Human Anti ECULIZUMAB

Human Anti-Eculizumab Antibody, clone AbD32107_hIgG1 is a paratope specific, inhibitory anti-idiotypic antibody that specifically recognizes the free humanized monoclonal antibody eculizumab. It does not recognize free human complement C5 or eculizumab in complex with C5. The antibody can be used to measure free eculizumab or eculizumab biosimilars in patient samples.Clone AbD32107_hIgG1 is a fully human recombinant monoclonal antibody with IgG1 isotype and is suitable as a surrogate positive control or calibrator in an anti-drug antibody (ADA) assay. A pair of anti-eculizumab antibodies can be used to develop a pharmacokinetic (PK) bridging assay to measure free drug. This antibody is recommended as the detection reagent, paired with Anti-Eculizumab Antibody clone AbD32311 (HCA312) in monovalent Fab format as the capture antibody.Eculizumab (Soliris) is a humanized IgG2/4 kappa antibody. The heavy chains are comprised of human IgG2 sequences in CH1, the hinge and the adjacent portion CH2, and human IgG4 sequences in the remaining part of CH2 and CH3. The drug is used to treat paroxysmal nocturnal hemoglobinuria (PNH), a rare acquired life-threatening disease of the blood characterized by destruction of red blood cells by the complement system. It also has approval as an orphan drug for treatment of atypical hemolytic uremic syndrome (aHUS). Eculizumab specifically binds to the terminal complement component 5 (C5) and inhibits the cleavage of C5 to C5a and C5b by the C5 convertase, which prevents the generation of the terminal complement complex C5b-9. Both C5a and C5b-9 cause the terminal complement-mediated events that are characteristic of PNH and aHUS. A 1:1 molar ratio of eculizumab to C5 is sufficient for C5 inhibition.