Novavax COVID-19 shots get FDA advisory backing as fourth US option for adults

Washington: American adults who have not yet been vaccinated against COVID-19 may soon have another option, as Food and Drug Administration advisors on Tuesday favored a more traditional type of shot. Next, the FDA will have to decide whether to authorize the protein vaccine made by latecomer Novavax as the nation’s fourth coronavirus shot for adults. It is made with more traditional technology than today’s flagship Pfizer and Modern shots and the less used Johnson & Johnson alternative.

Novavax shots are already available in Australia, Canada, parts of Europe and many other countries, either for initial vaccination or as mix-and-match boosters. But US clearance remains a major hurdle for the Maryland-based company. Another option in the US could tempt at least some vaccine holdouts – whatever their reason – to consider rolling up their sleeves, said Dr Peter Marks, the FDA’s vaccine chief.

“We have a problem with getting the vaccine which is very serious in the United States,” Marks said. “Everything we can do to make people more comfortable accepting these potentially life-saving products is something we feel we are compelled to do.” A final FDA decision is not immediately expected, as the agency sifts through the data.

Nor is it clear how widely the Novavax vaccine will be used, at least immediately. According to the Centers for Disease Control and Prevention, only about 27 million American adults remain uninsured.

Eventually, Novavax hopes to become an option even for the millions of people who haven’t yet received booster doses of today’s vaccines, regardless of the shots people originally got. The FDA advisory panel voted that the benefits of the two primary Novavax doses outweigh its risks, but they had lots of questions about the shots’ role at this point in the pandemic.

“This vaccine actually addresses some unmet needs,” said Dr. Michael Nelson of the University of Virginia, “such as an option for people allergic to competitive shots.”
But the FDA is considering two adult doses for now, when other COVID-19 vaccines require a third dose, he said.

And while “this vaccine has incredible potential,” said Dr. Bruce Glynn, a fellow adviser to the Rockefeller Foundation, there’s no clear evidence yet as to how well it works against the more infectious Omicron variant and its siblings.

Large studies in the US, Mexico and the UK found that two doses of the Novavax vaccine were safe and effective in preventing about 90% of symptomatic COVID-19. One complication: Those studies were done much earlier in the pandemic.

Novavax’s chief medical officer, Dr. Philip Dubowski, said the booster dose trial has revealed virus-fighting antibodies that can tackle the Omicron mutants, data that the FDA will have to consider later.

This type of vaccine “we think generates a broader immune response against a variety of forms,” ​​he told the FDA advisory panel. Trial participants typically experienced mild reactions such as injection-site pain or fatigue, but the FDA highlighted a potential concern: Six cases of heart inflammation, known as myocarditis, were reported in the study receiving the vaccine. were found in 40,000 people.

COVID-19 vaccines for the potential for heart inflammation are coming under closer scrutiny after Pfizer and Moderna shots were linked to that rare risk. Novavax argued that there were other possible reasons for the report. Other infections, including COVID-19, can also cause inflammation of the heart.

So far, more than 744,000 vaccination shots in other countries support the safety of the shots, the company said. Several FDA advisors said the Novavax vaccine should come with a caveat until more is known, but cautioned against comparisons with the estimated rate of rare side effects of the Pfizer and Moderna shots. “I don’t want to unduly stigmatize this vaccine,” said Dr. Cody Meisner of Tufts University.

The Novavax vaccine is made from copies of the spike protein that coats the coronavirus, packaged in nanoparticles that resemble a virus in the immune system. Then there’s an immune-boosting ingredient, or adjuvant, made from the bark of a South American tree, which acts as a red flag to make sure those particles are there to spark a strong immune response. Looks suspicious enough.

Protein vaccines have been used for years to prevent hepatitis B, shingles, and other diseases. This is very different from the vaccines currently used in the US.
The most widely used Pfizer and Moderna vaccines give the body genetic instructions to make its own copies of the spike protein. J&J uses a cold virus to deliver those instructions.

Manufacturing problems stalled Novavax’s vaccine, but the company said those problems had been resolved. A small biotech company, Novavax, has made the vaccine in its research lab. But Serum Institute of India, the world’s largest vaccine maker, produces most of its shots, including those slated for the US.