U.S. adults who haven’t gotten any COVID-19 shots yet should consider a new option from Novavax—a more traditional kind of vaccine, health officials said Tuesday.
Regulators authorized the nation’s first so-called protein vaccine against COVID-19 last week, 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 statement, endorsing an earlier decision from an influential advisory panel.
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.
Novavax is different
All of the vaccines used in the U.S. train the body to fight the coronavirus by recognizing its outer coating, the spike protein—and the first three options essentially turn people’s cells into a temporary vaccine factory. Moderna and Pfizer vaccines give genetic instructions that instruct the body how to produce copies of the spike proteins. The lesser-used Johnson & Johnson option uses a cold virus to deliver those instructions.
Novavax vaccine injections spike protein copies that were grown in a lab. These nanoparticles are then injected into the body to mimic 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.
To prevent other diseases, such as hepatitis B (shingles) and protein vaccines (porcine vaccines), they have been around for many years.
In large clinical trials in Britain, Mexico and the U.S. it was found that two Novavax doses were effective and safe for symptomatic COVID-19. Novavax announced a booster dose that boosted virus-fighting antibodies to combat the mutant delta variant when it was first discovered last summer.
The typical reactions to vaccines were not severe, with arm pain and fatigue. However, regulators cautioned about the possible risk of developing heart disease. Heart inflammation is a rare risk that has been observed mostly among teenage boys and young adults who have received the Moderna or Pfizer vaccines.
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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. The booster dose also boosted cross-protective antibody production.
Novavax shot instructions
The CDC’s advisers unanimously endorsed the two-shot primary series. However, many noted the importance of regulators clearing a booster before Novavax recipients need it, approximately five to six months after they last received one.
The two doses are usually given at least three weeks apart. But CDC officials said that like with other COVID-19 vaccines, it’s possible to wait up to eight weeks for the second dose—except for people at the highest risk, who need protection quickly.
The next step
Walensky consented to recommendations for adult Novavax dosages. U.S. Government purchased 3.2 million Novavax doses as its first purchase. The next several weeks will see vaccinations begin.
Novavax is also available in Europe, Canada and Australia. Many countries permit booster doses. European regulators approved the shot to be administered as early as 12 years old.
The Maryland-based firm expects U.S. approval of the booster dose as well as teen vaccines very soon.
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.
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