Test Of Anthrax Vaccine In Children Approved
A presidential ethics panel has opened the door to testing an anthrax vaccine on children as young as infants, bringing an angry response from critics who say the children would be guinea pigs in a study that would never help them and might harm them.
The report, however, released on Tuesday by the Presidential Commission for the Study of Bioethical Issues, said researchers would have to overcome numerous hurdles before launching an anthrax-vaccine trial in children. It now goes to Secretary of Health and Human Services Kathleen Sebelius, who will decide whether to take the steps the commission recommended.
The one anthrax vaccine approved in the United States, called BioThrax, is made by Emergent BioSolutions Inc of Rockville, Maryland. The company reported $215.9 million in sales of BioThrax, its only licensed product, in 2012.
The ethics commission took up the issue after a biodefense panel recommended in 2011 that the anthrax vaccine be tested in children. That endorsement, by the National Biodefense Science Board, came with the caveat that such a study also get the go-ahead from a bioethics panel.
It did, albeit conditionally.
“We have to get this precisely right,” panel Chair Amy Gutmann, president of the University of Pennsylvania, said at a news conference. “Many significant steps would have to be taken” before a pediatric anthrax vaccine trial could be considered, she said. But she added that it is important “to develop the knowledge needed to save children’s lives” in the event of an anthrax attack.
Balancing the need to protect children against the need to know, for instance, the safe dose of the vaccine, made this “one of the most difficult ethical reviews a bioethics board has ever conducted,” Gutmann said.
Activists said the board was wrong not to oppose unequivocally testing the anthrax vaccine in children.
Vera Sharav, founder of the Alliance for Human Research Protection, predicted that such a study would cause “moral harm for us as a nation and suffering for the children. They should have said, ‘thou shalt not.’”
The idea of testing an anthrax vaccine in children arose when a 2011 war game, called Dark Zephyr, presented to policy makers a scenario in which terrorists released anthrax on a city modeled on San Francisco. Doctors did not know what dose of the vaccine to give children. That presented a dilemma: should children be vaccinated anyway, or should the government test the vaccine on them first to establish a safe dose?
Information about safety has come from giving the vaccine to some 2.9 million adults, mostly members of the armed forces who were thought to be at risk of exposure to biological weapons in Iraq. Information about efficacy has come from animal studies, as it is unethical to expose someone to anthrax intentionally to see if the vaccine works, and from measurements of the anthrax-fighting antibodies a vaccinated person produces.
Federal regulations set a high bar for research on kids. If the chance of their benefiting is minuscule or nil, and the potential risk even minimal, children are usually off-limits.
The presidential bioethics panel conceded that “there is no prospect of direct benefit to children” who participate in an anthrax-vaccine study, Gutmann said. According to the biodefense board, children in such a study would face more than minimal risk (defined as a risk no greater than that in daily life or at a check-up), mostly because the side effects of the vaccine in children are unknown.
Because the vaccine poses more than minimal risk to children, any proposal for testing it in them would have to clear several hurdles, the commission said. One pre-requisite for such a study is rigorously testing the vaccine in the youngest adults, starting at age 18.
“You’d work your way down from 18-year-olds,” said Dr. John Parker, a retired army major general and chairman of the biodefense board. “If it were safe you’d go to 17-year-olds, then 16-year olds.” After each round showing minimal harm, “you’d ask permission to move on to younger children.”
The youngest age for testing is not clear, said Parker, “but the immune system of very young children is different from older people’s.” Results in 16-year-olds or even 5-year-olds might not reveal whether the vaccine is safe in babies, who would therefore have to be studied, too.
To critics, the combination of no benefit and some risk to children means a pediatric anthrax-vaccine study should be prohibited.
“We have to wonder if, after all the data collected by the U.S. Army on the side-effects experienced by soldiers, we would want to subject children to skin ulcers symptoms of the disease,” said Jeanne Guillemin, a senior fellow in the Massachusetts Institute of Technology’s Security Studies Program and author of a 2011 book about anthrax attacks, titled “American Anthrax.”
In the largest study of the anthrax vaccine, the U.S. Centers for Disease Control and Prevention reported in 2008 that in 1,563 adults who received the vaccine, there were 229 “serious adverse events” such as cardiovascular disease, intracranial aneurysm and seizure, though only nine were blamed on the vaccine. Much more common were milder reactions such as soreness near the injection site, itching, fever and malaise.
Opponents of testing the anthrax vaccine in children argue that antibiotics would be sufficient to protect kids in an anthrax attack.
Antibiotics worked following attacks in 2001 that were traced to an Army scientist who committed suicide in 2008 as investigators closed in. The five people who died after inhaling anthrax spores sent through the mail did not receive antibiotics before developing symptoms. Everyone who was exposed and received antibiotics in time survived, noted MIT’s Guillemin.
Proponents of testing the anthrax vaccine in children argue that antibiotics are not enough.
“The point of vaccinating is that anthrax spores can hatch at different times and stay dormant for days to months,” said Dr. Daniel Fagbuyi of Children’s National Medical Center in Washington, D.C., and a member of the biodefense board.
Vaccination, he said, would prevent disease long after victims’ 60-day course of antibiotics is finished.
Under a 2005 law, children in an anthrax-vaccine study would be prohibited from seeking damages through the legal system. The presidential commission, said Gutmann, “strongly recommended that a plan be in place to compensate any children” who are harmed.