The Food and Drug Administration on Wednesday approved a Covid-19 vaccine being developed by Novavax, a Maryland biotechnology company that received significant federal funding to manufacture the shot. The vaccine will be a new option for Americans as vaccination rates stagnate.
After two years of development, the vaccine has finally overcome manufacturing problems and is the fourth trial to receive approval in the United States. Advisors from the Centers for Disease Control and Prevention are set to meet next week and are expected to discuss who should receive the Novavax vaccine.
The two-dose vaccine has been approved as a primary series for adults and not as a booster, which is likely to initially limit its market. The Biden administration said earlier this week it would buy 3.2 million doses, enough to fully vaccinate 1.6 million people in the United States. Announcing the purchase, the government said Novavax expected to complete its quality testing “in the next few weeks,” a necessary step before the doses are released.
Novavax hopes its vaccine will appeal to people who have spurned the injections from Pfizer-BioNTech and Moderna, which use messenger RNA technology. About 22 percent of people in the United States have not received a single dose of Covid vaccine.
Novavax’s vaccine, given in doses three weeks apart, works differently than mRNA vaccines. It provokes an immune response with nanoparticles composed of proteins from the surface of the coronavirus that causes Covid-19. Similar protein-based vaccines have been used worldwide for decades.
But modest demand for the Novavax shot in other affluent countries leaves it unclear whether the company’s prediction for the United States will hold up. Only 12.6 million Novavax doses were distributed in Europe between December, when the vaccine was approved there, and June 30. In contrast, more than a billion doses of Pfizer-BioNTech and Moderna vaccines have been distributed in Europe.
A Morning Consult poll released earlier this month suggests Novavax may face a similar lack of enthusiasm in the United States. Only 10 percent of the unvaccinated people contacted for the survey said they would definitely or probably receive a protein-based vaccine.
The approval includes a warning that Novavax’s vaccine is associated with an increased but small risk of forms of heart inflammation known as myocarditis and pericarditis. Reviewing Novavax’s data, FDA researchers identified six cases of the side effect in approximately 40,000 study volunteers.
Moderna’s and Pfizer-BioNTech’s mRNA vaccines are also associated with an increased risk of these conditions, but this association only emerged after they were widely used. A risk warning has also been placed on the packaging.
Before the pandemic, Novavax was a little-known biotechnology company with multiple vaccines in the research pipeline but no approved products. It gained notoriety when Operation Warp Speed, the federal government’s 2020 campaign to develop coronavirus vaccines, singled it out for support. The program initially agreed to pay up to $1.6 billion to fund development of the vaccine and to purchase up to 100 million doses of vaccine.
However, a series of manufacturing delays meant the shot was unavailable for the first wave of vaccines in the United States in early 2021.
Production problems continued to haunt the company. Even after an FDA advisory committee recommended approval of the vaccine in early June, it took the agency weeks to give it the green light because more time was needed to approve Novavax’s manufacturing process. The Serum Institute of India, the world’s largest vaccine manufacturer, makes Novavax’s vaccine.
In a series of clinical studies, Novavax found that its vaccine offered a high level of protection against symptomatic infections. But the original formulation is probably not as effective against the Omicron variant, which emerged in November and bypassed some of the protection offered by other companies’ approved vaccines.
Novavax is developing new versions of its vaccine that target Omicron and its highly contagious subvariants. Preliminary data from laboratory and animal studies indicate that a booster dose targeting an earlier Omicron subvariant, BA.1, elicits strong immune responses to the virus. The company expects to get results from a clinical trial on this shot in September, with doses ready in the last three months of this year.
The company plans to accelerate its research into recordings specifically tailored for two newer versions of Omicron, known as the BA.4 and BA.5.
Trials have also shown that Novavax’s shot works well as a booster shot, and the company is expected to apply for booster shot approval soon. The company may then be able to attract vaccinees who wish to switch to a new option to protect against new variants.
John Moore, a virologist at Weill Cornell, said he thinks Novavax is an excellent vaccine but isn’t yet convinced that an Omicron-based booster would offer much additional protection compared to the original version. “There is too little information,” he said.
dr Moore speculated that some people might switch to Novavax for a booster shot this fall because it caused relatively few cases of pain, fatigue, and other transient side effects in clinical trials. That was his experience as a volunteer in one of Novavax’s studies. “The only way I could tell the next day which arm I had the needle in was the patch,” he said.
If Novavax is approved for a booster dose, Dr. Happy to return to Moore for another injection, he said, “Sometime in the fall I’m going to get another dose, and it would be Novavax.”