WASHINGTON (AP) – While many Americans who have received Pfizer vaccines are already rolling up their sleeves for a booster, millions more who have received the Moderna or Johnson & Johnson vaccine are anxiously waiting to know when it’s their turn .
Federal regulators are starting to tackle this issue this week.
On Thursday and Friday, the Food and Drug Administration summons its independent advisers for the first step in the process of deciding whether additional doses of the two vaccines should be distributed and, if so, who should get them and when. The final green light is not expected for at least a week.
Once FDA advisers have given their recommendation, the agency itself will make a formal decision on whether or not to authorize boosters. Then next week, a panel convened by the Centers for Disease Control and Prevention will offer more details on who should get them. Its decision is subject to the approval of the director of the CDC.
The process aims to build public confidence in the safety and efficacy of vaccines. But this has already led to conflicts and disagreements between various experts and agencies.
For example, last month, the CDC’s advisory committee backed Pfizer six-month boosters for older Americans, nursing home residents, and people with underlying health conditions. But CDC director Dr Rochelle Walensky canceled her advisers and ruled that recalls should also be offered to people in high-risk jobs such as teachers and healthcare workers, adding tens of millions of dollars. Americans added to the list.
Some health experts fear the back-and-forth deliberations will scramble public efforts to persuade the unvaccinated to get vaccinated for the first time. They worry that the booster talk will lead people to mistakenly doubt the effectiveness of vaccines in the first place.
As the FDA panel of experts meets to review Moderna and J&J vaccines, its decisions this time will likely be even more complicated, with experts questioning whether a third injection of Moderna should only contain half the dose of origin and when is the best time for a second injection of the single-dose J&J vaccine.
The panel will also examine the safety and effectiveness of mixing and pairing different brands of vaccines, which regulators have yet to approve.
An estimated 103 million Americans are fully vaccinated with Pfizer’s formula, 69 million with Moderna and 15 million with J&J, according to the CDC.
The two initial injections of Moderna each contain 100 micrograms of the vaccine. But the drugmaker says 50 micrograms should be enough for a booster for healthy people.
A company study of 344 people gave them a 50 microgram injection six months after their second dose, and anti-virus antibody levels jumped. Moderna said the booster even triggered a 42-fold increase in antibodies capable of targeting the extra-contagious delta variant.
The side effects were similar to the fevers and pain that Moderna recipients typically experience after their second regular injection, the company said.
As for people who received the J&J vaccine, the company has submitted data to the FDA for different options: a two-month booster or a six-month booster. The company did not indicate its preference.
J&J released data in September showing that a booster given at two months offered 94% protection against moderate to severe COVID-19 infection. The company has yet to disclose patient data on a six-month booster, but early measurements of anti-virus antibodies suggest it offers even greater protection.
Even without a booster, says J&J, his vaccine remains around 80% effective in preventing COVID-19 hospitalizations in the United States
Scientists point out that the three vaccines used in the United States still offer strong protection against serious illness and death from COVID-19. The problem is how quickly and to what extent the protection against a milder infection can decrease.
In a recent study, researchers compared around 14,000 people who received their first dose of Moderna a year ago with 11,000 vaccinated eight months ago. While the delta variant increased in July and August, the most recently vaccinated group had a 36% lower rate of “breakthrough” infections compared to those vaccinated longer ago.
Yet medical experts continue to debate the science and the rationale for giving extra injections to those who already have significant protection.
The White House and its top medical advisers in August announced ambitious plans to offer reminders to almost all adults, citing signs of declining protection and the then-booming Delta variant. But they were rebuffed by many experts who said there is little data showing whether such broad use would stop breakthrough infections or slow the overall trajectory of cases.
While the FDA and CDC ultimately cut back on the use of Pfizer boosters, Biden administration officials, including Dr.Anthony Fauci, suggested that additional injections would eventually be recommended for most Americans.
They point to data from Israel showing lower rates of infections and serious illnesses in people who received a third injection of Pfizer.
The FDA meetings come as U.S. vaccinations have climbed above 1 million per day on average, an increase of more than 50% in the past two weeks. The increase is mainly due to recalls from Pfizer and vaccination mandates from employers.
The Associated Press’s Department of Health and Science receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.