According to news reports, the U.S. Food and Drug Administration will authorize a third dose of vaccines for those with weak immune systems on Thursday, August 12.
The FDA will amend the emergency use authorizations of the two mRNA vaccinations Pfizer/BioNTech, and Moderna to add a third dose for patients with immunocompromised. According to NBC News, this would be the first authorization for a third dose in America.
According to slides of a meeting from the Centers for Disease Control and Prevention (CDC), 2.7% of Americans are immunocompromised. The slides were presented by an advisory committee that met in July to discuss supplemental doses.
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These patients could include people with tumors, HIV, transplants, or who are receiving immune suppressing medication. According to NBC News, it is not clear what conditions will be covered by the authorization for a third dose.
Studies show that people with weaker immune systems are less likely to mount a strong response against SARS/CoV-2 than those who have healthy ones. NBC News reported that 24 patients who had received two doses of mRNA vaccine were able to develop no antibodies against coronavirus. Six others developed weak levels.
According to slides from the advisory committee, those with compromised immune systems are more likely than others to contract COVID-19. They also have a shorter duration of illness, are more likely transmit the virus to their household contacts, and are at greater risk for a breakthrough infection.
According to slides, emerging data shows that an additional dose mRNA vaccine can increase antibody production and increase the number of people who are able to respond to it. According to slides, studies have shown that between one-third to one-half of patients with immunocompromised who did not show an antibody response to the first two doses mRNA vaccines developed a response to the third dose.
According to NBC News, after two weeks of receiving a third dose COVID-19 vaccine, eight of the 24 patients with no antibodies developed antibodies. All six of those with low antibodies showed an increase in their antibody levels.
According to NBC News, after the FDA has amended the authorization, the CDC advisory committee will vote on whether to recommend the third dose to immunocompromised patients.
People who are in the right categories will be permitted to receive the third dose if the advisory committee approves.
Original publication on Live Science