An influential federal advisory panel overwhelmingly rejected a plan Friday to give most Americans Pfizer's COVID-19 booster vaccine, but the panel approved additional shots for those 65 or older. old, or who have a high risk of serious illness.
The vote represents a major blow to President Biden's administration's massive effort to strengthen protections for nearly all Americans in the face of the spread of the highly contagious delta variant.
The decision was made by a committee of outside experts who advise the Food and Drug Administration.
In a surprising development, the panel first rejected, by a vote of 16-2, booster shots for almost the entire population. Members cited a lack of safety data on additional doses and also raised doubts about the value of mass use of the third vaccine, despite focusing on specific groups.
Subsequently, in an 18-0 vote, the panel approved the additional vaccine for certain parts of the American population – specifically, those most at risk from the virus.
That would help save some of the White House campaign, but it would still be a big step back from the administration's grand plan proposed a month ago to provide booster doses of the Pfizer and Moderna vaccines for nearly all Americans, eight months after they received the second dose.
Friday's vote was just the first step. The FDA itself is expected to make a decision on the booster dose in the coming days, though it usually follows the committee's recommendations.
The provision of booster doses is also subject to approval by the Centers for Disease Control and Prevention (CDC). A CDC advisory panel is expected to review the issue on Wednesday. The CDC has said it is considering booster doses for older people, nursing home residents and front-line health care workers, rather than the entire adult population.
Separate FDA and CDC decisions will be needed in order for people who received the Moderna or Johnson & Johnson vaccines to receive the booster dose.
During several hours of heated debate Friday, panel members questioned the value of providing booster doses to nearly the entire population.
"I don't think a booster dose will contribute significantly to controlling the pandemic," said Dr Cody Meissner of Tufts University. "And I think it's important that the main message that we convey is that we have to make it possible for everyone to have two doses."
Dr Amanda Cohn of the Centers for Disease Control and Prevention said: "At this point it is clear that the unvaccinated are driving transmission (of the virus) in the United States."
Scientists inside and outside the government have been divided in recent days over the need for booster doses and who should receive them, and the World Health Organization has strongly opposed rich nations doing a third round of injections when poor countries do not have enough vaccines even for the first round.
While research suggests that immunity levels in those vaccinated decline over time and booster doses can restore it, the Pfizer vaccine is still highly protective against severe disease and death, even in the spread of the highly contagious delta variant.
The sudden turn of events could reinforce recent criticism that President Biden's administration got ahead of the science in its effort. President Joe Biden promised early on that his administration would "follow the science," following revelations of political interference in former President Trump's administration's coronavirus response.
The FDA panel's overwhelming rejection came despite prolonged arguments about the need for booster doses from Pfizer and health officials from Israel, which began offering booster doses to its citizens in July.
Sharon Alroy-Preis of Israel's Ministry of Health said the booster dose improves protection against infection tenfold in people aged 60 and over.
"It's like a fresh vaccine," bringing protection back to original levels and helping Israel "mitigate severe cases in the fourth wave," she said.
And representatives of the Pfizer company argued that it is important to strengthen immunity before the protection against serious diseases begins to weaken. A company study of 44,000 people showed that effectiveness against COVID-19 symptoms was 96% two months after the second dose, but had dropped to 84% after about six months.
Both Pfizer and Israeli representatives faced opposition from panel members. Some expressed skepticism about the relevance of Israel's experience to the US. Another concern was whether third doses would exacerbate serious side effects.
Meissner said he is concerned about additional doses for younger age groups given the risk of heart inflammation seen in younger men after a second dose. While the condition is very rare, he said, it is not clear whether that risk will increase with another dose.
The Pfizer company pointed to Israeli data from nearly 3 million booster doses to suggest that the rates of side effects would be similar to those seen after second doses.
Dr Paul Offit, a vaccine expert at the Children's Hospital of Philadelphia, said he was more likely to support approval of a third dose for adults over 60 or 65, but that he "really has trouble" supporting it. for anyone up to the age of 16.
While an additional vaccine is likely to at least temporarily reduce cases with mild or no symptoms, "the question becomes what its impact will be over the course of the pandemic, as it may not be that much," said Dr. Offit.
President Biden's top health advisers, including the heads of the FDA and CDC, first announced plans for large-scale booster vaccination a month ago, targeting the week of Sept. 20 as a safe start date. But that was before FDA staff scientists had completed their evaluations of the data.
Earlier this week, two of the FDA's top vaccine researchers joined a group of international scientists in publishing an editorial rejecting the need for additional vaccines for healthy people. The scientists said ongoing studies show the vaccines have worked well despite the delta variant.
On Friday, the main American health adviser, Dr. Vivek Murthy said that in announcing its plan for booster doses, President Biden's administration was not trying to pressure regulatory agencies to act, but instead was trying to be transparent with the public and be prepared in case additional doses were gaining approval.
"We have always said that this initial plan would be contingent on the FDA and CDC's independent evaluation," Mr. Murthy said.
President Biden's plan has also raised major ethical concerns about poor parts of the world still seeking vaccines. But the administration has argued that the plan is not an 'us or them' choice, noting that the US is supplying large quantities of vaccines around the globe.
The United States has already approved booster doses from Pfizer and Moderna for certain people with weakened immune systems, such as cancer patients and transplant recipients.
Some Americans, healthy or not, have managed to get the extra dose, in some cases simply by showing up and asking for a shot. And some health systems are already offering extra doses to people at high risk./VOA