COVID-19 Vaccine Authorization vs. Approval What's the Difference?

Authorization vs approval

Pfizer and Moderna recently asked the Food and Drug Administration for formal approval of their COVID-19 vaccines, which have already been given to millions of Americans. That raises the question: Aren’t the vaccines already approved?

The answer is yes. And no.  

Both drug makers got the green light from the FDA to use the vaccines in the fight against the pandemic, but that permission came under something called an Emergency Use Authorization. FDA Approval is different. Here’s an explanation of the two terms.

Emergency Use Authorization (EUA)

During an emergency such as the COVID-19 pandemic, the FDA can quickly make a drug, vaccine, test or medical product available when there are no other adequate options already approved and available. The process is speedier than formal approval because it relies on the “best available evidence,” rather than waiting for comprehensive analysis of all data, which may take years. 

In the case of Pfizer and Moderna, both manufacturers submitted EUA applications late last year. This included data from rigorous testing, such as information on side effects, risks, and effectiveness. The applications reported results from:

  • Phase 1 clinical trials in which the vaccines were given to a small number of generally healthy people
  • Phase 2 trials, which were expanded to include more people, with differing health statuses, from different demographic groups, and testing various dosages
  • Phase 3 trials (interim results). These trials looked at a much broader group of people and studied immune response after vaccination, compared to a placebo. These trials will continue for many months. 

The applications were reviewed by a data safety monitoring board made up of independent scientific and public health experts, who then recommended the vaccines for EUA. The FDA looked at those recommendations and all the available data, while carefully balancing the potential risks and benefits, before authorizing the vaccines for emergency use among adults last December. Pfizer was granted EUA for youths aged 12-16 in May.

Those authorizations have paid off. The Centers for Disease Control has concluded that the Pfizer and Moderna vaccines are incredibly effective and safe. As a result, communities with higher vaccination rates are seeing declining numbers, while those with lower rates are seeing increases. 

FDA Approval

Both Pfizer and Moderna have asked the FDA for full approval of their vaccines. Approval wouldn’t change much from the public’s perspective. FDA approval would allow the drugmakers to market their vaccines directly to the public and could give Americans more confidence in the safety and effectiveness of the vaccines, but nothing would change with the vaccines themselves. As part of their applications, Pfizer and Moderna are providing several months of additional data from Phase 3 clinical trials, and will continue to provide updated data in the future.

Should I wait for FDA approval?

Full approval could be months away, but the virus is here now, infecting more Americans every day. Experts say there’s no need to wait, and every reason to get vaccinated today.

Since March 23, when all Utahns 16 and older became eligible to receive the vaccine:

  • There have been 27,017 total COVID-19 cases Utah – 97% have been unvaccinated people.
  • There have been 1,532 people hospitalized – 95% of them were unvaccinated.
  • There have been 110 deaths – 98% of them were unvaccinated.


“These vaccines have been a game changer,” said Tamara Sheffield, MD, Intermountain Healthcare’s Medical Director for Community Health and Prevention. “All you need to do is look at our ICUs, which have fewer and fewer COVID patients. And almost all those we do see have one thing in common: They haven’t been vaccinated yet. 

“Don’t wait to get vaccinated. It could save your life or the life of someone you love.”