After receiving the first dose of the Moderna COVID-19 vaccine in New York City yesterday evening I became curious about why and how Emergency Use Authorizations (EUAs) are issued for products (such as the COVID-19 vaccines) that are not yet approved by the Food & Drug Administration (FDA). The two main pages where I found information are the website for the Centers for Disease Control and Prevention (CDC) and the Federal Register: the Daily Journal of the United States Government. While the CDC link gives a lot of information about protecting oneself and others from the virus with links to other trustworthy sources as necessary, the Federal Register link contains the specific EUA notices for both the Pfizer and Moderna vaccines. Reading these sites satisfied any lingering concerns I may have had about the vaccines, so I encourage others to read them too. I’ll briefly summarize what I learned.
COVID-19 is dangerous enough that after thorough testing–I’ll discuss the Moderna testing in a minute–the FDA issued EUAs for both vaccines while they continue to be studied for full authorization. Let’s face it: this virus has killed half a million people in the United States alone in only one year. The full vaccine product approval process is lengthy, and with a virus this lethal it is reasonable to assume hundreds of thousands or even millions more people could die, if the vaccines are put through the entire approval process before being authorized for use. So after reviewing the scientific data from the ongoing Phase 1/2/3 trials for those two vaccines, the FDA issues EUAs for them.
These vaccines and others are currently going through the full approval process. EUAs were issued for these two, because based on their safety so far, their effectiveness so far, and the seriousness of the virus the FDA has concluded the vaccines may be effective. The vaccine manufacturers are continuing the trials and reporting the results as is required by the approval process. If data comes back that shows the vaccines are not safe or effective, their EUAs would be revoked. (This is what happened when hydroxychloroquine sulfate (HCQ) and chloroquine phosphate (CQ) were found to not be effective or safe for treating COVID-19.)
Since Moderna is the vaccine I received, I’ll talk about its testing as recorded in The Federal Register. As of 18 December 2020 when the EUA was issued, it is in Phase 3 of trials. Safety data was reviewed for 30,351 participants over the age of 18. Those participants were followed for 7 weeks after they received the second dose of the vaccine, and there were no specific safety concerns that would make it ineligible for an EUA. Even after following up an average of 9 weeks after receiving the vaccine the FDA didn’t find any evidence that would make it necessary to change their assessment. Therefore, it is reasonable to assume the vaccine is safe.
Nine weeks after 28,207 participants over age 18 received the second dose of the vaccine the FDA studied the data and found the vaccine is 94.1% effective in preventing the virus at least two weeks after the second dose. At seven weeks the data had shown the vaccine was 94.5% effective, so the results at nine weeks were consistent with that earlier data. Based on that data, it is reasonable to assume the vaccine is effective. ScienceNews reports the FDA has recommended COVID-19 vaccines be at least 50% effective, and the World Health Organization (WHO) prefers efficacy be at least 70%. This vaccine far surpasses both recommendations.
Even without knowing these details I was comfortable with receiving the vaccine last night. I hadn’t heard any reliable scientific or media sources raise an alarm about the vaccine’s safety, and enough people had received it before I was eligible for me to reasonably assume it was safe for me to get it. My reading today further convinced me the organizations responsible for monitoring our health and safety are doing what they can to make sure the vaccines and any treatments are safe before administering them, and if by some chance they are later found to not be safe, their use is prohibited. This virus is new, and scientists are quickly learning as they go and even changing their recommendations as they learn new things. I am both impressed and grateful.