merican adults who haven’t yet gotten vaccinated against COVID-19 may soon get another choice, as advisers to the Food and Drug Administration on Tuesday backed a more traditional type of shot.
Next, the FDA must decide whether to authorize the protein vaccine made by latecomer Novavax as the nation’s fourth coronavirus shot for adults. It’s made with more conventional technology than today’s dominant Pfizer and Moderna shots and the lesser-used Johnson & Johnson option.
Novavax shots can already be purchased in Australia and Canada as well as parts of Europe. U.S. clearance remains a significant hurdle for the Maryland-based firm.
FDA’s vaccine chief Dr. Peter Marks said another choice in the U.S. may entice at least some vaccine holdouts—whatever their reason—to consider rolling up their sleeves.
“We do have a problem with vaccine uptake that is very serious in the United States,” Marks said. “Anything we can do to get people more comfortable to accept these potentially life-saving products is something that we feel we are compelled to do.”
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A final FDA decision isn’t expected immediately, as the agency finishes combing through the data.
It is not clear, however, how widespread a Novavax vaccination would be spread. According to the Centers for Disease Control and Prevention, only 27 million Americans are still unvaccinated. Eventually, Novavax hopes also to become a choice for the millions more who haven’t yet had a booster dose of today’s vaccines, regardless of which shot people got originally.
The FDA advisory panel voted that the benefits of two primary Novavax doses outweigh its risks—but they had a lot of questions about the shots’ role at this point in the pandemic.
“This vaccine does indeed fill some unmet needs,” such as an option for people with allergies to competing shots, said Dr. Michael Nelson of the University of Virginia.
He said that the FDA will consider two doses of adult vaccines, while other COVID-19 vaccinations would have required a third.
And while “this vaccine has incredible potential,” there’s no clear evidence yet of how well it works against the more contagious omicron variant and its siblings, added fellow adviser Dr. Bruce Gellin of the Rockefeller Foundation.
Two doses of Novavax were found to be safe in large studies done in Britain, Mexico, and the U.S. and approximately 90% effective for symptomatic COVID-19. There was one problem: These studies were performed much earlier during the pandemic.
Novavax Chief Medical Officer Dr. Filip Dubovsky stated that boosters of the vaccine have shown that they boost virus-fighting antibodies. This could help to combat the omicron mutation. FDA will need to review this data.
This type of vaccine “we think generates a broad immune response against a broad array of variants,” he told the FDA advisory panel.
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The FDA noted that most participants in trials experienced no severe reactions other than minor discomforts like pain and fatigue at the injection sites. However, six cases of myocarditis, which is heart inflammation, were found in the study population.
Following the Pfizer Moderna and Pfizer shots that were associated with this rare risk, COVID-19 vaccinations are being closely examined for heart inflammation.
Novavax suggested that there could be other causes. COVID-19, another infection that can lead to heart inflammation, is also possible. The company said more than 744,000 vaccinations in other countries so far support the shots’ safety.
Several of FDA’s advisers said the Novavax vaccine should come with a warning until more is known but cautioned against comparisons with the Pfizer and Moderna shots’ estimated rate of the rare side effect.
“I don’t want to stigmatize this vaccine inappropriately,” said Dr. Cody Meissner of Tufts University.
Novavax is made from copies of coronavirus spike protein, which are packaged in nanoparticles to look like viruses. Then an immune-boosting ingredient, or adjuvant, that’s made from the bark of a South American tree is added that acts as a red flag to ensure those particles look suspicious enough to spark a strong immune response.
Since years, proteins vaccines have been used to treat shingles, hepatitis B, and other diseases.
That’s very different than the vaccines currently used in the U.S. Moderna and Pfizer are two of the most well-known vaccines. These provide instructions genetically to allow the body’s production of spike protein. J&J uses a cold virus to deliver those instructions.
Manufacturing problems held up Novavax’s vaccine but the company said those problems have been resolved. Novavax is a biotech startup that created the vaccine at its own research laboratory. But the Serum Institute of India, the world’s largest vaccine maker, produces most of its shots including those slated for the U.S.
The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. All content remains the responsibility of the Associated Press.
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