VAP-1, promotes leukocyte adhesion and transmigration through vascular walls, and generates reactive oxygen species via its oxidase activity, contributing to tissue damage and fibrosis. Timolumab’s dual inhibition of VAP-1’s adhesive and enzymatic functions aims to dampen chronic inflammation and slow disease progression in conditions driven by leukocyte-mediated injury. Its IgG4 isotype minimizes Fc effector functions, focusing on pathway blockade.