US Patent 10457749 Methods of purifying bispecific antibodies

The invention relates to the purification of bispecific antibodies carrying a different specificity for each binding site of the immunoglobulin molecule from a mixture of monospecific antibodies. The bispecific antibodies are composed of a single heavy chain and two different light chains, one containing a Kappa constant domain and the other a Lambda constant domain. This invention in particular relates to the isolation of these bispecific antibodies from mixtures that contain monospecific antibodies having two Kappa light chains or portions thereof and monospecific antibodies having two Lambda light chains or portions thereof. The invention also provides the methods of efficiently purifying these bispecific antibodies.