FDA recommends shorter trials for updated coronavirus vaccines

FDA recommends shorter trials for updated coronavirus vaccines
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Vaccine developers will not have to conduct lengthy clinical trials to evaluate the effectiveness of shots tailored to fight new coronavirus variants, according to new guidance from the Food and Drug Administration (FDA).

According to the guidance released Monday, developers will not need large randomized control trials comparing it to a placebo.

Instead, the FDA said it recommended companies submit data from small trials comparing a person's immune response to a vaccine that has already been authorized. 


The new guidance recommendations would speed up the review process for booster shots or new vaccines, a welcome development as experts worry about how coronavirus mutations could impact vaccines.

“We know the country is eager to return to a new normal and the emergence of the virus variants raises new concerns about the performance of these products. By issuing these guidances, we want the American public to know that we are using every tool in our toolbox to fight this pandemic, including pivoting as the virus adapts," Janet Woodcock, the agency's acting commissioner, said in a statement.

Experts have not yet said that updated vaccines are necessary, but they are monitoring the situation closely, particularly a variant first identified in South Africa that has been shown to diminish the effect of vaccines to varying extents.

Woodcock told reporters on Monday the guidance was not meant as an indication that new vaccines would be needed, but is about being prepared.

"I think we need to anticipate this and work on it, so that we have something in our back pocket before the threshold is upon us, so to speak," Woodcock said.

Peter Marks, the head of the FDA center that reviews vaccines, told reporters he expects the trials to be composed of only a "few hundred individuals," which would only take two or three months, rather than tens of thousands of people.


Marks said the agency doesn't yet know what data might trigger developers to start making new vaccines, but the decision would likely involve a global process, including input from the World Health Organization and other regulatory agencies.

"We need to have the studies conducted to facilitate potential strain changes, sooner rather than later. So that if we need to swap something in, we can do it in a relatively quick manner, because as we've learned that these variants can sometimes move through the population very quickly so we want to be prepared for them," Marks said.

The type of vaccines used by Moderna and Pfizer, known as mRNA vaccines, are relatively easy to update for new variants. The companies said the process could take about six weeks, but that doesn't include regulatory review.

Experts say it is best to vaccinate as many people as quickly as possible with the current vaccines to cut down on the opportunities for the virus to continue spreading and mutating.

Basic precautions like mask wearing, avoiding indoor gatherings and maintaining six feet of distance from others are also crucial in slowing the spread and reducing further mutation.