Two biotechnology firms reported indications that a single dose of their developmental anthrax vaccine could confer immunity to the deadly terrorism agent.
Currently, the only anthrax vaccination authorized for use in the United States must be delivered over several months, in a course of five shots.
Pfenex in California and Immunovaccine in Nova Scotia, though, said a single dose of their proprietary vaccine prompted an immune response in rabbits within 28 days.
The response "persisted until at least day 70 when animals were exposed to the disease agent," the companies said in a joint statement.
"All animals vaccinated with a single dose of mrPA - DepoVax containing as little as one third of a microgram of antigen were protected from anthrax infection," the firms added.