The US Food and Drug Administration (FDA) has approved Novavax’s Covid-19 vaccine, Nuvaxovid, but with restrictions. The approval, detailed in a letter from the agency, limits the vaccine's use to individuals 65 and older and those aged 12 and up who have at least one underlying condition that increases their risk of severe illness from COVID-19. Pediatric studies for children under 12 are still pending.

Novavax President and CEO John Jacobs stated that market research and US Centers for Disease Control and Prevention (CDC) statistics indicate that older individuals and those with underlying conditions are the populations most likely to seek out COVID-19 vaccination seasonally. He hailed the approval as a significant milestone, demonstrating the company's commitment to these populations and providing a protein-based vaccine option.

The CDC lists various conditions that may increase the risk of severe illness from Covid-19, including older age, asthma, diabetes, lung disease, obesity, and pregnancy.

The Novavax Covid-19 vaccine, utilizing traditional protein-based technology, had been under emergency use authorization since 2022. In contrast, Pfizer/BioNTech and Moderna employ mRNA technology. While Pfizer and Moderna's vaccines are FDA-approved for those 12 and up and remain available under emergency use authorization for children as young as 6 months, Novavax faced delays in securing full approval.

The FDA had initially aimed to approve the Novavax vaccine by April 1, but the decision was delayed while the agency sought additional data. The approval letter issued on Friday mandates Novavax to conduct postmarketing studies to assess the risk of myocarditis and pericarditis – inflammation of the heart muscle and surrounding membrane – in vaccine recipients.

Although these conditions have been rarely reported after Covid-19 vaccination, some cases were observed in Novavax vaccine trials, suggesting a potential increased risk. However, both the CDC and its Advisory Committee on Immunization Practices maintain that the benefits of Covid-19 vaccination outweigh the rare risk of heart inflammation across all recommended groups.

The CDC’s vaccine advisors are considering revisions to the agency’s guidance for annual Covid-19 shots, potentially focusing on older adults, those with weakened immune systems, and individuals more likely to be exposed to the coronavirus.

U.S. Health and Human Services Secretary Robert F. Kennedy Jr. has made misleading statements about the safety of vaccines. HHS did not respond to a request for comment on the Novavax approval.

Novavax, whose protein-based shot uses an older technology, missed out on the pandemic vaccine windfall - enjoyed by rivals Moderna and Pfizer which make messenger RNA-based vaccines - due to manufacturing issues and regulatory hurdles.