New FDA rules: Easier Covid vaccine access for vulnerable, tougher for healthy

Healthy Americans may soon find it harder to get Covid-19 boosters in future as the FDA now demands stronger clinical proof of effectiveness before approving shots for those without risk factors.

The US Food and Drug Administration (FDA) is overhauling how it approves Covid-19 vaccines and is introducing stricter requirements for healthy people while easing access for those at higher risk of serious illness, Dr. Vinay Prasad, the new director of the FDA’s Center for Biologics Evaluation and Research, and FDA Commissioner Dr. Marty Makary, said in an editorial published Tuesday in the New England Journal of Medicine.The move could significantly limit vaccine availability for millions of Americans who were previously eligible.

Under the updated guidelines, future Covid-19 booster shots will likely be available in the fall to adults aged 65 and older, as well as to people as young as 6 months who have medical conditions that increase their risk of severe illness. For these groups, vaccine makers will only need to demonstrate that a shot generates strong antibody responses, a type of study known as immunobridging.

What is immunobridging

They are usually done in a smaller number of people, and quite quickly so that in case an expects wave of disease hits, the vaccine manufacturing can increase the production in time to have large numbers of shots ready.

This method is similar to how seasonal flu vaccines are approved each year and continues a practice the FDA has already been following with Covid-19 shots in recent years.

'No clear evidence of healthy individuals getting benefitted from Covid shots'

According to the study, there’s no enough evidence that healthy kids and adults get clinically meaningful benefit from regular Covid-19 shots. They want to see placebo-controlled trials, particularly in adults ages 50 to 64, before recommending the shots for other groups.

Dr. Noel Brewer, a professor of public health and health behavior at the University of North Carolina at Chapel Hill and a member of the CDC’s Advisory Committee on Immunization Practices, supports the FDA’s revised approach.

“The proposed policy moves the US in line with other countries. This global view of public health is a welcome development,” Brewer, who sits on the CDC’s Advisory Committee on Immunization Practices, and was part of the working group mulling the change to Covid vaccine recommendations, was quoted as saying by CNN.

How the move will affect vaccine eligibility for Americans

In the new framework, the bar will be higher for healthy individuals aged 6 months to 64 years with no risk factors. For them, the FDA will require randomized, placebo-controlled trials that show the vaccine not only boosts antibodies but also prevents symptomatic Covid-19. The agency will also consider secondary outcomes such as reductions in severe illness, hospitalization, and death.

The change would mean that millions of healthy adults and children may no longer qualify for updated Covid-19 shots, barring stronger evidence from manufacturers. The authors of the study argue that current data does not support regular Covid-19 vaccination for healthy individuals in terms of meaningful clinical benefits.

Long Covid not factored into the new study

FDA's updated criteria doesn't mention long Covid, a lingering set of symptoms that can affect people for months after infection. Research has shown that vaccination can reduce the risk of long Covid by 25% to 60%, but this factor will not influence approval decisions under the new framework.

Prasad and Makary say their approach is to protect the most vulnerable while restoring public confidence in the vaccine approval process. They noted that nearly three-quarters of Americans aged 6 months and older have an underlying condition that qualifies them as high-risk under CDC definitions.

The authors say millions of Americans under 65 will still qualify to get a Covid-19 vaccine if they want one if they have any of a broad range of health conditions identified by the CDC as putting a person at high risk of severe disease from Covid-19.

“Estimates suggest that 100 million to 200 million Americans will have access to vaccines in this manner,” the FDA officials wrote.