Patent attributes
Anti-CD40 antibodies have not been reported to induce hemostatic events in patients, however elevations in pancreatic enzymes in B cell lymphoma patients receiving the anti-CD40 Ab Chir12.12 and the possible risk of pancreatitis precludes the use of this Fc-competent anti-CD40 antibody in chronic autoimmune disease and transplantation for safety reasons. We therefore generated Fc-silent IgG1 anti-CD40 antibodies (mAb1, mAb2 and mAb3) unable to mediate antibody-dependent cellular cytotoxicity (ADCC) or complement-dependent cytotoxicity (CDC) both in vitro and in vivo. mAb1 was able to prolong non-human primate renal allograft survival in combination with sub-therapeutic doses of cyclosporine. In addition, mAb1 was able to completely suppress primary and secondary antibody responses to immunization with a T cell-dependent antigen. Crucially, there was no evidence of hemostatic events or abnormal pancreatic histology in either the transplant or immunization study. Collectively these results suggest mAb1 would be a safe and efficacious therapeutic, and could be used to treat patients suffering from B lymphocyte and antigen presenting cell driven autoimmune disease or undergoing allograft transplant where CD4O-CD154 interactions are involved in contributing to pathology.
