A panel of outside advisors to the Food and Drug Administration unanimously recommended a booster shot for seniors as well as younger adults who have other health issues or live in situations that increase their risk of COVID-19.
Although the recommendation is not binding, it is a crucial step towards expanding the U.S. booster program to millions more Americans. Many people who received their first Pfizer shot at least six months ago now have a booster. This is the same group that FDA advisers recommended should receive a Moderna booster.
The panel said there is no evidence to suggest that booster doses of the Moderna and Pfizer vaccines should be opened to everyone, despite initial Biden administration plans.
Unvaccinated individuals are still at risk from the coronavirus, while those who have been vaccinated are protected against serious illness and death by COVID-19.
Dr. Michael Kurilla of National Institutes of Health stated that he doesn't see the need for an "let it rip" campaign for everyone.
The dose of Moderna vaccine is two 100-microgram shots. Moderna suggests that a booster should consist of one 50-microgram shot.
The agency convened experts to discuss who should receive boosters and when. On Friday, the panel will be discussing J&J.
In making final decisions about boosters from both companies, the FDA will consider the recommendations of its advisors. Even if the FDA makes a positive decision next week, there is still one hurdle. A panel that will be convened by Centers for Disease Control and Prevention next week will provide more details on who should receive one.
Scientists in the United States are divided on who boosters should be used and what their purpose is. They can either be used to treat milder infections or for those at high risk of severe illness.
The FDA panel debated whether Moderna provided enough evidence to support its low-dose booster.
Moderna found that people who had been vaccinated more recently experienced a 36% decrease in the rate of "breakthrough" infection, as compared to those who were vaccinated earlier.
A third study, which involved 344 participants, found that a 6-month booster shot could restore virus-fighting antibodies levels to levels believed to be protective. This included large increases in antibodies that can target the delta variant. However, this was a small study and only half of the people who participated received the exact doses offered by Moderna booster campaigns.
Dr. Patrick Moore, University of Pittsburgh, stated that although the data isn't strong, it is definitely moving in the right direction to support this vote.
Many advisers were concerned that people might lose some of the benefits of taking a third shot at full strength if they take a lower dose.
Kurilla stated that this could have a significant impact on durability.
Moderna stated that it selected the lower dose booster due to the fact that it caused fewer unpleasant shot reactions like fever and achiness, but it also left more vaccine for global supply.
Heart inflammation is a rare side effect of the Moderna and Pfizer vaccinations. This is especially true for young men who received their second dose. One question that remains is whether or not another dose might be necessary. Moderna's booster trial was not large enough to detect such a rare risk.
Israel started offering Pfizer boosters earlier than the U.S., and to a larger proportion of its people. Thursday's FDA panel hearing was given by Dr. Sharon Alroy Preis, a doctor from Israel's health ministry. She stated that after administering 3.7 million booster doses, there is no indication that the additional shot is more risky.
The Moderna vaccine is very similar so FDA advisers found this data to be reassuring.
Although Pfizer boosters are limited to certain high-risk Americans, Israeli officials credit greater booster use in their country for stemming the Delta surge.
Alroy-Preis stated, "There is no doubt in my mind that this break of the curve was caused by the booster dose." He responded to FDA advisers, who pointed out that countries other than the United States have experienced a decrease in delta cases.
FDA advisers pointed out a confusing fact: People with severely compromised immune systems can receive a third dose of Moderna vaccine within a matter of hours after their initial shots. The question that remains is whether or not they are eligible for a booster.