In an amendment to its emergency use authorization for the Pfizer-BioNTech and Moderna COVID-19 vaccines, the U.S. Food and Drug Administration (FDA) authorized a third dose of the shots for certain immunocompromised individuals.
People who have received solid organ transplants or who are considered to have an equivalent level of immunocompromise due to medical conditions are especially vulnerable to severe COVID-19 infection and may not have gotten adequate protection from the two-dose vaccine regimen. The FDA determined that a third dose may increase protection in these patients, but recommends they continue physical precautions to prevent infection.
Those who are eligible for a booster shot are authorized to receive a third dose at least 28 days following the two-dose regimen of the same vaccine.
"The country has entered yet another wave of the COVID-19 pandemic, and the FDA is especially cognizant that immunocompromised people are particularly at risk for severe disease. After a thorough review of the available data, the FDA determined that this small, vulnerable group may benefit from a third dose of the Pfizer-BioNTech or Moderna vaccines," said acting FDA commissioner Janet Woodcock, MD. "Today's action allows doctors to boost immunity in certain immunocompromised individuals who need extra protection from COVID-19. As we've previously stated, other individuals who are fully vaccinated are adequately protected and do not need an additional dose of COVID-19 vaccine at this time. The FDA is actively engaged in a science-based, rigorous process with our federal partners to consider whether an additional dose may be needed in the future."
Source: FDA press release, August 12, 2021.