EUA

Emergency Use Authorization (EUA) is a mechanism established under Section 564 of the Federal Food, Drug, and Cosmetic Act that allows the FDA to facilitate the availability and use of medical countermeasures during public health emergencies.

When EUA can be issued:
- Emergency declaration by HHS Secretary
- No adequate alternatives exist
- Known and potential benefits outweigh known and potential risks
- Evidence of effectiveness (lower standard than full approval)

EUA vs. traditional pathways:
- 510(k): Requires substantial equivalence to predicate device
- PMA: Requires extensive clinical data proving safety and effectiveness
- EUA: Requires evidence that benefits may outweigh risks during emergency

COVID-19 EUA experience:
The pandemic demonstrated EUA's importance:
- Diagnostics: Over 400 COVID-19 tests authorized
- Therapeutics: Remdesivir, monoclonal antibodies, antivirals
- Vaccines: Pfizer, Moderna, J&J vaccines (later transitioned to BLA approval)
- Medical devices: Ventilators, PPE, pulse oximeters

EUA requirements for medical devices:
1. Letter of authorization request to FDA
2. Evidence supporting safety and effectiveness
3. Manufacturing information and facilities
4. Proposed labeling and fact sheets
5. Risk-benefit analysis

Post-EUA requirements:
- Periodic reporting on safety and performance
- Compliance with conditions of authorization
- Notification of changes to device or manufacturing
- Post-market surveillance activities

Transition from EUA to regular approval:
Manufacturers typically pursue:
- 510(k) clearance for lower-risk devices
- De Novo classification for novel low-moderate risk devices
- PMA approval for high-risk devices

EUA termination:
- Emergency declaration ends
- FDA revokes based on new evidence
- Manufacturer withdraws authorization
- Regular approval obtained (transition period allowed)

Key limitation: EUA products must include statement "This product has not been approved or cleared by FDA" and can only be used during the declared emergency unless transitioned to regular approval.