General Information

Abthrax (raxibacumab) is a monoclonal antibody that neutralizes toxins produced by B. anthracis that can cause massive and irreversible tissue injury and death.

Abthrax is specifically approved for the treatment inhalational anthrax and the prevention of inhalational anthrax when alternative therapies are not available or not appropriate.

Abthrax is supplied as a solution for injection.

Clinical Results

FDA Approval
Abthrax was approved under the FDA’s Animal Efficacy Rule, which allows efficacy findings from adequate and well-controlled animal studies to support FDA approval when it is not feasible or ethical to conduct trials in humans. Efficacy was demonstrated in one study in monkeys and three studies in rabbits. All animals were administered aerosolized B. anthracis spores, and efficacy was determined by survival at the end of the studies. Animals received varying doses of raxibacumab, placebo or antibiotics normally used to treat anthrax. More animals treated with raxibacumab lived compared to animals treated with placebo. Sixty-four percent of animals in the monkey study and 44% of animals in one rabbit study receiving the 40 milligrams per kilogram dose of raxibacumab survived exposure to anthrax, compared with none in the placebo groups. All surviving animals developed toxin-neutralizing antibodies. Another study in rabbits showed that 82% of animals treated with antibiotics and raxibacumab survived exposure to anthrax compared with 65% of animals receiving antibiotic treatment alone.
The safety of raxibacumab was evaluated in 326 healthy human volunteers.

Side Effects

Adverse effects associated with the use of raxibacumab may include, but are not limited to, the following:

• rash
• extremity pain
• itching

Mechanism of Action

Raxibacumab is a monoclonal antibody that neutralizes toxins produced by B. anthracis that can cause massive and irreversible tissue injury and death. A monoclonal antibody is a protein that closely resembles a human antibody that identifies and neutralizes foreign material like bacteria and viruses.

Additional Information

For additional information regarding Abthrax or anthrax infection, please visit the GlaxoSmithKline web page.