FDA official proposes ‘impossible’ standards for vaccine testing that could curtail access to immunizations
The top vaccine regulator at the Food and Drug
Administration (FDA) wants to impose vague but sweeping new standards on
vaccine testing that, health experts say, would impede the development of new
immunizations and likely curtail access to life-saving shots, according to a
memo sent to staff on October 28.
Before vaccines, 50% of children did not reach adulthood.
With vaccines, that dropped to 4%
Vinay Prasad, MD, director of the FDA’s Center for Biologics
Evaluation and Research (CBER), proposed the "path forward" in an
internal memo in which he claimed—but provided no evidence—that COVID-19
vaccines caused the death of 10 children.
Many infectious disease experts say Prasad should share the
evidence on which he based his argument. Linking a vaccine to an adverse event
requires a high level of evidence, including autopsy results and medical
records that rule out other causes of death and show whether the affected
person was infected with the coronavirus itself, said Paul Offit, MD, an
infectious disease specialist at Children’s Hospital of Philadelphia and
co-inventor of a rotavirus vaccine.
Prasad is "making a fairly fantastic statement,"
Offit said. "He should provide extraordinary evidence that that's clear,
and he didn't, which is incredibly irresponsible and unprofessional to
do."
In the memo, Prasad wrote that the FDA's current vaccine approval process falls short.
In the future, the FDA will "demand pre-market
randomized trials assessing clinical endpoints for most new products,"
including vaccines, Prasad wrote. He noted that COVID-19 vaccines have not been
tested in randomized controlled trials (RCTs) in pregnant women. Such trials
are the most rigorous type of study, but they can cost millions of dollars and
take years to produce results.
"We will not be granting marketing authorization to
vaccines in pregnant women" without such evidence, Prasad wrote. The
memo's contents were first reported by a PBS News correspondent in
a series of posts on X, the social media platform.
Asking for the impossible
Demanding an RCT would prevent pregnant women from receiving
most vaccines, said Jake Scott, MD, a clinical associate professor of
infectious disease and geographic medicine at Stanford University School of
Medicine.
That's because pregnant women are almost never included in
RCTs of vaccines or other drugs due to potential risks to the fetus, Scott
said. Instead, the FDA does careful safety monitoring and measures antibody
levels in women's blood, which can show whether the vaccine is generating an
immune response.
In his memo, Prasad also wrote that "pneumonia vaccine
makers will have to show their products reduce pneumonia," at least after
they're licensed, rather than provide indirect evidence of protection, such as
antibody levels.
Prasad appears to refer to a childhood pneumonia vaccine
that blocks infections with pneumococcus bacteria, which has been updated and
improved several times over the years, said Dorit Reiss, PhD, a law professor
at the University of California Law, San Francisco. Although the first version
of the vaccine protected children from seven bacterial strains, the latest
iteration protects against 20 strains.
Pneumococcal vaccines on the market today are approved based
on antibody levels that correlate with protection and have been validated over
decades, Scott said.
Proving that childhood vaccines prevent cases of pneumonia
would be difficult, Scott said, because so many pathogens can cause pneumonia,
including the flu, COVID-19 and respiratory syncytial virus (RSV).
It would be unethical to use placebos and let people get
pneumococcal pneumonia.
Requiring manufacturers to conduct additional clinical
trials every time they want to add additional viral or bacterial strains would
delay updates by several years, all the while leaving people vulnerable to the
bacteria, Reiss said. Some companies may decide that conducting such trials is
too expensive.
"You'd need massive, expensive trials that many
companies won't pursue," Scott said.
Conducting RCTs of proven vaccines could also be unethical,
said Jesse Goodman, MD, who previously filled Prasad's role at the FDA and now
directs Georgetown University's Center on Medical Product Access, Safety and
Stewardship.
"It would be unethical to use placebos and let people
get pneumococcal pneumonia," Goodman said.
Flu vaccines also in crosshairs
Prasad's memo was also extremely critical of flu vaccine
testing.
But performing large clinical trials on each year's
influenza vaccines before the start of flu season would be impossible, Scott
said. Although vaccines are made the same way every year, the viral strains
used to produce them typically change each year, based on the viruses in
circulating. Scientists make their best guess about which strains to include in
Northern Hemisphere vaccines in February or March, because manufacturing them
takes six months.
Requiring any additional testing could prevent the vaccines
from being ready for the flu season, which begins in the fall in the Northern
Hemisphere.
Reiss said Prasad is correct when he says that flu shots get
minimal testing.
"But it's minimal testing for a reason," she said.
"If you're demanding more, you're making it almost impossible to approve
an annual vaccine. He didn't tell us exactly in detail what the FDA is going to
say, but is this is going to demand a large clinical trial every year. That's
just not going to happen."
Conducting an RCT of each season's flu vaccine would be
impossible, Scott said, given that these studies typically take several years.
If the FDA requires RCTs for annual flu shots, the results
would not be ready until years later, rendering the vaccines worthless, Scott
said.
Prasad issued his memo just days before a two-day meeting of
the Center for Disease Control and Prevention's (CDC's) influential vaccine
committee, which is scheduled to be held Thursday and Friday. The Advisory
Committee on Immunization Practices recommends which vaccines Americans should
receive, and its decisions influence which vaccines are covered by insurance or
federal programs.
Many researchers told CIDRAP News they fear that the
committee could use Prasad's memo to justify further restrictions on vaccines.
"Even if vaccines remain technically available,"
Scott said, "without CDC recommendations or insurance coverage, access
disappears. It's a de facto ban disguised as higher standards."
"The [influenza] virus has proven far more dangerous to
children than any documented vaccine risk," Scott said.
Ignoring benefits of COVID-19 vaccines
Prasad's memo focuses only on the potential risks of
vaccines, without considering their benefits or citing how many lives they have
saved, said Angela Rasmussen, PhD, a virologist at the Vaccine and Infectious
Disease Organization at the University of Saskatchewan.
In his memo, Prasad harshly criticized the FDA for
authorizing COVID-19 vaccines for children, as well as the CDC, which
encouraged kids to receive the shots.
"Healthy young children who faced tremendously low risk
of death were coerced, at the behest of the Biden administration, via school
and work mandates, to receive a vaccine," Prasad wrote.
It's a de facto ban disguised as higher standards.
Research shows that COVID-19 caused 1,642 deaths in
children from 2020 to June 2023. Even by conservative estimates,
vaccines saved the lives of 299 children
from 2020 to 2024.
Demetre Daskalakis, MD, who led the CDC's National Center
for Immunization and Respiratory Diseases in August, defended the agency's
actions during the pandemic, noting that policy makers often must make public
health decisions based on incomplete or imperfect information.
"The quest for perfect data to make decisions is not
feasible," said Daskalakis, who resigned from the CDC in August after
Health and Human Services Secretary Robert F. Kennedy Jr. fired
the agency's director after less than a month in the position.
"We have to make decisions in public health with the
best data available to make recommendations and guidelines that are
implementable and realistic and based in the best science," Daskalaki
said. "Creating impossible standards demonstrates a lack of understanding
of public health and the role of agencies in balancing risk and benefit."
Reiss, the legal scholar, said Prasad's memo is
"legally tricky."
The FDA typically follows an established procedure when
making regulations. The agency usually issues a proposed regulation and
solicits outside comments from experts and the public before issuing a final
rule.
Vaccine manufacturers could sue the FDA, charging that the
changes violate federal laws by being "arbitrary and capricious,"
Reiss said. Legally, Prasad "needs to have some really good reasons"
to make such sweeping changes if he wants them to survive judicial review.
"If they decide to sue, they would have some very good arguments about
this being arbitrary and capricious" and undermining the ability of
companies to rely on the FDA's word.
The president of the American Academy of Pediatrics said she
agrees that vaccines should be rigorously tested.
"Parents deserve transparent communication to make
informed decisions," said Susan Kressly, MD, the academy's president, in a
statement.
"We are concerned that the newly proposed requirements
could limit children’s access to safe, proven vaccines," Kressley said.
"The existing approval process already includes robust testing that
carefully weighs benefits and risks to protect children. Preserving a strong,
science-based framework is critical to ensuring families can continue to access
the vaccines they need."
