Bioethics Panel Gives Yellow Light to Anthrax Vaccine Trial in Children

Cautious. A new report examines the ethics of testing an anthrax vaccine in children.

President Barack Obama's bioethics commission says that the U.S. government could consider testing the anthrax vaccine in children, if certain conditions are met.

Whether and how to test biodefense treatments in children is controversial because such studies would expose kids to the risks of, say, a new vaccine, when they are unlikely to directly benefit from the research. Yet without such testing, medical personnel would not know what dose to give children if a bioterrorism attack occurred. In fall 2011, the National Biodefense Science Board (NBSB), which advises the Department of Health and Human Services (HHS), urged the government to launch an anthrax vaccine trial in children pending ethics approval. HHS Secretary Kathleen Sebelius then asked the Presidential Commission for the Study of Bioethical Issues to take a look at that possible trial and the broader issues. (The panel did not review a specific protocol.)

"This was one of the most difficult ethical reviews that any bioethics commission has ever conducted," said the commission's chair, Amy Gutmann, president of the University of Pennsylvania. In a 146-page report released today, the commission concludes that an anthrax vaccine trial with children should take place only if the risks are "minimal"—comparable to a blood draw or soreness around the injection site. So, to consider such a trial, researchers would first need to demonstrate with data from young adults (18 to 20 years old) that the risks are likely minimal for older teenagers. For instance, researchers could look at safety data from the young adults who are among the more than 1 million U.S. military personnel who have received the 4-decade-old anthrax vaccine, Gutmann said.

The vaccine could be tested in older children (say 16- to 17-year-olds) and then, if safe, in progressively younger age groups. The same principles should apply to other tests of medical countermeasures in children, the report says.

"Many steps would have to be taken" for an anthrax vaccine trial in children to be approved, Gutmann said. She added, however, that "it is not our intent to determine whether or not the government goes ahead."

A biodefense trial with children that posed greater than minimal but still minor risk—comparable to a low fever or chest x-ray—might also be possible under "extraordinary circumstances," but would require approval by a national ethics panel, as is required by existing rules, the commission concluded. To guide such an ethics review, the report lays out an ethical "framework." For example, it asks if the study addresses a "serious problem," defined by the threat of exposure and the possible consequences. The report also says the United States should have research plans in place if it intends to launch a study in children following a bioterror attack.

The age de-escalation approach is often used in testing pediatric vaccines but "had not been discussed" for the anthrax vaccine, said commission member Christine Grady, bioethics chief at the National Institutes of Health's Clinical Center in Bethesda, Maryland. She and Gutmann said that the anthrax vaccine is considered to pose minimal risk in adults; it is made from an inactivated protein from the anthrax bacterium, which makes it similar to some childhood vaccines. But NBSB assumed there was more than a minor risk in children because it considered ages 0 to 17 as a group and did not have data to show otherwise, Gutmann said.

The panel's advice that the anthrax vaccine be tested in progressively younger age groups "isn't surprising," says infectious disease researcher Paul Offit of the Children's Hospital of Philadelphia in Pennsylvania, who is a proponent of childhood vaccinations but opposes a pediatric anthrax vaccine trial. He says the report doesn't change his views because the children would "have essentially no chance of benefiting." He says the one exception might be if military families wanted their children in a trial because they thought they could be at risk for anthrax exposure. "That would be reasonable," Offit says.

The bioethics commission's report notes that military families have been mentioned as a possible group in which to test the vaccine, but cautioned that these families should not feel pressured into volunteering their children for such a study.