Definition

A recombinant human-derived monoclonal antibody targeting the tumor cell-protective protein complement factor H (CFH), with potential immunomodulatory and antineoplastic activities. Upon administration, the anti-CFH monoclonal antibody GT103 targets and binds specifically to a conformationally distinct epitope within a specific crucial functional domain of CFH bound on tumor cells. This activates the complement cascade, triggers complement dependent cytotoxicity and leads to the destruction of the tumor cells. In addition, GT103 modulates the adaptive anti-tumor immune response, thereby reducing the number of immune suppressive T-regulatory cells (Tregs) and myeloid-derived suppressor cells (MDSCs) in the tumor. This may potentially provide long-term anti-tumor immunity and protection. CFH, the major regulator of the central complement protein C3b in the alternative pathway of complement activation, normally prevents cells from destruction by the immune system. CFH may play a key role in protection against complement-mediated lysis in various cancer cells.