Reducing the immunogenicity of anti-CD20 antibodies by framework patching

• Main Author: LEUNG SHAWN SHUI-ON
• Format: Patent
• Language: English
• Published: 17.02.2009
• Subjects: BEER; BIOCHEMISTRY; CHEMISTRY; COMPOSITIONS THEREOF; CULTURE MEDIA; ENZYMOLOGY; FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIREDCHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERSFROM A RACEMIC MIXTURE; HUMAN NECESSITIES; HYGIENE; MEDICAL OR VETERINARY SCIENCE; METALLURGY; MICROBIOLOGY; MICROORGANISMS OR ENZYMES; MUTATION OR GENETIC ENGINEERING; ORGANIC CHEMISTRY; PEPTIDES; PREPARATIONS FOR MEDICAL, DENTAL, OR TOILET PURPOSES; PROPAGATING, PRESERVING OR MAINTAINING MICROORGANISMS; SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS ORMEDICINAL PREPARATIONS; SPIRITS; VINEGAR; WINE

Framework (FR)-patching is a novel approach to modify immunoglobulin for reducing potential immunogenicity without significant alterations in specificity and affinity. Unlike previous described methods of humanization, which graft CDRs from a donor onto the frameworks of a single acceptor immunoglobulin, we patch segments of framework (FR1, FR2, FR3, and FR4), or FRs, to replace the corresponding FRs of the parent immunoglobulin. Free assortment of these FRs from different immunoglobulins and from different species can be mixed and matched into forming the final immunoglobulin chain. A set of criteria in the choice of these FRs to minimize or eliminate the need to reintroduce framework amino acids from the parent immunoglobulin for patching is described. The approach gives greater flexibility in the choice of framework sequences, minimizes the need to include parent framework amino acids, and, most importantly, reduces the chances of creating new T- and B-cell epitopes in the resultant immunoglobulin.