A top Food and Drug Administration (FDA) official said Friday that the agency will try to have a “streamlined” process for authorizing any updates that are required for COVID-19 vaccines to adapt to the threat of new variants.
“We would intend to try to be pretty nimble with this,” said Peter Marks, the head of the FDA center that reviews vaccines, during a webinar hosted by the American Medical Association.
Marks said the agency would work to “get these variants covered as quickly as possible.”
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.
Moderna, for example, said that while its studies have shown a reduced antibody response to the South African variant, its vaccine still appears to be protective, but “out of an abundance of caution” it is testing an updated vaccine specifically targeted against the new variant.
Relatively speedy authorization from the FDA would therefore also be important if vaccines need to be updated to adapt to new variants.
Marks said Friday the agency is “working on kind of finalizing what that will look like.”
He said for sure, though, that the updated vaccine would not have to go through another full-scale phase three trial to test its efficacy.
Instead, he said the agency could require “some small clinical trials” to ensure that the updated vaccine is triggering an immune response, and to see if it protects against both the new variant and the original virus.
The type of vaccines used by Moderna and Pfizer, known as mRNA vaccines, are relatively easy to update for new variants.
However, 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.
Some experts have called for giving people only one dose of the two-dose regimen as a starting point so that the limited supply can be stretched to more people.
Marks again pushed back on that idea on Friday, saying when there is 95 percent efficacy with two doses, “you don’t want to try to mess with success.”
With just one dose “we don’t know the duration of that protection,” he said.