A Food and Drug Administration advisory group voted on Thursday to recommend Moderna booster shots for emergency use clearance, bringing millions of Americans closer to eligibility for an additional dose.
The panel, called the Advisory Committee on Vaccines and Related Biologics, voted unanimously to allow the injections. The decision will now rest with the FDA, which is expected to make a final decision in the coming days.
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The panel’s recommendations for the Moderna booster followed the plan established last month for booster injections of the Pfizer-BioNTech vaccine: it would be authorized for adults 65 years of age and older; people in long-term care facilities; people with underlying medical conditions; and people at high risk of exposure to coronavirus due to their work. These people would be eligible at least six months after their second injection.
The booster dose of Moderna would be given as a half dose of 50 micrograms, compared to the original 100 micrograms given in the initial vaccination series. (In contrast, Pfizer’s booster is the same 30 microgram strength as its initial set.)
Jacqueline Miller, head of infectious disease therapeutics at Moderna, said in her presentation to the committee that the company chose the half-dose because they wanted to use the lowest possible dose needed to induce an immune response.
Miller noted that using a lower dose booster has worked well for other vaccines, including the DTaP vaccine, which protects against tetanus, diphtheria and pertussis.
The meeting was less controversial than the group’s discussion last month on Pfizer, when advisers rejected authorization of Pfizer recalls for all adults 18 years and older six months after their initial vaccinations and instead chose to limit it. eligibility.
Data shows that protection against Moderna’s vaccine has weakened: People who were vaccinated earlier in the year were more likely to have a breakthrough infection compared to people who were vaccinated several months later, Miller said. Almost all of these breakthrough infections were caused by the delta variant.
Several of the breakthrough cases were considered serious and there were two deaths.
“We are concerned about the revolutionary disease that we have observed in the participants of the [original clinical trial], and in particular the revolutionary cases that we are starting to see in serious illness in the elderly, ”Miller said.
The booster dose led to higher antibody levels, including antibodies against the delta variant.
Still, a handful of groundbreaking infections – 20 cases – have been reported among those who received a booster.
Dr Doran Fink, deputy director of the FDA’s vaccine division, noted that it is still unclear what levels of antibodies are needed for protection.
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Moderna’s presentation and FDA analysis both found the booster to be safe, although several committee members indicated they wanted to see more safety data from the company.
Side effects of the booster were similar to those seen after the second dose. These include arm pain, fatigue, headaches, and muscle pain.
However, the booster trial did not include enough participants to assess whether the extra dose increased myocarditis risk, Fink said.
Myocarditis, or inflammation of the heart muscle, has been linked to Moderna and Pfizer’s Covid-19 vaccines. The disease is rare and most often seen in men under the age of 30.
Hui-Lee Wong, associate director of innovation at the FDA’s Bureau of Biostatistics and Epidemiology, noted that myocarditis occurred at similar rates after the second doses of Pfizer and Moderna.
In data from Israel, where 3.7 million people received a Pfizer booster, 17 cases of myocarditis were reported, said Dr Sharon Alroy-Preis, director of public health services at Israel’s Ministry of Health, who presented Thursday.
“The rate is really, really low compared to what you would expect if it was the same rate as after the second dose,” she said. “Maybe it’s because we are giving this dose five months or later” instead of giving two doses three weeks apart.
The same group of advisers will meet on Friday to discuss a recall of Johnson & Johnson’s Covid vaccine. It will also examine the results of a National Institutes of Health study on the “mix and match” of Covid vaccines. This study found that giving people who had initially received the Johnson & Johnson vaccine a booster dose of Pfizer or Moderna resulted in a stronger immune response than a second Johnson & Johnson dose.
Next week, a group of advisers from the Centers for Disease Control and Prevention will look into who should get the Moderna and Johnson & Johnson booster shots. If boosters are recommended, CDC director Dr Rochelle Walensky would then sign and the shots could start to take hold.
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