The bavituximab drug was tested on lab animals and it has shown remarkable success in tackling two viruses, including a close cousin to the bioterror pathogen, a recent study announces. This kind of virus is notorious for mutations that evade or resists conventional pharmaceutical molecules but, instead of confronting the intruder head-on, bavituximab waits until the virus has infected the cell. At that point, a fatty molecule called phosphatidylserine, which is positioned on the cell wall’s internal surface, flips to the outside of the cell. The drug then latches onto the phosphatidylserine, sending a signal to the body’s immune system to dispatch white blood cells to destroy the infected cell.

In a study in Nature Medicine, bavituximab was put through its pace among guinea pigs infected with Pichinde virus, a close relative to the Lassa fever virus, considered a potential bioterror weapon by the Pentagon. The study revealed that the animals that were not inoculated with bavituximab were all killed and those who had received the injection had a 50-percent survival rate. This rose to 63 percent if the bavituximab group received an additional injection with a standard anti-virus drug called ribavirin. Furthermore, the drug also provided 100% protection amongst mice exposed to a virus called cytomegalovirus (CMV), whereas only 25% percent of the untreated animals survived.

Bavituximab, a monoclonal antibody, is currently in clinical trials by Peregrine Pharmaceuticals of California to treat patients with hepatitis C. Previous research has shown that phosphatidylserine-flipping occurs in cells infected with influenza, the herpes simplex virus, viruses in the families of the smallpox and rabies viruses as well as HIV. Co-author of this study, Philip Thorpe, told the media that the findings are exciting, raising the prospect of a completely new class of anti-viral drugs capable of solving the problem of mutation.