The Food and Drug Administration moved to expand its emergency authorization of Pfizer's and Moderna's COVID-19 vaccine booster shots to all adults, the companies announced Friday, as health officials are clamoring to head off a potential new surge of cases this winter.
The Centers for Disease Control and Prevention must also weigh in with its recommendations before third doses can officially be greenlighted under federal supply agreements governing use of the shots. But a growing number of state and local health departments are not waiting and have already announced expanded eligibility on their own.
A panel of the CDC's outside vaccine advisers, the Advisory Committee on Immunization Practices, are scheduled to meet Friday afternoon to vote on updated recommendations.
"Enough is enough. Let's get moving on here. We know what the data are. Let's do it, 18 and above, everybody should get vaccinated, should get boosted," Dr. Anthony Fauci, the president's chief medical adviser, said Wednesday night at a webinar hosted by the group ThisIsOurShot.
Fauci is among a roster of the Biden administration's top doctors who have for months called for booster recommendations to be expanded to all adults, instead of the narrower guidance that currently limits third doses of Pfizer and Moderna to seniors and adults with underlying medical conditions or in "high-risk settings" six months after they were first vaccinated.
All recipients of Johnson & Johnson's Janssen COVID-19 vaccine are already eligible to receive a booster two months after their initial shot.
More than 31 million vaccinated Americans — over 17% of the total vaccinated so far — already have a booster shot, according to the CDC's figures. The average pace of booster shots has slowed in recent weeks, dropping by more than 15% from its peak in late October.
Booster shot proponents have cited growing data from the U.S. and abroad suggesting vaccine effectiveness declines over time against both infections and hospitalizations. In the United Kingdom, researchers at Imperial College London reported this week that booster dose recipients there had a three times lower risk of infection compared to those who had gotten only two doses.
The FDA's outside vaccine advisers earlier this year had initially balked at Pfizer's broad request to authorize boosters for all adults, concerned over the risk of myocarditis — a rare type of heart inflammation linked to the shots in mostly younger, male adults. The FDA authorized Moderna's boosters with similar limits.
However, top FDA officials have pointed to data from countries like Israel that have turned up no evidence of an elevated risk following a third shot of Pfizer's vaccine. Moderna's chief medical officer told reporters last week that the company had seen no reports of myocarditis so far after the rollout of its third shot in other countries.
The FDA decided against convening its own vaccine advisers to discuss whether to authorize Pfizer's and Moderna's requests, a spokesperson said, since officials "concluded that they do not raise questions that would benefit from additional discussion by the members of the committee."
Regardless of the agencies' decision, leaders of several states have pledged to move on their own to allow boosters for all adults as cases and hospitalizations have climbed across the country.
"We're optimistic that the message from Minnesota and many other states has been heard and that the federal government is close to announcing that expansion," Jan Malcolm, Minnesota's top health official, told reporters in a recent press briefing.
Only three jurisdictions are predicted to see a decline in the pace of new hospitalizations over the coming month, according to the CDC's national ensemble forecast. Nationwide, the CDC this week downgraded its deaths outlook for the first time in months, no longer predicting that the rate of the pandemic's toll would "likely decrease" in the coming weeks.
Minnesota ranks among the top 10 states predicted to see the highest hospitalization rates over the coming week.
"I would say that, given the very serious circumstances we are here in Minnesota, we've been communication with our federal partners that we're preparing to move ahead independently this week to expand booster eligibility if there is no action at the federal level, which we definitely hope there will be this week," said Malcolm.