Bioethicists proposed limits today on the types of clinical trials of anthrax vaccine and other drugs and vaccines aimed at bioterror agents that can be conducted in children.
The recommendation came in a report from the US President’s Commission for the Study of Bioethical Issues. US Secretary of Health and Human Services Kathleen Sebelius requested that the commission study the ethical dimensions of a possible anthrax vaccine trial in children after a federal biodefence science advisory board voted in favour of such trials.
A US Navy corpsman prepares an anthrax vaccination shot aboard the aircraft carrier USS George H.W. Bush. Courtesy MILVAX, the US Military Vaccine Agency.
“The safety of our children is paramount, and we have to get this right,” said Amy Gutmann, chair of the commission. “The commission concluded many steps would have to be taken…before pediatric anthrax vaccine trials prior to an attack should be considered by the U.S. government.”
Interest in a vaccination campaign was spurred by a 2011 modelling exercise, ‘Dark Zephyr’, which found that a release of anthrax spores in a city the size of San Francisco, California, would compel officials to vaccinate 7.6 million people — including 1.7 million individuals under age 18.
But clinical trials are not normally conducted in children unless there is a chance that children can benefit from the trials. And the risk of a bioterror attack is uncertain, making such trials ethically complicated.
The President’s commission said that until a bioterror attack occurs, tests of anthrax vaccine or other anti-bioterrorism “countermeasures” should not pose risks greater than those that a child might encounter in daily life or during a routine pediatric checkup.
To prove that anthrax vaccine trials would pose such a small risk, more tests of the vaccine should be done in animals and in young adults, the commission said. Then, testing of the vaccine should be done in progressively younger and more vulnerable age groups, the commission said.
Officials should also plan for tests of the vaccine that could be done in the event of an actual bioterror attack, the commission said.
John Parker, chair of the National Biodefense Science Board, which made the initial recommendation to study the anthrax vaccine in children ahead of an attack, said that the defence department probably already has data on how the vaccine affects 16- and 17-year-olds — who are, technically, children — who have received the vaccine through military service. Studies on these and younger children would need to clarify whether their immunological response to the vaccine is similar to that seen in adults, and whether children should receive a different dose of vaccine than is given to adults, Parker said.
“To get that kind of knowledge, you don’t need huge studies, but they would take time,” he said.
Such studies might help parents in the event that a bioterror attack with anthrax does occur, and they are asked to allow their children to receive a dose of the anthrax vaccine, as called for by current emergency plans.
“In the chaos of an anthrax exposure, I just think a little knowledge up front my contribute to a decreased amount of parental concern and being put on the spot to consent to have a vaccine where there’s no data,” said Parker, who was speaking on behalf of himself and not for the biodefence science board, which has not met to consider the bioethics commission’s report.
The health and human services department, which must now decide whether to accept the commission’s recommendations, issued a statement thanking the commission for its work.
“We look forward to fully reviewing the report,” the statement said.
