July 25, 2022, 3:57 p.m. Michael Devitt — Family physicians will soon have the option of offering their patients a new COVID-19 vaccine.
On July 19, CDC Director Rochelle Walensky, M.D., endorsed a recommendation from the agency’s Advisory Committee on Immunization Practices for use of the Novavax COVID-19 vaccine in individuals 18 and older.
Earlier that day, the ACIP voted unanimously to recommend use of the vaccine as a primary series in adults, providing an alternative for millions of people who have expressed concerns about receiving an mRNA-based COVID-19 vaccine or who may be allergic to a component in the mRNA vaccines.
“Today, we have expanded the options available to adults in the U.S. by recommending another safe and effective COVID-19 vaccine,” said Walensky. “If you have been waiting for a COVID-19 vaccine built on a different technology than those previously available, now is the time to join the millions of Americans who have been vaccinated. With COVID-19 cases on the rise again across parts of the country, vaccination is critical to help protect against the complications of severe COVID-19 disease.”
Walensky’s action made Novavax the fourth vaccine to be authorized in the United States for the prevention of COVID-19, joining those manufactured by Pfizer/BioNTech, Moderna and Janssen/Johnson & Johnson.
Walensky and the ACIP acted less than a week after the FDA issued an emergency use authorization for Novavax.
The AAFP has approved the advisory committee’s recommendations after conducting an expedited review of the evidence and has updated its main COVID-19 and COVID-19 Vaccine webpages with this latest information.
“This vaccine is a welcome addition to our toolbox, but it’s important to remember that the COVID pandemic is not over,” cautioned Pamela Rockwell, D.O., of Ann Arbor, Mich., the Academy’s liaison to the ACIP. “COVID-19 continues to cause new cases, hospitalizations and deaths in the United States and also contributes to health inequities by disproportionately affecting American Indian/Alaska Native, Black and Hispanic/Latino people.
“Family physicians and other primary care clinicians are the most trusted source of vaccine information and guidance for most patients,” she added. “I strongly urge anyone not yet vaccinated to consider vaccination now as cases start to rise across the country once again.”
Novavax first received approval for use in adults from the European Medicines Agency in December 2021, followed by the United Kingdom’s Medicines and Healthcare products Regulatory Agency in February 2022.
The vaccine is administered as a two-dose primary series, with the second dose given three to eight weeks after the first. It has not been authorized for use as a booster in conjunction with other types of COVID-19 vaccines.
Unlike the vaccines developed by Pfizer-BioNTech and Moderna, which involve the use of mRNA, Novavax is a traditional protein-based vaccine that contains the spike protein from SARS-CoV-2, the virus that causes COVID-19 disease, along with an adjuvant called Matrix-M to stimulate a response in the immune system. The spike protein is produced in insect cells, while the adjuvant contains saponin extracts from the bark of the Chilean soapbark tree.
According to the CDC, protein-based vaccines have been used in the United States for more than 30 years to prevent infectious diseases such as hepatitis B, influenza and pertussis.
On July 11, the Biden administration announced that it had secured 3.2 million doses of Novavax, making the vaccine available for free to states, jurisdictions, federal pharmacy partners and federally qualified health centers.
Although Novavax has some advantages over mRNA vaccines, the vaccine is not without its drawbacks. Whereas mRNA vaccines require extremely cold temperatures for adequate storage, Novavax may safely be stored in a refrigerator; furthermore, the vaccine does not have to be diluted before administration, which increases its ease of use. However, the vaccine is marketed in vials that contain 10 0.5 mL doses, and the vial must be discarded six hours after the first dose is withdrawn, which creates the potential for wasted doses.
As for adverse effects, “There are no concerning serious side effects noted with this new vaccine to date,” Rockwell told AAFP News. “The benefits of COVID-19 vaccination clearly outweigh the risks of contracting COVID-19 disease.”
An FDA fact sheet for vaccine recipients and caregivers notes that although some individuals who have received Novavax experienced myocarditis or pericarditis, the risk is very low, with symptoms occurring within 10 days after vaccination in most cases. According to Rockwell, results from multiple studies indicate that the risk of myocarditis associated with COVID-19 disease is much greater than the risk associated with vaccination, and that it is often more serious in those who contract the disease.
The FDA also has published a fact sheet for health care professionals who administer the vaccine that contains additional information, including storage and dose preparation specifics.
Whether approval of the Novavax vaccine leads to an increase in the percentage of adults vaccinated against COVID-19 will not be known for some time. According to the latest CDC data, as of July 13, just under 90% of all U.S. adults had received at least one dose of a COVID-19 vaccine, and 77% are considered fully vaccinated. A Kaiser Family Foundation issue brief, meanwhile, stated that COVID-19 vaccination coverage and booster intake has plateaued and remains uneven throughout much of the country.
“There are between 26 million and 37 million adults in the U.S. who still have not received a dose of a COVID-19 vaccine,” said Rockwell. “It is my hope that some of these unvaccinated people will consider the Novavax COVID-19 vaccine at this time if the reason for their vaccine hesitancy is due to concern over mRNA vaccine technology. There is nothing ‘new’ about how this vaccine was made, and most people have some trust in the safety of tried-and-true flu vaccines that are made in the same way as Novavax.”
There is also some uncertainty regarding the Novavax vaccine’s effectiveness against SARS-CoV-2 subvariants — in particular, the BA.5 omicron subvariant, which has become the dominant strain of COVID-19 in the United States and is responsible for roughly two-thirds of infections in the country. Despite the uncertainty, Rockwell is optimistic the vaccine will provide some measure of protection, particularly in individuals who have not previously been vaccinated.
“There is no way to know for sure how much protection Novavax will offer against some of the new COVID-19 subvariants, as the company’s phase 3 clinical trial was conducted prior to the circulation of delta and omicron,” Rockwell said. “However, given that Novavax demonstrated comparable efficacy against serious illness and death due to COVID-19 during that trial as compared with the efficacy of the mRNA vaccines in similar trials, it is thought that Novavax will offer the same benefits seen today against newer COVID-19 variants as seen with the mRNA vaccines.”
The ACIP will hold its next scheduled meeting Oct. 19-20 but may hold additional meetings before then to discuss other COVID-19 vaccines if the need arises.
Be sure to bookmark the Academy’s COVID-19 webpage for the latest information.