Treatment for inhalational anthrax wins US approval
- The FDA on Wednesday approved Canada-based Cangene Corporation's Anthrasil (Anthrax Immune Globulin), intended to be used with appropriate antibiotics to counteract that toxins produced when Bacillus anthracis is inhaled.
- Inhalational anthrax occurs after exposure to infected animals or contaminated animal products, or after the intentional release of anthrax spores.
- The Department of Health and Human Services’ (DHHS) Biomedical Advanced Research and Development Authority (BARDA) purchased Anthrasil with the intention of making it part of the U.S. Strategic National Stockpile. Without FDA approval, use of Anthrasil would not be allowable without emergency use authorization from the FDA.
Because it is unethical to test the efficacy of a product like Anthracil in humans, this drug was tested in animals to establish efficacy. The animals were first exposed to a lethal aerosolized dose of B. anthracis spores and subsequently treated with Anthracil. Among anthrax-infected monkeys treated with Anthrasil, survival rates ranged from 36% to 70%, compared with 0% in placebo-treated monkeys, according to the FDA.
With respect to Anthrax-infected rabbits, survival rates were 26%, compared with 2% in placebo-treated rabbits. However, once antibiotics were added to the rabbits’ treatment regimen, survival rates increased to 71%, compared with 25% for rabbits treated with antibiotics alone.
Although the efficacy studies were conducted on animals, a safety study was conducted in 74 healthy volunteers. Overall, the most common side effects were headache, back pain, nausea and infusion site pain and swelling. Anthrasil is manufactured by Canada-based Cangene Corporation using plasma from people vaccinated against anthrax, was tested in monkeys and rabbits.