A New Monoclonal Antibody-Based Biosimilar GnRH Antagonist

GHR106 is a monoclonal antibody generated against an oligopeptide corresponding to that in the extra cellular domains of human GnRH receptor. The humanized forms of GHR106 exhibit almost identical biological properties to those of decapeptide GnRH antagonists such as Antide and Cetrorelix. The Fc region of humanized GHR106 has been replaced with IgG4 subtype to eliminate activities of effector function. Therefore, the newly humanized GHR106-IgG4Fc can be used clinically as biosimilar GnRH antagonists of higher molecular size, and longer half-life (hrs. vs. days) for therapeutic treatments of fertility-related health conditions without complications arising from the effector functions of immunoglobulins.