EUA and full approval share similar first steps
For emergency clearance and full approval of COVID-19 vaccines, the FDA first requires initial safety studies on a small number of people. Here, researchers are documenting potential adverse events, or side effects, that the vaccine can cause. Researchers are also determining the safest and most effective dose of the vaccine.
Once the vaccine is determined to be safe and an optimal dose is identified, researchers will create larger studies to verify its effectiveness in a controlled environment where some people receive the vaccine while others receive a placebo.
It is important to note that the number of people who participated in the first COVID-19 safety studies was similar to the safety studies of other commonly used vaccines, including vaccines against tetanus, diphtheria, pertussis and meningitis. More than 43,000 adults participated in the early phases of the Pfizer BioNTech clinical trial, more than 30,400 in Moderna and more than 44,000 in Johnson and Johnson. Half of the participants in each study received a vaccine, while the other half received a placebo.
Where EUA and full approval differ
From that point on, emergency use clearance and full FDA approval for COVID-19 vaccines follow different clinical study requirements.
For emergency use authorization, the FDA requires that at least half of the participants in the original studies be followed for at least two months after vaccination. Indeed, the vast majority of vaccine-related side effects occur immediately after vaccination.
Full FDA approval, on the other hand, requires that participants in the original studies be followed for at least six months. Reviewers look at data from the same study participants, but collected over a longer period of time. All adverse events are reviewed. The manufacturer must also provide more detailed manufacturing plans and processes, as well as a higher level of monitoring and inspections. All of this adds a lot more time to the review process.
Pfizer and Moderna have both started their ongoing submission for approval under the FDA’s “Fast Track” process, designed to expedite review. This allows companies to submit parts of their approval request to the FDA for review as they are completed.
Full FDA approval will likely initially only apply to the same age groups that were tested in the original emergency use authorization. This means that the vaccine will likely be approved first for people aged 16 and over for Pfizer and 18 and over for Moderna. Ongoing submission will allow vaccine approval for younger groups as more data becomes available.
Different deadlines, the same rigorous requirements
Full FDA approval is an important step that can help build confidence among hesitant vaccines about vaccine safety. But the real test of the vaccine came when it was first granted emergency use authorization. Next, researchers identified the majority of its potential side effects and proved its ability to protect against serious illness.
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This article is republished from The Conversation, a nonprofit news site dedicated to sharing ideas from academic experts. It was written by: Jennifer Girotto, University of Connecticut.
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Jennifer Girotto does not work, consult, own stock or receive funding from any company or organization that would benefit from this article, and has not disclosed any relevant affiliation beyond her academic position.