This article is more than 5 years old. Information may no longer be current.
FDA approves anthrax vaccine for suspected, confirmed exposure
Click Here to Manage Email Alerts
The FDA recently approved a new indication for the anthrax vaccine BioThrax to prevent disease in individuals who may have been exposed to Bacillus anthracis, according to a press release.
BioThrax (Anthrax Vaccine Adsorbed, Emergent BioSolutions) originally was approved in 1970 to prevent disease in individuals at high risk for exposure, but not for those with suspected or confirmed exposure to anthrax. The new approval applies to adults aged 18 to 65 years receiving recommended antibiotic treatment.
Karen Midthun
“With [the] approval of BioThrax, we now have a vaccine that can be used, together with antibiotic treatment, to prevent disease after exposure to anthrax spores,” Karen Midthun, MD, director of the FDA’s Center for Biologics Evaluation and Research, said in the release.
Patients can develop anthrax disease after exposure to infected animals or contaminated animal products. When treatment is delayed, the disease, particularly the inhalation form, often results in death. The FDA advised that anthrax is among a class of agents that would likely be used in a biological attack because its spores are stable and easy to disperse.
BioThrax is the first vaccine approved by the FDA based on the Animal Rule. The rule allows the use of data from animal efficacy trials when human efficacy trials are not ethical or feasible. Rabbits treated with BioThrax and antibiotics had a 70% to 100% survival rate, depending on the vaccine dose, compared with a 44% to 23% survival rate with antibiotic treatment alone.
The safety and protective antibody responses to BioThrax were evaluated in humans during a multicenter study. Researchers administered three biweekly, subcutaneous injections to 200 healthy adults and estimated the majority of participants generated antibody responses that yielded a 70% survival probability. The majority of adverse events were tenderness, pain, swelling, injection site redness and limited movement of the injected arm, which were similar to events observed in pre-exposure disease prevention cases. The most common systemic adverse reactions included muscle ache, headache and fatigue.