FDA Advisers Consider Novavax COVID-19 Vaccine This Week

Carolyn Crist

June 06, 2022

The FDA's vaccine advisors are scheduled to meet on Tuesday to consider authorizing the Novavax COVID-19 vaccine.

The committee will vote on whether the benefits of the two-dose vaccine outweigh the risks for ages 18 and older, according to the 80-page briefing document posted Friday.

Based on data included in the document, an FDA review found that the vaccine's effectiveness was 90.4% overall against mild, moderate, or severe COVID-19 for about 2.5 months after completing the two doses. For adults 65 and older, effectiveness fell to 78.6%.

These numbers were collected before the emergence of the Omicron variant, according to CNN. It remains unclear how effective the vaccine is or how long protection lasts against the most recent subvariants.

Novavax has reported that its vaccine has "broad cross-creativity against Omicron and other circulating variants from a primary 2-dose regimen, with responses that increased following a third dose at six months," according to an announcement released in late December.

The FDA will also consider reports of adverse reactions to the Novavax vaccine, including fatigue, headaches, muscle aches, and pain at the injection site. Most reports were of mild to moderate reactions that lasted a few days. However, the FDA described rare events of myocarditis and pericarditis, which involve inflammation of the heart muscle and tissue surrounding the heart.

The briefing document describes six cases of myocarditis or pericarditis that happened after the Novavax vaccine. Five were among males between ages 16-67. Among the six cases, five were hospitalized but have now recovered.

Novavax addressed the heart inflammation concerns in a statement on Friday, saying that the rate of myocarditis is "within the expected rate" and similar to the groups that received a placebo. The company added there is "insufficient evidence" to establish a causal relationship between the vaccine and myocarditis or pericarditis.

"We have learned that we can expect to see natural background events of myocarditis in any sufficiently large database, and that young males are at higher risk," the company said. "Myocarditis is most often caused by nonspecific viral infections."

In the FDA briefing document, the agency summarized that the "known benefits" among Novavax vaccine recipients relative to the placebo include a "reduction in the risk of mild to severe COVID-19 occurring at least 7 days after the second primary series vaccination." The committee meeting will take place online, and people can watch a live broadcast on the FDA website or YouTube.

Novavax submitted its application for FDA authorization in late January, CNN reported. Indonesia was the first country to grant emergency use authorization of the Novavax vaccine in November, which was followed by the European Union, United Kingdom, Canada, Austria, India, New Zealand, South Korea, and the Philippines.

Although most adults in the U.S. have already been vaccinated against the coronavirus, the Novavax vaccine is seen as a potential option for booster doses, regardless of the primary vaccine series that someone received.

In addition, the vaccine is seen as another option for those who remain unvaccinated. Novavax developed a protein subunit vaccine, which is a more traditional type than the mRNA technology used for the Moderna and Pfizer shots. Other well-known subunit vaccines include the hepatitis B and pertussis vaccines, CNN reported.

Protein-based vaccines prompt the body's immune system to recognize modified pieces of the virus, CNN reported. For the Novavax vaccine, that means pieces of the spike protein on the coronavirus.

"We believe our vaccine offers a differentiated option built on a well-understood protein-based vaccine platform that can be an alternative to the portfolio of available vaccines to help fight the COVID-19 pandemic," Stanley Erck, Novavax CEO, said in a statement in January.

Novavax is also studying a separate vaccine that specifically targets the Omicron variant. The company announced last week that a Phase 3 clinical trial has begun that will include 1,340 participants in Australia. The vaccine is being tested as a booster shot for those who previously received mRNA vaccines.

The trial will last 10 months, and the initial results are expected in the "second half of 2022," the company said in a statement.


FDA: "Vaccines and Related Biological Products Advisory Committee Meeting, June 7, 2022 FDA Briefing Document, Novavax COVID-19 Vaccine."

CNN: "FDA advisers to weigh risks and benefits of Novavax's Covid-19 vaccine."

Novavax: "Novavax Announces Initial Omicron Cross-Reactivity Data from COVID-19 Vaccine Booster and Adolescent Studies." "Novavax Statement on US FDA Briefing Document Related to Myocarditis/Pericarditis." "Novavax Submits Request to the U.S. FDA for Emergency Use Authorization of COVID-19 Vaccine." "Novavax Initiates Phase 3 Trial of its COVID-19 Omicron Strain Vaccine as a Booster."


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.