Skip to main content

Health library

Back to health library

What to know about the Novavax vaccine

Illustration of a syringe crossing a blue shield. COVID-19 molecules surround the image.

Novavax is a vaccine option for people 12 and older who are looking to get their first two COVID-19 shots.

The U.S. Food and Drug Administration (FDA) granted emergency use authorization (EUA) for the Novavax vaccine, and the Centers for Disease Control and Prevention recommended the shot.

Here are some answers to key questions about the vaccine:

Does Novavax work like the other COVID-19 vaccines?

No. Novavax uses different technology than the Pfizer and Moderna vaccines.

The Pfizer and Moderna vaccines are mRNA vaccines. They use messenger RNA to teach our bodies to make a harmless protein of the coronavirus. This triggers an immune response so that our bodies can fight off the virus in the future.

Novavax uses a piece of the coronavirus spike protein and an ingredient called an adjuvant to build an immune response to COVID-19. The protein is made in insect cells. The adjuvant is made from the soapbark tree.

This type of vaccine has been used for more than 30 years, according to CDC. Vaccines for hepatitis B, the flu and whooping cough also work in this way.

How good is it at preventing COVID-19?

The vaccine was more than 90% effective in preventing COVID-19, including severe illness. In a group of people 65 and older, the vaccine was 78% effective.

The study was conducted before the emergence of the omicron variants that have driven a surge in COVID-19 cases across the country.

Is it safe?

Novavax was studied in tens of thousands of people and found to be safe. The most common side effects were similar to those of other COVID-19 vaccines, including:

  • Fever.
  • Headache.
  • Joint pain.
  • Muscle pain.
  • Pain, redness or swelling at the injection site.
  • Tiredness.
  • Upset stomach.

A few people in the vaccine study developed heart inflammation (myocarditis). This occurred both in people who received the vaccine and those who did not. The risk of myocarditis was very low, according to FDA.

Just like other vaccines, Novavax cannot give you COVID-19.

The vaccine may not be right for everyone, though. For instance, you should not get Novavax if you've ever had a severe allergic reaction to any of its ingredients.

How many shots do you need?

Novavax is given as two injections, three to eight weeks apart. Your healthcare provider can help you decide on the timing that is right for you.

Can I choose Novavax as a booster shot?

CDC recommends a bivalent booster shot, even for most people who chose Novavax for their primary vaccine. But a Novavax booster is available for people 18 and older who:

  • Cannot or choose not to receive the Pfizer or Moderna boosters.
  • Completed their primary vaccine series at least six months ago.
  • Have not received any other COVID-19 boosters.

Talk it over

If you have questions about the Novavax vaccine, talk to your healthcare provider. They can help you understand the risks and benefits.

You can also learn more about COVID-19 and how to protect yourself in our Coronavirus topic center.

Reviewed 5/15/2023

Related stories