FDA Approval & Emergency Use Authorization (EUA)

What is Emergency Use Authorization (EUA)? 

Emergency Use Authorization (EUA) is a tool used to strengthen the nations response to biological, radiological, and nuclear (CBRN) threats, including infectious diseases.  After the 9/11 attacks, and the later anthrax mailings, Congress enacted the Project Bioshield Act of 2004, which gave the FDA the ability to authorize medical devices and drugs during a declared emergency [1].  Emergency Use Authorization is still an evidence-driven process and requires: 1) proof of effectiveness; 2) a risk-benefit analysis; and 3) no approved alternatives [2].  After an EUA has been issued, the FDA does extensive monitoring for safety and efficacy and can retract authorizations at any time. 

What is required for full FDA approval?

FDA approval requires intensive quality and safety measurements. This is done through multiple clinical trials, which contain tens of thousands of participants, and an in-depth review of efficacy and manufacturing data and well as 6-months of follow-up safety data after clinical trials end.  In certain circumstances, this process can be accelerated by giving it various designations like: fast track, breakthrough therapy, accelerated approval, and priority review [3].  There are no shortcuts in the science required to prove that something like the COVID-19 vaccine is safe and effective. Instead, the red tape and competition of a normal FDA approval is pulled back to provide a fast pass for vaccines and other therapies during a global emergency.

The typical process for vaccine development and approval can take anywhere from 5 to 10 years, so how can the COVID-19 vaccine be created so fast and still be considered safe?

COVID-19 vaccines are 30+ years in the making.  After the SARS outbreak in 2003, coronaviruses were a primary target for mRNA technology already being developed [4].  Additionally, a partnership between the Departments of Health and Human Services (HHS) and Defense (DOD) known as Operation Warp Speed (OWP) provided investment and coordination for the purpose of development, manufacturing, and distribution of COVID-19 testing, treatments, and vaccines. It accelerated FDA approval since it allowed for clinical trials to overlap and promising vaccine candidates to start manufacturing early [5].

Have there been any other uses for EUA outside of COVID-19 vaccination?

Yes. Over 400 EUAs have been issued including COVID-19 treatments like convalescent plasma, Remdesivir, and various medical devices.  Hydroxychloroquine also received an EUA initially, but posed more risk than benefit and was retracted.  EUAs have also been issued for other infectious diseases like anthrax, ebola, enterovirus, H7N9 influenza, and Middle East respiratory syndrome [6,7].

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  1. Institute of Medicine. Forum on Medical and Public Health Preparedness for Catastrophic Events. Medical Countermeasures Dispensing: Emergency Use Authorization and the Postal Model, Workshop Summary. Washington (DC): National Academies Press (US); 2010.  
  2. U.S Food and Drug Administration. Emergency Use Authorization of Medical Products and Related Authorities. January 27, 2018.  
  3. U.S Food and Drug Administration. Development & Approval Process: Drugs. Oct 28, 2019.  
  4. Ball, P. The lightning-fast quest for COVID vaccines — and what it means for other diseases. Nature. December 18, 2020. 
  5. National Institute of Allergy and Infectious Disease. COVID-19 Clinical Research. November 2, 2020. 
  6. U.S Food and Drug Administration. Emergency Use Authorization. August 30, 2021. 
  7. Johns Hopkins. Emergency Use Authorization. October 20, 2020.