UniBody is Genmab’s proprietary antibody technology for creating a monovalent non-activating and stable antibody format with an anticipated longer therapeutic window than current small antibody formats. UniBody molecules are based on human IgG4 antibodies, and consist of only one heavy and one light chain. UniBody molecules are suitable as therapeutics when monovalent binding to the target is required and no immune effector functions are desired, for instance for the treatment of asthma, inflammation, and cardiovascular and infectious diseases.
BAC’s affinity ligands for UniBody molecules were designed to distinguish between monovalent UniBody molecules and native IgG4 antibodies, thereby avoiding binding to the Fab-domain of the UniBody. Despite the high similarity between the related proteins, BAC’s UniBody-specific affinity ligands did not show any cross-binding to other mammalian IgG4 molecules.
Dr Laurens Sierkstra, CEO of BAC said: “We are delighted to have completed the feasibility study on the custom-made CaptureSelect affinity ligands for Genmab. Besides the lack of the hinge region, some of Genmab’s monovalent UniBody molecules differ only in a few amino acids compared to the native homodimer IgG4 molecules, and the challenge was to create affinity ligands targeting those regions. This success further confirms that our CaptureSelect platform can consistently produce highly specific affinity ligands and can discriminate between proteins differing in only a few amino acids.”