The U.S. health department, under the guidance of Health Secretary Robert F. Kennedy Jr., says it intends to add the requirement of a placebo testing phase in vaccine trials to provide more transparency about medical products, but experts warn the process could threaten immunization access and create public mistrust in the efficacy and validity of inoculations.
In a statement to the Washington Post this week, a spokesperson for the Department of Health and Human Services (HHS) said, “All new vaccines will undergo safety testing in placebo-controlled trials prior to licensure — a radical departure from past practices.”
If implemented, the new regulations would require some test subjects to receive vaccine doses, while others would be injected with a non-reactive substance.
Vaccines that target new infectious agents are often tested using the placebo method, but for well-known and researched diseases, health experts say using a placebo poses ethical issues because the group receiving it will not know if they are actually protected against the illness.
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The health department did not provide details on how the proposed changes will be enforced or to which vaccine trials they will apply. It also did not define what it meant by “new vaccine,” though it said the policy would not include the flu shot, which is updated yearly.
Health experts have argued that updated COVID-19 vaccines may be included, which they say could delay access.
Peter Lurie, a former Food and Drug Administration (FDA) official, told the BBC, “It’s hard to tell exactly what is being proposed.”
“But, broadly, if they mean that every modification to an existing vaccine would require a new placebo-controlled trial, they are treading in ethically dubious territory and likely to deny Americans life-saving vaccines at some point.”
An HHS spokesperson also told the BBC that Kennedy’s goal is to achieve “radical transparency,” which means “being honest and straightforward about what we know—and what we don’t know—about medical products, including vaccines.”
The statement went on to claim that none of the vaccines recommended for children in the U.S., except the COVID-19 shot, had gone through placebo testing, which the health department says leaves it knowing “very little about the actual risk profiles of these products.”
However, health experts warn that the statement is misleading because vaccines administered to children, including for hepatitis A and B, polio, and mumps, were all tested against a placebo during their development stages.
The BBC adds that all new immunizations go through a type of random testing where one test group receives the vaccine and the other is given a placebo.
But in the new system proposed by HHS, experts say vaccines under testing may not undergo the same randomized process, because it is unethical to withhold an injection that is known to be safe from a particular group, and because shots that are updated yearly go through minimal alterations.
For example, the COVID-19 vaccine has endured scrupulous testing for years, and all of that is necessary to update it for a different Omicron variant than the one used the year prior, Paul Offit, director of the Vaccine Education Center at Children’s Hospital of Philadelphia, told the BBC.
Nevertheless, an HHS spokesperson said that “significant updates to existing vaccines” could be seen as “new products,” which could necessitate additional trials.
“A four-year-old trial is also not a blank cheque for new vaccines each year without clinical trial data, unlike the flu shot, which has been tried and tested for more than 80 years,” the spokesperson told the BBC.
Meanwhile, Lurie says requiring placebo tests for basic updates to existing vaccines that are proven to work would be expensive and could lead to drug companies opting not to upgrade them altogether.
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