Emergency Use Authorization (EUA)

An Emergency Use Authorization (EUA) is a regulatory mechanism that allows the FDA to facilitate the availability and use of medical countermeasures, including vaccines, during public health emergencies. EUAs have been used for anthrax, Ebola, H1N1 influenza, and most prominently, COVID-19.

Legal Authority

EUAs are authorized under Section 564 of the Federal Food, Drug, and Cosmetic Act, as amended by the Project BioShield Act of 2004 and the Pandemic and All-Hazards Preparedness Reauthorization Act.

Criteria for EUA Issuance

The FDA may issue an EUA when all four criteria are met:

1. Public health emergency: A public health emergency has been declared
2. No adequate alternatives: No sufficient, approved alternatives exist
3. May be effective: The product "may be effective" based on available evidence
4. Known vs. unknown risks: Known and potential benefits outweigh known and potential risks

EUA vs. Full Approval

Post-EUA Monitoring

Products authorized under EUA are subject to enhanced safety monitoring:

• Manufacturers must report adverse events to VAERS
• FDA conducts active surveillance through BEST system
• Additional studies may be required
• CDC and FDA publicly report safety data

EUA to Licensure Pathway

Products granted EUA may subsequently receive full approval:

• Manufacturer submits BLA with complete clinical trial data
• FDA conducts full review of manufacturing and quality
• VRBPAC may vote on licensure
• Full approval replaces EUA authorization

Sources & Citations

• FDA: EUA Vaccines Explained
• FDA: EUA Guidance