The U.S. Court of Appeals in Washington upheld a lower court's decision dismissing a case brought by eight service members who challenged the Food and Drug Administration's determination that the vaccine was effective.
The plaintiffs also wanted to stop the Defense Department's requirement that service members at risk for anthrax exposure must be vaccinated.
Anthrax is a bacterial disease caused by infection with spores that mainly affects animals but that humans can contract through skin contact, inhalation and ingestion. Inhaled anthrax is more difficult to treat and can be fatal.
The military's vaccine, produced by Michigan-based Bioport Corp., was approved based on a human test in the 1950s that studied textile workers at risk for the disease because they routinely handled infected imported goat hair. Since then industrial conditions have improved and there has not been another study because of the health risks associated with exposing people to the spores.
The service members argued that because the one human study included only a few inhalation cases, there is insufficient evidence to conclude the vaccine is effective against them.
But the appeals court ruled that the service members who filed the suit did not provide any scientific evidence to prove the vaccine was ineffective. "We are presented with a scientific judgment by the FDA to which we owe considerable deference," the court found.
John J. Michels Jr., attorney for the service members, said the case shows how difficult it is to challenge a ruling by a federal agency. He said they had not decided whether to appeal the case further.