(CNN) — The US Food and Drug Administration is expected to announce within the next 48 hours that it is authorizing Covid-19 vaccine booster shots for some people who are immunocompromised, according to a source familiar with the discussions.
This would be a third shot of the current two-dose Pfizer and Moderna vaccines. That announcement could slide, the source cautioned, but this is the current timing.
“The FDA is closely monitoring data as it becomes available from studies administering an additional dose of the authorized COVID-19 vaccines to immunocompromised individuals,” an FDA spokesperson told CNN. “The agency, along with the CDC, is evaluating potential options on this issue, and will share information in the near future.”
NBC News was first to report on the expected announcement.
The FDA must give authorization for the vaccines to be used in new ways outside the existing authorization. All three Covid-19 vaccines being used in the US are given under emergency use authorization by the FDA, but full approval is pending for Pfizer’s vaccine. After FDA grants approval or authorization, the US Centers for Disease Control and Prevention then advises on whether to actually use a vaccine as authorized by the FDA.
Vaccine advisers for the CDC will meet on Friday to discuss booster doses of Covid-19 vaccines and additional doses for some immunocompromised people, according to a meeting agenda posted by the agency on Monday.
A recent study by Johns Hopkins researchers found that vaccinated immunocompromised people are 485 times more likely to end up in the hospital or die from Covid-19 compared to the general population that is vaccinated.
Based on an estimate by the CDC, about 9 million Americans are immunocompromised, either because of diseases they have or medications they take.
It has been known for months that Covid-19 vaccines might not work well for this group. The hope was that vaccination rates overall would be so high so that the “herd” would protect them.
But it didn’t work out that way, because about a third of eligible people in the US have not received even one dose of a Covid-19 vaccine.
This is a breaking story and will be updated.
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