Unpublished data referred to in a publication of the 2018 Phase I clinical trial results of ansuvimab, reported that a single infusion of ansuvimab provided full protection of rhesus macaques and was the basis of the dosing used for human studies. Development
Ansuvimab was developed by the Vaccine Research Center with support of the United States National Institutes of Health and the Defense Advanced Projects Agency. The heavy and light chain sequences of ansuvimab mAb were cloned into CHO cell lines to enable large-scale production of antibody product for use in humans. Human safety testing
In early 2018, a Phase 1 clinical trial of ansuvimabs safety, tolerability and pharmacokinetics was conducted by Dr. Martin Gaudinski within the Vaccine Research Center Clinical Trials Program that is led by Dr. Julie E. Ledgerwood. The study was performed in the United States at the NIH Clinical Center and tested single dose infusions of ansuvimab infused over 30 minutes. The study showed that ansuvimab was safe, had minimal side effects and had a half-life of 24 days. Ridgeback Biotherapeutics
A license for ansuvimab was obtained by Ridgeback Biotherapeutics in 2018, from the National Institutes of Health-National Institute of Allergy and Infectious Diseases. Ansuvimab was given orphan drug status in May 2019 and March 2020. Experimental use in the Democratic Republic of Congo
During the 2018 Équateur province Ebola outbreak, ansuvimab was requested by the Democratic Republic of Congo (DRC) Ministry of Public Health. Ansuvimab was approved for compassionate use by the World Health Organization MEURI ethical protocol and at DRC ethics board.
The Neutralization of virus infection occurs when the Fab regions of antibodies binds to virus antigen(s) in a manner that blocks infection. Antibodies are also able to "kill" virus particles directly and/or kill  infected cells using antibody-mediated  "effector functions" such as  opsonization, complement-dependent cytotoxicity, antibody-dependent cell-mediated cytotoxicity and antibody-dependent phagocytosis. These effector functions are contained in the Fc region of antibodies, but is also dependent on binding of the Fab region to antigen. Effector functions also require the use of  complement proteins in serum or  Fc-receptor on cell membranes. Ansuvimab has been found to be capable of killing cells by antibody-dependent cell-mediated cytotoxicity. Other functional killing tests have not been performed. History
Ansuvimab is a monoclonal antibody that is being evaluated as a treatment for Ebola virus disease. Its discovery was led by the laboratory of Nancy Sullivan at the United States National Institutes of Health Vaccine Research Center and J. J. Muyembe-Tamfum from the Institut National pour la Recherche Biomedicale (INRB) in the Democratic Republic of Congo,  working in collaboration with the Institute for Biomedical Research (Bellinzona, Switzerland) and the United States Army Medical Research Institute of Infectious Diseases. Ansuvimab was isolated from the blood of a survivor of the 1995 outbreak of Ebola virus disease in Kikwit, Democratic Republic of Congo roughly ten years later.In 2018, a Phase 1 clinical trial of ansuvimab was conducted by Martin Gaudinski within the Vaccine Research Center Clinical Trials Program that is led by Julie E. Ledgerwood.