With talk of the possible availability of a vaccine candidate heating up, you might have heard the term Emergency Use Authorization — or EUA — all over the news lately. But what is it exactly, and how does it apply to vaccines?
Emergency use authorization is what its name suggests: a medical product that gets special authorization by the US Food and Drug Administration to be used during an emergency. Sometimes it’s a product that has already been FDA-approved, but for another condition, and sometimes it’s a new product that hasn’t yet received the agency’s green light.
There is a lot of ongoing concern and debate about whether any vaccine candidate should be granted an EUA — or outright approval — without first completing Phase 3 clinical trials.
The 411 of EUAs
According to the FDA’s website, during public health emergencies, the agency can use Emergency Use Authorizations “to help make medical products available as quickly as possible by allowing unapproved medical products to reach patients in need when there are no adequate, FDA-approved and available alternatives.”
But that’s only if “the known and potential benefits of the product, when used to diagnose, prevent, or treat the identified disease or condition, outweigh the known and potential risks of the product.”
So, in essence, what an EUA does is speed up the process of getting potentially helpful medical products authorized for a specific use to the public during a health emergency, without the rigorous testing and subsequent scrutiny that’s usually required to get FDA approval — which traditionally takes years.
When the health emergency is over, “then any EUA(s) issued based on that declaration will no longer remain in effect,” according to the FDA. But the manufacturer can still submit documentation to the agency for regular approval.
The EUA hasn’t been around that long. The process was included within the Project Bioshield Act passed by Congress in 2004, which enabled the federal government to prepare and stockpile new “medical countermeasures” during a declared public health emergency.
And despite issuing many EUAs over the years, only one vaccine has ever received one – but it was in an unusual and controversial circumstance. In 1997, the Department of Defense began a mandatory anthrax vaccination program. Shortly thereafter, soldiers claimed the vaccine made them sick, so they sued and a judge put a hold on the program in 2003. The Department of Defense asked for an EUA that then overrode the court ruling in 2005, so it could continue vaccinating military personnel — this time on a voluntary basis.
EUAs during this pandemic
During the Covid-19 pandemic, the FDA has granted EUAs many times to a wide range of medical products, such as ventilators; personal protective equipment, including masks; molecular and antigen tests to diagnose Covid-19, and serologic tests to look for antibodies; and even treatments, such as remdesivir and convalescent plasma.
An EUA can be revoked,as in the case of hydroxychloroquine and chloroquine. These drugs had already been approved to treat and prevent malaria, and showed promise against the novel coronavirus in laboratory studies. Small early trials in Covid-19 patients added to the optimism, and the medication was touted by President Trump. But larger studies found the medications to be ineffective in treating patients with Covid-19. Additionally, one of the side effects could also potentially be dangerous in people who had pre-existing heart conditions.
After about two and a half months with EUA, the emergency authorization was revoked.
Many experts see granting an EUA to a vaccine against Covid-19 as problematic. For one, vaccines are given to healthy people by choice, unlike medications that are given to gravely ill patients who might die without them. So drugmakers have a higher bar, so to speak, to make sure there are no unexpected side effects that make healthy people sick — and the only way to find out is in large-scale trials, like those going on right now.
The FDA has said it would hold a vaccine to a higher standard. Dr. Peter Marks, who heads FDA’s Center for Biologics Evaluation and Research, said Thursday that requirements will be stricter than for an emergency use authorization for an experimental drug.
“For us, for a vaccine for which there is adequate manufacturing information, if we going to do an emergency use authorization, it is going to really be like an emergency use authorization plus,” Marks told a seminar hosted by Duke University’s Margolis Center for Health Policy.
