Fecha de publicación: -- Fuente: WIPO "tomato" The present invention relates to antibodies or antibody fragments binding to the human and non-humane primate transferrin receptor. The antibodies herein described can be used as agents to deliver pharmaceutical compounds in or across cells in the process of receptor mediated endocytosis and/or transcytosis. As the transferrin receptor is also present at the blood brain barrier endothelial cells, one aspect of the invention provides means and methods to increase the delivery of pharmaceutical compounds to the central nervous system.