The Food and Drug Administration has authorized a fourth Covid vaccine dose for both Pfizer (NYSE: PFE) and Moderna (NASDAQ: PFE), for people 50 years of age and older. The move comes as people fear the spread of an even more contagious variant throughout the U.S., similar to what has occurred in Europe and China.
“Based on an analysis of emerging data, a second booster dose of either the Pfizer-BioNTech or Moderna COVID-19 vaccine could help increase protection levels for these higher-risk individuals,” Dr. Peter Marks, who directs the FDA’s Center for Biologics Evaluation and Research, said in a statement.
The Centers for Disease Control and Prevention must first sign off on the new booster before it becomes available to the public. It is not known when that may happen.
Furthermore, the FDA revealed that it had also authorized a second Pfizer booster shot for people ages 12 and older who have compromised immune systems. A second booster for Moderna was also authorized for adults ages 18 and older with compromised immune systems. The second boosters are set to be administered no sooner than four months from the last shot.
However, it is unknown how long the protection of a second booster will last, and when it is appropriate to get it.
“The ‘when’ is a really difficult part. Ideally, we would time booster doses right before surges but we don’t always know when that’s going to be,” said Dr. William Moss, a vaccine expert at the Johns Hopkins Bloomberg School of Public Health.