Under section 564 of the Federal Food, Drug, and Cosmetic Act (FD&C Act), the FDA Commissioner may allow unapproved medical products or unapproved uses of approved medical products to be used in an emergency to diagnose, treat, or prevent serious or life-threatening diseases or conditions caused by chemical, biological, radiological or nuclear threat agents when there are no adequate, approved, and available alternatives. Vaccines that receive an EUA may later be fully licensed by the FDA.
Last reviewed:
November 16, 2024
Both the Pfizer-BioNTech COVID-19 Vaccine and the Moderna COVID-19 Vaccine are lipid nanoparticle-formulated, nucleoside-modified mRNA vaccines encoding the prefusion spike glycoprotein of SARS-CoV-2, the virus that causes COVID-19. The 2024–2025 formula targets the Omicron variant KP.2 sublineage of the spike protein. Visit this CDC website for more details about how mRNA vaccines work: www.cdc.gov/covid/vaccines/how-they-work.html.
Last reviewed:
November 16, 2024
The original COVID-19 vaccines all targeted the spike protein of the original SARS-CoV-2 virus. The 2024–2025 formulation vaccines target the spike proteins of more recently circulating strains, known as the Omicron KP.2 (mRNA vaccines) or JN.1 (protein vaccine) strains. The update is intended to boost production of antibodies that protect more effectively against disease caused by currently circulating Omicron subvariants.
The process of updating the strain without changing anything else is similar to the seasonal strain changes made for influenza vaccinations each year; FDA does not require manufacturers to repeat the large-scale clinical trials necessary for the original products before authorizing updated vaccines. Vaccine safety, side effects, and risk of allergic reactions are expected to be comparable to earlier formulations of vaccines of the same brand and dose. As with seasonal influenza vaccines, future COVID-19 vaccines can continue to be updated when needed, as the circulating viruses evolve.
Last reviewed:
November 16, 2024
No. The last U.S. doses of Janssen COVID-19 Vaccine expired May 7, 2023.
Last reviewed:
November 16, 2024
Novavax COVID-19 Vaccine, Adjuvanted contains the Omicron JN.1 subvariant SARS-CoV-2 spike protein and Matrix-M adjuvant. The saponin-based adjuvant is made from extracts of the bark of the Soapbark tree native to Chile. It is added to enhance the immune response of the vaccine recipient. The spike protein is produced in insect cells.
It is authorized for emergency use in people age 12 years or older as a two-dose primary series for previously unvaccinated individuals (whether or not they are immunocompromised), with the doses given at least 3 to 8 weeks apart. Previously unvaccinated people age 65 years and older and previously unvaccinated people age 12 years and older who have moderate or severe immunocompromise should receive an additional dose 6 months after dose 2 (minimum interval 2 months). People with moderate or severe immunocompromise may receive additional doses of COVID-19 vaccine (minimum interval 2 months) as determined by their healthcare team, their personal preference, and specific circumstances.
Individuals age 12 years through 64 years who have had one or more doses of any previous authorized or approved COVID-19 vaccine formulation are recommended to receive only one dose of the current 2024–2025 Novavax formulation. People age 65 years and older and people age 12 years and older with moderate or severe immunocompromise who have received one or more doses of a previous season’s COVID-19 vaccine and receive a dose of the 2024–2025 Formula Novavax vaccine should receive an additional dose of any 2024–2025 COVID-19 vaccine 6 months (minimum interval 2 months) following the first dose. Those with moderate or severe immunocompromise may receive additional doses as determined by their healthcare team, their personal preference, and specific circumstances.
Last reviewed:
November 16, 2024
The effectiveness of Novavax COVID-19 Vaccine against currently circulating variants of SARS-CoV-2 is not precisely known. Clinical trials of this vaccine were conducted against earlier variants no longer in circulation; however, the vaccine showed very good effectiveness against moderate to severe disease during clinical trials. Testing conducted on antibodies in the serum of Novavax vaccine recipients suggests that vaccination provides substantial protection against severe disease and death caused by currently circulating variants, consistent with other available COVID-19 vaccines.
Last reviewed:
November 16, 2024
