Severe AEs (mainly pneumonia and GI-associated AEs) were reported in 40% of patients receiving TNFαi; however, a high retention rate (of up to 80%) was observed 3 years after treatment initiation.

Conclusion: The use of TNFαi for GIBD treatment has increased in Japan in recent years. Additional research is necessary to further evaluate TNFαi effectiveness in GIBD and other BD subtypes.