RFK Jr. to require placebo-controlled studies for new vaccines

The Trump administration plans to impose a new testing requirement for new vaccines — a demand that could delay the availability of the next round of COVID-19 vaccines and complicate the approval of other vaccines.

The administration will require all new vaccines to be tested against an inert substance known as a placebo before they can be made available, which is a "radical departure from past practices," according to a statement from Andrew Nixon, a spokesman for Robert F. Kennedy Jr., the secretary of Health and Human Services.

The latest statement triggered alarm among vaccine experts that this may be another step by Kennedy to undermine the confidence in and availability of vaccines.

"I think it is the interest of Robert F. Kennedy Jr. to make vaccines more expensive, less available and more feared," said Dr. Paul Offit, a University of Pennsylvania vaccine expert. "He's an anti-vaccine activist, a science denialist who is going to do everything he can to tear down the infrastructure in this country of vaccines. Robert F. Kennedy Jr is a dangerous man."

The administration maintains this new requirement is aimed at ensuring vaccines are safe. But vaccine experts dispute the claim that key vaccines weren't tested against a placebo. They also take issue with the definition of what constitutes a new vaccine. The ingredients in some vaccines, such as the COVID shots, have been updated regularly to better match the strains of the SARS-CoV-2 virus in circulation, without fundamentally changing the vaccines themselves. That has long been the case with flu vaccines, too.

"Secretary Kennedy's HHS has pledged radical transparency to the American public. This means being honest and straightforward about what we know — and what we don't know — about medical products, including vaccines," Nixon said.

He also claimed that "except for the COVID vaccine, none of the vaccines on the CDC's childhood recommended schedule was tested against an inert placebo, meaning we know very little about the actual risk profiles of these products."

Nixon also questioned the reliability of existing vaccine monitoring programs, which he described as "regulatory malpractice."

Change in standard could delay future COVID shots

While the administration didn't specifically name the COVID vaccines, Nixon indicated any update to the COVID vaccines could make them new vaccines that would require this testing.

"As we've said before, trials from four years ago conducted in people without natural immunity no longer suffice. A four-year-old trial is also not a blank check for new vaccines each year without clinical trial data, unlike the flu shot which has been tried and tested for more than 80 years," Nixon said in a statement he had earlier sent to The Washington Post. "The public deserves transparency and gold-standard science — especially with evolving products."

He also referred to recent comments from Food and Drug Administration Commissioner Marty Makary indicating the COVID vaccines should be considered new vaccines.

"Makary has indicated that significant updates to existing vaccines—such as those addressing seasonal strain changes or antigenic drift—may be considered 'new products' requiring additional clinical evaluation," Nixon wrote. "He emphasized the need for robust data to support vaccine approvals, highlighting, 'Rather than allow that void to be filled with opinions, I'd like to see some good data.' "

The moves are concerning at a time when vaccination rates are already falling and diseases like measles are experiencing outbreaks. COVID is still killing hundreds of Americans every week, and the next pandemic could hit at any time, Offit and others say.

"He appears to be on full-on attack mode when it comes to vaccines. And it's so self-defeating for our country and globally as well," says Dr. Peter Hotez, a vaccine researcher at the Baylor College of Medicine in Houston. "It's absolutely dangerous."

Placebo-controlled vaccine trials have been common

Offit, Hotez and others disputed the claim that testing vaccines against a placebo is a "radical departure" and that childhood vaccines were not evaluated that way. Scientists routinely test new vaccines and drugs against placebos to see if they are safe and effective.

"The blanket statement that none of the routine vaccines were ever tested against placebo is incorrect," says Dr. Jesse Goodman, a former Food and Drug Administration vaccine regulator now at Georgetown University. "Placebo trials have been done."

That includes the original COVID vaccines, which were evaluated in large, well-designed placebo-controlled trials that evaluated their safety and effectiveness. Those trials, along with subsequent monitoring, have clearly shown that the COVID vaccines as well as all the other shots on the market are safe and effective, Goodman and others say.

Given how much immunity people have at this point, any new placebo trials for the update COVID vaccines would have to be huge, which means it would be prohibitively expensive and would take too long to make the updated vaccines available in time for next fall and winter, they say.

"By the time you got those studies done, the strain would have evolved and the study you just did would be of a strain that's not as good," Goodman says. "You'd be deliberately creating a situation where you would probably be using less-good vaccines – and for no reason."

"It would basically be a recipe for paralysis," Hotez says.

In addition, experts say that giving someone a placebo to protect them against a potentially deadly disease when an effective vaccine already exists would be unethical.

"Are they really planning on doing a placebo-controlled trial where a certain group of people are not given that vaccine, knowing that the virus can cause infection and disease, including serious disease in anyone? Anyone can be felled by this virus," Offit says. "So it's not an ethical trial."
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