Nonhuman primates were recently protected against Lassa fever by using three types of monoclonal antibodies eight days after they became infected with the virus, according to a study conducted by researchers at the University of Texas Medical Branch at Galveston (UTMB).
While the virus is known to infect hundreds of thousands of people per year worldwide, killing approximately 34 percent of those infected, there are no treatments or vaccines approved by the U.S. Food and Drug Administration (FDA).
The virus is classified as a Category A pathogen by the U.S. government, which poses the highest risk to public health, for its ability to be synthesized into a bioweapon
Thomas Geisbert, professor in UTMB’s Department of Microbiology and Immunology, said the study tested a combination of three monoclonal antibodies by giving them to nonhuman primates beginning up to eight days following exposure to a lethal amount of the Lassa virus.
“We found that the treatments were well-tolerated and provided 100 percent protection from Lassa fever,” Geisbert said. “Without treatment, the animals show evidence of the virus in their bodies by day four after exposure.”
Widely used to treat a variety of autoimmune diseases and cancers, monoclonal antibodies have been utilized by medical researchers and practitioners since at least the 1980’s. Currently, more than 45 types are approved for use by the U.S. Food and Drug Administration (FDA) and the European Medicines Agency.
“The fact that the treatment was able to rescue 100 percent of the animals more than a week after infection with Lassa virus suggests that this therapy may benefit patients with Lassa fever in West Africa, who often arrive at the clinic at a late stage of disease,” Tulane researcher Robert Garry said.
He continued, stating that the research team was accelerating further development so that the promising treatment can be introduced into clinics in West Africa and deployed as a deterrent against the use of Lassa virus as a bioweapon.