Emergency Use Authorisation (EUA)
A mechanism allowing regulatory authorities to authorise unapproved medical products during public health emergencies based on a lower evidence threshold than full approval. EUAs are temporary and must be reassessed as more data become available.
Technical Context
EUA authority (Section 564 of FD&C Act) requires: declared emergency by HHS Secretary, evidence the product may be effective (lower bar than 'substantial evidence of effectiveness' for full approval), known/potential benefits outweigh known/potential risks, and no adequate approved alternatives. EUA conditions include: distribution restrictions, informed consent requirements (must inform recipients of EUA status, known/potential risks and benefits, and right to refuse), reporting requirements, and specific use limitations. EUAs are temporary — they must be reassessed when the emergency declaration ends and can be revoked if conditions are no longer met. The transition from EUA to full BLA/NDA approval requires submission of a complete application with more comprehensive data. EUA was rarely used before the COVID-19 pandemic but has become a well-known regulatory pathway.