Raxibacumab (ABthrax) is a human IgG1 monoclonal antibody against Bacillus 
anthracis protective antigen. HGS is currently providing stockpiles of the agent 
to the US government for use in the prevention and treatment of inhalation 
anthrax. As of May 2009, the candidate was undergoing review by the US Food and 
Drug Administration. The availability of bioterrorism countermeasures has become 
more important since the September 2001 anthrax attacks, and development of 
raxibacumab is a significant advance in this area.