FDA Authorizes Updated Moderna and Pfizer Booster Shots

The Food and Drug Administration (FDA) today authorized reformulated versions of the Pfizer and Moderna COVID-19 boosters in a bid to broaden Americans’ protection against a potential winter surge.

If the Centers for Disease and Prevention signs off on the recommendation, the shot will be available shortly after Labor Day.

Individuals 12 years and older are eligible for the new Pfizer booster dose if their most recent shot was at least two months ago. The same two-month interval is recommended for Moderna's booster shot, but it is currently limited to people 18 and above.

The new booster vaccine will be bivalent, meaning it will protect against the original COVID-19 as well as the newer Omicron subvariants, such as BA.4 and BA.5. It will be available as a booster shot, but not a primary series.

The FDA decision is based largely on animal studies of the new formula and existing data on the original version of the vaccine, since it can take months to do the clinical trials that are typically required to authorize a new vaccine formula.

"As we head into fall and begin to spend more time indoors, we strongly encourage anyone who is eligible to consider receiving a booster dose with a bivalent COVID-19 vaccine to provide better protection against currently circulating variants," FDA Commissioner Robert M. Califf, MD, said in a statement.

A panel of CDC advisers will meet on September 1 and 2 to discuss the clinical considerations.

Will Bivalent Boosters Offer Long-term Protection?

At an FDA committee meeting in June, most panelists agreed that a bivalent vaccine involving BA.4 and BA.5 components is necessary.

BA.5 now accounts for nearly 90% of COVID-19 cases in the United States. But the virus mutates quickly, and each iteration tends to be more transmissible than the last. The booster strategy is an attempt to get ahead of new mutations that may pop up in the coming months.

The FDA said it had long expected that vaccines may need to be modified to address new variants and that enough is now known about how the mRNA vaccine technologies by Pfizer and Moderna work to expect the shots to be safe.

Pfizer and Moderna had already collected clinical trial data on a vaccine made to protect against the earlier Omicron strains, and the FDA said it considered that data when choosing to authorize the retooled boosters.

By seeking authorization before clinical trials are finished, Pfizer is betting it can get the vaccine to people before new viral mutations render the shots ineffective.

Although cases and hospitalizations are declining, an average of 400 people in the U.S. are dying every day of COVID-19, per the CDC.

Of people who have received the full COVID-19 primary series, fewer than half have gotten their first booster. Only about a third of adults older than 50 have received their second booster.

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.