Can new COVID vaccine win over the anti-vaxxers?

With three COVID vaccines already authorized by the U.S. Food and Drug Administration, Americans have easy access to plenty of shots.

But a fourth one, under review Tuesday, is entirely different — and uses a traditional vaccine design that more people may be inclined to trust.

The vaccine, made by Novavax, works just as well as the Pfizer and Moderna vaccines, the company’s studies show. Its side effects seem milder. It’s easier to store. At least 41 other countries — including Australia, Canada, South Korea and the 27 members of the European Union — have approved it. And it enlists the same familiar technique as vaccines against flu, diphtheria, tetanus and whooping cough.

“I’m likely going to recommend this for my parents, who are age 84 and 87, for their fifth dose this fall,” said UC San Francisco infectious disease specialist Dr. Monica Gandhi.

It may also bolster immunity when used in combination with existing vaccines, said infectious disease expert Dr. Peter Chin-Hong of UCSF. While not yet proven, the Novavax vaccine’s use as a booster could trigger the production of a broader and more protective array of antibodies, which could help fend off new variants.

“I think it would make good sense to ‘mix and match’ with a completely different type of vaccine,” he said. “It may generate new kinds of antibodies than are in mRNA vaccines.”

On Tuesday, the vaccine must pass a critical milestone when a panel of outside experts will recommend — or reject — that the FDA authorize the vaccine. Data show that Novavax is 96% effective in preventing severe disease or death and 90% protective against infection, comparable to Moderna and Pfizer. This data was collected before the more contagious omicron and its subvariants started widely circulating.

About 40% of people reported fatigue after a second dose of Novavax, compared with 65% for Moderna and more than 55% percent for Pfizer.

But there are concerns about a small number of cases of rare heart inflammation, myocarditis and pericarditis, which caused the biotech company’s share price to plummet 18% on Monday. Similar problems led federal health officials this spring to recommend a pause in the use of Johnson & Johnson’s vaccine.

While the new vaccine’s arrival is too late to make an impact against the deadly early waves of the COVID pandemic, it could make inroads among the unvaccinated. More than three-quarters of Americans age 18 and older are already fully vaccinated. As of Monday morning, the nation’s unofficial toll reached 84,735,800 infections and 1,007,815 deaths — an increase of 213,572 and 616, respectively, from Friday.

“I’ve been waiting for this moment for a long time,” said Heather Schmidt, of Ventura, who is severely allergic to an ingredient in the available vaccines, so is unprotected. “This has been an incredibly stressful couple of years, and I really felt abandoned. I do not understand why every other country has more options than Americans.”

Alan Chase, of Santa Cruz, newly diagnosed with COVID, said, “I’ve been waiting for the Novavax vaccine as my second booster shot. I figured the benefits of mixing and matching vaccines was worth waiting a bit longer. But alas, I waited too long and am now in bed. I’ll still probably get it once available.”

A fourth vaccine could also help control pharmaceutical price excesses, once vaccines are no longer free, said Art Caplan, a bioethicist and the founding director of the division of medical ethics at New York University’s Grossman School of Medicine.

“There’s going to be a need for some competition in the market,” he said.

The Novavax vaccine works by using a telltale piece of the coronavirus: the notorious spike protein. All alone, the spike protein is harmless and can’t cause COVID-19. But when your immune system encounters the protein, it produces antibodies against it. In contrast, the mRNA vaccines work by sending genetic instructions to the body to make copies of part of the spike protein.

The Novavax vaccine offers a shortcut — and a larger piece of the protein.

Because it uses a bigger piece of the spike protein, which may be shared by more variants, it might help protect against newer versions of the evolving virus. Novavax is already designing a vaccine to combat the more infectious subtypes, but clinical data isn’t expected until later this year.

While Novavax will be a late entrant in the U.S. COVID vaccine marketplace, it has found international traction. The Trump administration’s Operation Warp Speed program awarded Novavax a $1.6 billion contract for 100 million future doses, but the company was slow out of the gate. That’s because manufacturer Novavax has little experience in the vaccine field, and its technology takes longer to test. This delayed its review by regulators.

In contrast, rivals Pfizer/BioNTech and Moderna/National Institutes of Health — who had the advantage of experience and powerful partnerships — quickly scored federal approval and now dominate the field. That’s not because their vaccines are better; rather, they better managed their clinical trials. Use of J&J vaccine has been greatly diminished.

Novavax’s inflammation data did not alarm UCSF’s Chin-Hong, who noted that it was also seen in the placebo group and that other nations have not seen any dangerous signs. “I think we need to understand that some more, to identify whether it is causal or not,” he said. “But it doesn’t worry me too much. It seems to be safe and well tolerated.”