Backgrounds Infliximab (IFX) potently suppresses ocular attacks in Behcet’s disease (BD) with uveitis, resulting in favorable longterm visual prognosis. However, about one third of the patients had ocular attacks one or two weeks before the next IFX infusion, suggesting that the efficacy of IFX depends on the concentration. This study investigates IFX trough levels and antibody toward IFX (ATI) in BD patients receiving IFX and analyzes the relationship of the pharmacokinetics with clinical efficacy.