FDA OKs boosters for Moderna, J&J vaccines; allows people to mix and match vaccines

This July 2020 photo provided by Johnson & Johnson shows a vial of the COVID-19 vaccine in Belgium. (J&J photo)

The FDA on Wednesday announced it has authorized boosters for millions more Americans, giving a green light for third shots to people who received the Moderna and J&J vaccines.

The FDA also says is will allow people to mix booster doses.

The FDA decision follows an independent FDA advisory panel’s last week that voted to move forward with Moderna and Johnson & Johnson COVID-19 vaccine boosters.

The panel’s decision on J&J was broader than it was for Moderna and Pfizer as it applies to all J&J recipients 18 and older. The timing is also different: The booster can be administered beginning two months after the first shot.

For the two mRNA vaccines, the panel had agreed they should be authorized for a narrower group: seniors and everyone 18 or older if they have underlying conditions or could be exposed to the virus at work. They also agreed on a timeline of six months after the second shot.

But for the single-shot J&J vaccine, which does not offer as strong protection as the two-shot Pfizer or Moderna vaccines, the panel of independent experts agreed it was appropriate to offer boosters to all recipients and to do so sooner in order to get protection to a comparable level.

The FDA also authorize the mixing and matching of COVID-19 booster doses in an effort to provide flexibility as the campaign for extra shots expands.

Preliminary results from a government study of different booster combinations found an extra dose of any type revs up levels of virus-fighting antibodies regardless of the brand people first received. But recipients of the single-dose J&J vaccination had the most dramatic response — a 76-fold and 35-fold jump in antibody levels, respectively, shortly after either a Moderna or Pfizer booster, compared to a four-fold rise after a second J&J shot.

Allowing mixing and matching could make the task of getting a booster simpler for Americans and allow people who may have had adverse reactions to the initial dose to try a different shot.

(ABC News; Associated Press)