Weeks after the Centers for Disease Control and Prevention signed off on Novavax’s two-dose COVID vaccine, the biotechnology company is seeking approval to distribute booster shots.
Novavax announced Monday it submitted an application to the U.S. Food and Drug Administration for Emergency Use Authorization for booster shots of its protein-based vaccine in adults 18 years old and above, according to a news release.
The nation’s first so-called protein vaccine against COVID-19, it was approved by regulators in mid-July, but the final hurdle was a recommendation from the Centers for Disease Control and Prevention.
“If you have been waiting for a COVID-19 vaccine built on a different technology than those previously available, now is the time to join the millions of Americans who have been vaccinated,” Dr. Rochelle Walensky, CDC’s director, said in a previous statement, endorsing an earlier decision from an influential advisory panel.
Since approval of the initial two doses was given, distribution has begun across the U.S.
It’s late in the pandemic for a new choice, but the company is hoping to find a niche among some of the unvaccinated millions who might agree to a more traditional kind of shot — a protein vaccine — and also to become a top choice for boosters, regardless of which type people got first. Only about half of vaccinated adults have gotten a booster.
In contrast to other vaccines, the Novavax vaccine injects copies of the spike protein that are grown in a lab and packaged into nanoparticles that to the immune system resemble a virus. Another difference: An ingredient called an adjuvant, that’s made from the bark of a South American tree, is added to help rev up that immune response.
Protein vaccines have been used for years to prevent other diseases including hepatitis B and shingles.
Most Americans have gotten at least their primary COVID-19 vaccinations by now, but CDC officials said between 26 million and 37 million adults haven’t had a single dose — the population that Novavax, for now, will be targeting.
“We really need to focus on that population,” said CDC adviser Dr. Oliver Brooks, past president of the National Medical Association. Hopefully, the vaccine “will change them over from being unvaccinated to vaccinated.”
While it’s unclear how many will be persuaded by a more conventional option, “I’m really positive about this vaccine,” agreed fellow adviser Dr. Pablo Sanchez of Ohio State University.
Large studies in the U.S., Mexico and Britain found two doses of the Novavax vaccine were safe and about 90% effective at preventing symptomatic COVID-19. When the delta variant emerged last summer, Novavax reported a booster dose revved up virus-fighting antibodies that could tackle that mutant.
Typical vaccine reactions were mild, including arm pain and fatigue, but regulators did warn about the possibility of a rare risk, heart inflammation, that also has been seen with the Pfizer and Moderna vaccines, mostly in teen boys or young men.
But early on, manufacturing problems delayed the Novavax vaccine — meaning the shots were studied long before the omicron variant hit, so it’s not clear how well they hold up against the immune-evading mutant.
Still, Novavax points to lab testing that shows the first two shots do spur production of virus-fighting antibodies that are cross-protective against omicron, including the BA.5 subtype that’s currently the nation’s top threat. A booster dose further revved up cross-protective antibodies.
The Novavax vaccine also is used in Europe, Canada, Australia, South Korea and other countries. Many allow booster doses, and European regulators recently cleared the shots to given as young as age 12.
And like other vaccine makers, Novavax is testing shots updated to better match the newest omicron subtypes — in anticipation of another round of boosters this fall and winter.