A monoclonal antibody that was known to be effective against the fatal Hendra virus is now known to protect against the closely related Nipah virus too -- the basis of the 2011 movie "Contagion" -- a highly infectious and deadly agent that results in acute respiratory distress syndrome and encephalitis, person-to-person transmission, and greater than 90 percent case fatality rates among humans. The results of the study, conducted by a team of Federal and university scientists, will appear in Science Translational Medicine online: "Therapeutic Treatment of Nipah Virus Infection in Nonhuman Primates with a Neutralizing Human Monoclonal Antibody." The full study will be available following the release of the embargo at 2 p.m. June 25, 2014.
The collaborative research team members are from the Uniformed Services University of the Health Sciences (USU), the University of Texas Medical Branch (UTMB) and Galveston National Laboratory (GNL), the National Institutes of Health (NIH''s) National Institute of Allergy and Infectious Diseases (NIAID) and Rocky Mountain Laboratories (RML), and the National Cancer Institute (NCI), NIH.
Nipah virus and the closely related Hendra virus are naturally found in Pteropid fruit bats (flying foxes). They are considered emerging viruses and are capable of causing severe illness and death in a variety of domestic animals and humans.
In experiments carried out in non-human primates at the GNL in Galveston, Texas, where there is a high-containment facility for working with live Nipah virus, the team of researchers, under the direction of Thomas W. Geisbert, Ph.D., professor, in the Department of Microbiology, UTMB and study corresponding author, demonstrated that administering a human monoclonal antibody therapy after exposure to Nipah virus protected the animals from disease.
"Previously, our team showed that this same antibody therapy could protect nonhuman primates from a deadly Hendra virus infection, but here we have shown for the very first time, that not only does this antibody protect against Nipah virus infection, but remarkably can do so even when given the therapy much later after infection and when the animals show clinical signs of disease. What this means is that as far as people are concerned these latest findings strongly suggest that a real potential treatment for Nipah virus infection is at hand," said Christopher C. Broder, Ph.D., professor of Microbiology at USU and also study corresponding author.
It was earlier work at USU and NCI, supported by NIAID that isolated and characterized the monoclonal antibody known as m102.4. The antibody attacks a critical component of Nipah and Hendra viruses and blocks their ability to infect cells. Antibodies - proteins found in blood or other bodily fluids of vertebrates - are used by the immune system to identify and neutralize viruses and bacteria.
"This recent success of the antibody therapy against Nipah virus disease in a nonhuman primate is a key step towards its development as a therapeutic for use in people," according to Dr. Geisbert.
"There are no other effective therapeutic options for Nipah virus infection," according to Dr. Broder. "Indeed, because of data now reported here, and from our previous work with this antibody in Hendra virus experiments, there was sufficient interest for the Queensland government in Australia to initiate a phase I clinical safety trial with m102.4 that is set to commence later this year."
Nipah virus and Hendra virus, members of the paramyxovirus family, are highly infectious agents that emerged from flying foxes in the 1990s to cause serious disease outbreaks in humans and livestock in Australia, Malaysia, Singapore, Bangladesh and India.
"There are currently no licensed and approved vaccines or therapeutics for prevention and treatment of disease caused by these viruses for humans or livestock," said Dr. Geisbert. "This human monoclonal antibody is the first effective antiviral drug against Nipah virus and Hendra virus that has a real potential for human therapeutic applications."
The human monoclonal antibody, m102.4, is protected under issued and pending patents in many countries around the world.