Wednesday, September 23, 2020

Past fiascos show need for vaccine caution


September 1, 2020 - "Vaccine experts are warning the American government against rushing out a coronavirus vaccine.... Their concern that the Food and Drug Administration 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 An EUA is not the same as full approval and it can be withdrawn....

"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.
  • 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.
  • 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).... Scientists wrongly thought the formaldehyde they used would kill the virus.... No current vaccines contain SV40 virus, the CDC [U.S. Center for Disease Control] says, and there's no evidence the contamination harmed anyone.
  • In 1976, scientists predicted a pandemic of a new strain of influenza called swine flu. '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.... 'Ford was being cajoled to put forward a vaccine that was hastily put together'.... Ford made the decision to make the immunization compulsory ...  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....
  • The CDC said the increased risk was about one 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....
"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'.... '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.... A too-early EUA for a vaccine could cause a 'nightmare scenario,' for a few reasons.

"One, the vaccine may not be safe. Two, if it is not safe, people will lose faith in vaccines. Three, if a vaccine doesn't offer complete protection, people will have a false sense of security and increase their risk. Four, if a substandard vaccine gets an EUA, a better vaccine may never get approval, because people would be reluctant to enroll in trials and risk getting a placebo instead of a vaccine."


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