About COVID-19 Vaccines
Vaccine Safety Vaccine Facts Resources

Updated Jan. 8, 2022


The Pfizer-BioNTech, Moderna, and Johnson & Johnson Janssen Biotech COVID-19 vaccines have all undergone Phase III clinical trials conducted worldwide with almost 120,000 volunteers and have received emergency use authorizations (EUA) from the Food and Drug Administration (FDA) for use in the prevention of COVID-19 in the United States.

The Pfizer-BioNTech COVID-19 vaccine received full FDA approval for use in individuals 16 years and older for the prevention of COVID-19. It is the first COVID-19 vaccine to receive full approval. FDA approval was followed by an independent review by the CDC Advisory Committee on Immunization Practices (ACIP), which provided its recommendation for use of the vaccine. The vaccine is marketed as Comirnaty (koe-mir’-na-tee). The vaccine is also available for use in individuals ages 5-15 under its previous EUA.

NOTE: CDC recommends that people who are starting their vaccine series or getting a booster dose get either Pfizer-BioNTech or Moderna (mRNA COVID-19 vaccines). The mRNA vaccines are preferred over Johnson & Johnson’s Janssen COVID-19 vaccine in most circumstances. Learn more

Data Collection and Review

Vaccine makers are required to track any adverse reactions that vaccine clinical trial participants have. To do this for the COVID-19 vaccines, they collected data on thousands of participants for at least one month after both doses to ensure that they hadn’t had any unexpected reactions to the vaccine. The FDA next reviewed all data from the clinical trials before granting EUA for each vaccine.

Once EUA was granted, the federal Advisory Committee on Immunization Practices (ACIP) met to review the vaccines and determine whether or not they could safely recommend the vaccines and for which populations. Once ACIP recommended each COVID-19 vaccine (and later, boosters for each vaccine), they were next reviewed by the Western States Scientific Safety Review Workgroup, which reviews the vaccines to ensure their safety before they are used in Washington, Oregon, Nevada, Colorado and California. The Scientific Safety Review Workgroup includes Washington, Oregon, Nevada, Colorado and California; panel members include nationally recognized experts appointed by each of the member states. Learn more

For more information, see our Vaccine FAQ and Vaccine Development. Other information provided on the Resources tab above.

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