US grapples with whether to modify COVID vaccine for fall
U.S. health authorities are facing a critical decision: whether to offer new COVID-19 booster shots this fall that are modified to better match recent changes of the shape-shifting coronavirus.
Moderna and Pfizer have tested updated shots against the super-contagious omicron variant, and advisers to the Food and Drug Administration will debate Tuesday if it’s time to make a switch — setting the stage for similar moves by other countries.
“This is science at its toughest,” FDA vaccine chief Dr. Peter Marks told The Associated Press, adding that a final decision is expected within days of the advisory panel's recommendation.
Current COVID-19 vaccines saved millions of lives around the world in just their first year of use. And the Moderna and Pfizer shots still offer strong protection against the worst outcomes -- severe illness and death — especially after a booster dose.
But those vaccines target the original coronavirus strain and between waning immunity and a relentless barrage of variants, protection against infections has dropped markedly. The challenge is deciding if tweaked boosters offer a good chance of blunting another surge when there's no way to predict which mutant will be the main threat.
In an analysis prepared for Tuesday's meeting, FDA officials acknowledged targeting last winter's version of omicron is “somewhat outdated" since it already has been replaced by its even more contagious relatives.
“We would obviously like to get it right enough," Marks said, so that with one more shot “we get a full season of protection.”
Many experts say updated boosters promise at least a little more benefit.
“It is more likely to be helpful” than simply giving additional doses of today’s vaccine, said epidemiologist William Hanage of the Harvard T.H. Chan School of...