The US Food and Drug Administration has authorized a third dose of COVID-19 vaccines by Pfizer Inc -BioNTech and Moderna Inc for people with compromised immune systems.
The amended emergency use authorization on Thursday paves the way for people who have had an organ transplant, or those with a similar level of weakened immune system, to get an extra dose. The patients may consult with their doctor to see if they are eligible, FDA spokesperson Abby Capobianco said.
"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," Janet Woodcock, US FDA's acting commissioner, said in a tweet on Thursday.
Others who are fully vaccinated are adequately protected & do not need an additional dose of #COVID19 vaccine at this time. 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.
— Dr. Janet Woodcock (@DrWoodcockFDA) August 13, 2021
"Others who are fully vaccinated are adequately protected & do not need an additional dose of COVID-19 vaccine at this time."
The vulnerable group makes up less than 3% of US adults, Rochelle Walensky, director of the Centers for Disease Control and Prevention (CDC), had said before the authorization.
Supporting the move to approve an additional shot, Paul Offit, director of the Vaccine Education Center at Children's Hospital of Philadelphia, said it would be important for the CDC to provide clear recommendations about who should receive it.
"Most clinicians are not going to know what an equivalent level of compromise is for solid organ transplant patients... hopefully the CDC will be more specific about that... (and) whether or not therapies can be manipulated so you can give your patient an optimal chance of having an immune response."
A panel of advisers to the CDC will meet on Friday to discuss booster doses, and a vote later by the committee will help decide on the rollout of the extra shots.
BOOSTERS FOR YOUNG, HEALTHY
Scientists are still divided over the broad use of COVID-19 vaccine boosters among those without underlying problems as benefits of the boosters remain undetermined.
Pfizer has said the efficacy of the vaccine it developed with partner BioNTech drops over time, citing a study that showed 84% effectiveness from a peak of 96% four months after a second dose.
Moderna has also said it sees the eventual need for booster doses, especially since the Delta variant has caused "breakthrough" infections in fully vaccinated people.
Reports of infections among vaccinated people and concerns about diminishing protection have galvanized wealthy nations to distribute booster shots, even as many countries struggle to access first vaccine doses.
The World Health Organization last week called for a moratorium on COVID-19 vaccine booster shots until at least the end of September.
"We think other countries might also follow suite, despite WHO's concerns for vaccine equity, due to the rising health risks posed by the Delta variant and diminishing protection of the vaccine over time," CFRA Research analyst Sel Hardy said.
Wall Street analysts expect the authorization of a booster dose for a broad population to bolster profits of COVID-19 vaccine makers.
Shares of Pfizer, Moderna and US-listed shares of BioNTech rose between 1% and 2% in early trading.