The US medicines safety watchdog has approved obiltoxaximab (Anthim) for the treatment of inhalational anthrax in combination with other therapies and when other treatments are either unvailable or inappropriate.
Inhalational anthrax is a rare disease triggered by exposure to infected animals or animal products, or by exposure to anthrax spores that could occur in a bioterrorism incident.
When inhaled, anthrax bacteria replicate and produce toxins that can cause extensive tissue damage and death, according to the US Food and Drug Administration (FDA), which approved oblitoxaximab on 18 March 2016.
The decision was based on the results of animal studies, which concluded that the survival rate in animals treated with the drug was higher compared with animals given placebo. Survival rates were also higher when the drug was given as a combination therapy with antibacterial drugs.
Edward Cox, director for the Office of Antimicrobial Products in the FDA’s Center for Drug Evaluation and Research, says: “As preparedness is a cornerstone of any bioterrorism response, we are pleased to see continued efforts to develop treatments for anthrax.”
The drug, a monoclonal antibody that neutralises toxins produced by the anthrax spores, was approved under the FDA’s ‘animal rule’, which allows findings from animal studies to support drug approval when it is unfeasible or unethical to conduct trials in humans.
The product carries a warning that it can cause hypersensitivity, including anaphylaxis. But the FDA says the drug’s benefits outweigh this risk.
Oblitoxaximab was developed by Elusys Therapeutics in the United States in conjunction with the US department of health and human services. It is not approved for use in Europe.