Anthrax is a highly contagious and potentially fatal human disease caused by Bacillus anthracis, an aerobic, Gram-positive, spore-forming rod-shaped bacterium with worldwide distribution as a
zoonotic infection in herbivore animals. Bioterrorist attacks with inhalational
anthrax have prompted the development of more effective treatments.
Antibodies against
anthrax toxin have been shown to decrease mortality in animal studies.
Raxibacumab is a recombinant human
monoclonal antibody developed against inhalational
anthrax. The
drug received approval after human studies showed its safety and animal studies demonstrated its efficacy for treatment as well as prophylaxis against inhalational
anthrax. It works by preventing binding of the protective
antigen component of the
anthrax toxin to its receptors in host cells, thereby blocking the toxin's deleterious effects. Recently updated
therapy guidelines for Bacillus anthracis recommend the use of
antitoxin treatment.
Raxibacumab is the first monoclonal
antitoxin antibody made available that can be used with the
antibiotics recommended for treatment of the disease. When exposure is suspected,
raxibacumab should be given with
anthrax vaccination to augment immunity.
Raxibacumab provides additional protection against inhalational
anthrax via a mechanism different from that of either
antibiotics or active immunization. In combination with currently available and recommended
therapies,
raxibacumab should reduce the morbidity and mortality of inhalational
anthrax.