Updated on July 18, 2022.
Novavax’s COVID vaccine has cleared its final hurdle and is now the fourth vaccine available to help protect U.S. adults from the disease. The U.S. Food and Drug Administration’s (FDA) authorized the vaccine for emergency use among those ages 18 and older, following the nearly unanimous vote of its independent vaccine advisory committee. The Centers for Disease Control and Prevention (CDC) signed off on the FDA’s decision, enabling U.S. adults to start receiving the vaccine, which uses a traditional virus-blocking technology.
“Authorizing an additional COVID-19 vaccine expands the available vaccine options for the prevention of COVID-19, including the most severe outcomes that can occur such as hospitalization and death,” said FDA Commissioner Robert M. Califf, MD in a July 13 news release. “COVID-19 vaccines remain the best preventive measure against severe disease caused by COVID-19 and I encourage anyone who is eligible for, but has not yet received a COVID-19 vaccine, to consider doing so.”
Federal regulatory officials examined Phase 3 clinical trial data, involving about 30,000 adults in the United States and Mexico. The February 2022 study, which was published in the New England Journal of Medicine, found the vaccine was safe and 90.4 percent effective against the virus. Commonly reported side effects included headache, nausea, aches, fatigue, and soreness at the injection site—similar to those associated with other COVID vaccines already available in the United States.
Like the Pfizer and Moderna mRNA vaccines, there is some concern about an association between the Novavax vaccine and rare cases of inflammation in the heart muscle (myocarditis) or in the outer lining of the heart (pericarditis). But the committee members noted the vaccine’s benefits outweigh any possible risks.
An FDA summary noted the Novavax vaccine trial data was collected months before the Omicron variant became dominant in the United States. Regulators pointed out, however, that the Novavax data is in line with the initial efficacy rates of both the Pfizer and Moderna vaccines. Research on how the vaccine holds up against current and future variants will also be ongoing.
Unlike the Pfizer and Moderna vaccines, Novavax is not an mRNA vaccine. Now that the FDA's authorization has been approved by the CDC, it is the first protein-based COVID vaccine available. Health officials have suggested this new option may help encourage those who are hesitant to vaccinate due to allergies to the mRNA vaccines or lack of choices to get immunized.
“Novavax COVID-19 Vaccine, Adjuvanted provides another alternative for adults and adds another vaccine to the COVID-19 vaccine supply for the United States,” said Peter Marks, MD, PhD, director of the FDA’s Center for Biologics Evaluation and Research (CBER). “The American public can trust that this vaccine, like all vaccines that are used in the United States, has undergone the FDA’s rigorous and comprehensive scientific and regulatory review.”
How the Novavax vaccine works
The Novavax vaccine is a protein-subunit vaccine, which uses a harmless lab-made version of the virus’s spike protein—the protein on the surface of the virus that allows it to invade cells in the body–to trigger an immune response in the body.
Because protein subunit vaccines use only specific pieces of a virus, they produce a strong immune response to this key protein. The vaccine also contains an adjuvant, which is a substance that helps ensure that the immune system jumps into action and starts making protective antibodies. Protein-subunit vaccines have already been developed to treat other infectious diseases, including HPV, hepatitis B, whooping cough, and shingles.
Like Pfizer and Moderna, the Novavax vaccine is given in two primary doses 21 days apart.
