Jan 27, 2003 (CIDRAP News) – Top federal health officials have turned down a proposal to test the Dryvax smallpox vaccine in small children, but not because of public objections. The trial is no longer needed because the current campaign to vaccinate military personnel and healthcare workers means Dryax won't be available for use in children, officials said.
Dryvax has been the foundation of the federal stockpile of smallpox vaccine. The government has about 15 million doses, but the current vaccination effort is expected to use millions of doses in the next several months. The government also has around 80 million doses of an old smallpox vaccine made by Aventis, and it has 209 million doses of a new vaccine on order from Acambis and Baxter International.
The decision not to approve the trial was made by Health and Human Services (HHS) Secretary Tommy Thompson and Food and Drug Administration (FDA) Commissioner Mark B. McClellan, according to Pat El-Hinnawy, a spokesman for the HHS Office for Human Research Protections (OHRP).
El-Hinnawy said the proposed trial became "moot" because the smallpox vaccination campaign as currently planned is likely to use up the supply of Dryvax, so the vaccine would not be used in children.
The proposed trial, sponsored by the National Institutes of Health, would have tested Dryvax in standard and diluted concentrations in children aged 2 to 5 years. Last October federal officials invited the public to comment on the proposal, and the idea drew hundreds of mostly negative comments. Critics said the risks to the children outweighed any possible benefits of the experiment.
The decision to call off the trial was stated in a letter from FDA and HHS officials to Harbor-UCLA Medical Center, one of two institutions that would have conducted the trial. The letter states that "bioterrorism preparedness plans have evolved such that, under current plans, the potential to use diluted Dryvax in children will no longer exist. In the absence of plans to use diluted Dryvax in children, the Secretary, HHS, and the Commissioner, FDA, have determined that there is no justification for this particular clinical investigation to proceed."
The decision applies only to this trial and does not rule out future research on smallpox vaccines in children, the letter states. It was signed by Irene Stith-Coleman, PhD, a divisional director in the OHRP, and David A. Lepay, MD, PhD, senior advisor for clinical science in the FDA.
A plan announced by President Bush in December calls for vaccinating about 500,000 public health and healthcare workers on volunteer smallpox response teams. The first of those vaccinations began last week. The plan also envisions vaccinating up to 10 million additional healthcare and emergency response workers in coming months. Immunization of military members began in December; HHS officials said last fall that they would provide 1 million doses of vaccine to the military. The plans announced in December also called for making smallpox shots widely available to the public in 2004.