(CNN) “Vaccine experts are
warning the federal government against rushing out a coronavirus vaccine before
testing has shown it's both safe and effective. Decades of history show why
they're right.
FDA signals vaccine
could green light early
“Their concern that the
FDA may be moving too quickly heightened when FDA Commissioner Dr. Steven Hahn
told the Financial Times that his agency could consider an emergency use
authorization (EUA) for a Covid-19 vaccine before late stage clinical trials
are complete if the data show strong enough evidence it would protect people.
“The commissioner has the authority to allow unapproved
medical products to be used in an emergency when there are no adequate or
approved alternatives. An EUA is not the same as full approval and it can be
withdrawn.
“That's what happened with
hydroxychloroquine and chloroquine. The FDA granted an
EUA to the drugs -- much praised by President Donald Trump -- on March 28. It subsequently revoked its
EUA in June after studies showed they were not effective and could also potentially cause serious heart problems.
Vaccine approval
“For a vaccine to be FDA approved, scientists must gather enough data through
clinical trials in large numbers of volunteers to prove it is safe and
effective at protecting people against a disease. Once the data is collected,
FDA advisers usually spend months considering it.
“An EUA is much quicker. Only once before has the FDA given
a vaccine this lesser standard approval of an EUA, but it was in an unusual circumstance.
Soldiers had sued, claiming a mandatory anthrax vaccine made them sick, and a
judge put a hold on the program. The Department of Defense asked for an EUA that then overrode
the court ruling in 2005, so it could continue vaccinating military personnel
-- this time on a voluntary basis.
“Otherwise, vaccines have had to
go through the entire clinical trial process and FDA approval process, which
can take months or years. When the vaccine making process has been rushed,
there have been bad outcomes.
The Cutter incident
“On April 12, 1955 the
government announced the first vaccine to protect kids against polio. Within
days, labs had made thousands of lots of the vaccine. Batches made by one
company, Cutter Labs, accidentally contained live polio virus and it caused an
outbreak.
“More than 200,000 children got
the polio vaccine, but within days the government had to abandon the program. ‘Forty
thousand kids got polio. Some had low levels, a couple hundred were left with
paralysis, and about 10 died,’ said Dr. Howard Markel, a pediatrician,
distinguished professor, and director of the Center for the History of Medicine
at the University of Michigan. The government suspended the vaccination program
until it could determine what went wrong.
Monkey trouble
“However, increased oversight
failed to discover another problem with the polio vaccine. From 1955 to 1963,
between 10% and 30% of polio vaccines were contaminated with simian virus 40 (SV40). ‘The way they
would grow the virus was on monkey tissues. These rhesus macaques were imported
from India, tens of thousands of them,’ medical anthropologist S. Lochlann Jain
said. ‘They were gang caged, and in those conditions, the ones that didn't die
on the journey, many got sick, and the viruses spread quickly,’ added Jain, who
taught a history of vaccines course at Stanford and is working on a publication
about the incident. Scientists wrongly thought the formaldehyde they used would
kill the virus. ‘It was being transferred to millions of Americans,’ Jain said.
‘Many believe this issue wasn't adequately pursued,’ Jain said. Some studies
showed a possible link between the virus and cancer. The US Centers for Disease
Control website, however, said most studies are ‘reassuring’ and find no link.
“No current vaccines contain
SV40 virus, the CDC says, and there's no evidence the contamination harmed
anyone.
The epidemic that never
was
“In 1976, scientists predicted a
pandemic of a new strain of influenza called swine flu. More than 40 years
later, some historians call it ‘flu epidemic that never was.’ ‘President Ford
was basically told by his advisers, that look, we have a pandemic flu coming
called swine flu that may be as bad as Spanish flu,’ said Michael Kinch, a
professor of radiation oncology in the school of medicine at Washington
University in St. Louis. His latest book, ‘Between Hope and Fear,’ explores the
history of vaccines. ‘Ford was being cajoled to put forward a vaccine that was
hastily put together. When you have a brand new strain situation like that,
they had to do it on the fly,’ Kinch said.
“Ford made the decision to make
the immunization compulsory. The government launched the program in about seven
months and 40 million people got vaccinated against swine flu, according to the
CDC. That vaccination campaign was later linked to cases of a neurological
disorder called Guillain-Barre syndrome, which can develop after an infection
or, rarely, after vaccination with a live vaccine. ‘Unfortunately, due to that
vaccine, and the fact that it was done so hastily, there were a few hundred
cases of Guillain-Barre, although
it's not definitive that they were linked,’ Kinch said.
“The CDC said the increased risk was about 1 additional case
of Gullain-Barre for every 100,000 people who got the swine flu vaccine. Due to
this small association, the government stopped the program to investigate. ‘It
was kind of a fiasco,’ Markel said. ‘The good news is that there never was an
epidemic of swine flu. So, we were safe, but that shows you what could happen.’
Growing distrust in the
US
“It took several incidents for
people to start distrusting vaccines. Even after thousands of kids got sick
from the first polio vaccine in 1955, when the program restarted, parents made
sure their children were vaccinated. They had clear memories of epidemics that
paralyzed between 13,000 and 20,000 children every year. Some were so
profoundly paralyzed that they could not even breathe easily on their own, and
relied on machines called iron lungs to help them breathe. ‘Parents were
pushing their kids to get to the head of the line to get the polio vaccine,
because they had seen epidemics every summer for years, and saw kids in iron
lungs and they were terrified,’ Markel said.
“Markel said people's attitudes
started to change between 1955 and the problematic 1976 swine flu vaccination
project. ‘You've got civil rights, when people see the cops beating the hell out
of people on TV. You've got the Vietnam War where people start to get disgusted
with the killing. You've got Watergate when the president is literally lying
through his teeth,’ Markel said. ‘That led to a real distrust of authorities
and federal government, and it extended to doctors and scientists. And, that's
only progressed as time has gone along.’
“Markel said people's mistrust
of the system makes the idea that the FDA would rush this process before late
stage clinical trials are complete ‘colossally stupid.’ ‘This is
one of the most ridiculous things I've heard this administration say,’ Markel
said. ‘All it takes is one bad side effect to basically botch a vaccine program
that we desperately need against this virus. It's a prescription for disaster.’
“FDA Commissioner Hahn said that
the vaccine decision will be based on data, not politics, but Kinch shares
Markel's concern. ‘This
could do substantial damage,’ Kinch said. Kinch, who is a patient in one of the
vaccine trials himself, said the clinical trial process needs to be followed to
the end. A too-early EUA for a vaccine could cause a ‘nightmare scenario,’ for
a few reasons” (CNN).
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.