Brolucizumab is an active substance from the group of VEGF inhibitors. The monoclonal antibody (MAK) is a humanised single-chain antibody fragment with a single Fv chain. The antibody belongs to the group of vascular endothelial growth factor inhibitors (VEGF inhibitors). VEGF is a group of proteins from different groups that act as signalling molecules and perform different tasks in human vascular tissues.
VEGF-A is important for angiogenesis (formation of new vessels) in the eye. Brolucizumab binds to all forms of VEGF-A and thus prevents the growth factor from binding to its receptor. By interrupting the VEGF/VEGFR signalling cascade, the formation of new retinal vessels and the development of retinal oedema is reduced. Brolucizumab has a low molecular weight of only 26 kilodaltons (kDa), which makes tissue penetration (which is of paramount importance for local application) and drug clearance particularly favourable.