COVID-19 vaccine testing included people with underlying health conditions

A common critique of the COVID-19 vaccines is that they were developed and distributed with unprecedented speed, without being tested extensively enough.

"The COVID-19 investigational vaccines were released to the public after only two months of testing in healthy humans," claims a man appearing in a Facebook video labeled, "Why I am not getting THE SHOTS."

The post was flagged as part of Facebook’s efforts to combat false news and misinformation on its News Feed. (Read more about our partnership with Facebook.)

The broader arguments of the video are that pharmaceuticals such as vaccines cannot be trusted without studies of their long-term effects, and that the risks of COVID-19 are better known than the potential risks of vaccines. 

For this fact-check, we looked at the claim that the vaccines were tested on "healthy people," which suggests that the results of the clinical trials were skewed to exclude those who had health problems that predisposed them to contracting COVID-19 or having bad side effects from the vaccine. 

The United States allowed three different COVID-19 vaccines — Moderna and Pfizer-BioNTech, both in December 2020, and Johnson & Johnson, in February 2021. All three were authorized for emergency use based on data submitted around two to three months into their clinical trials.

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But the claim about testing in "healthy humans" is misleading. All three drug makers’ trials included people with underlying health conditions that increase the risk of severe COVID-19.  

Moderna’s study involved 30,420 volunteers ages 18 and over in the United States. Nearly 17% were people under 65 who had medical conditions that predisposed them to severe COVID-19. 

Pfizer’s study included 43,548 people ages 16 and up in the United States and five other countries. Overall, 70% were obese or overweight (as measured by body mass index), and 21% had at least one coexisting condition such as diabetes or chronic pulmonary disease.

Johnson & Johnson’s vaccine was tested on 43,783 adults in the United States and several other countries. Among them, 41% had health conditions that increased their risks for severe COVID-19, including obesity, high blood pressure, Type 2 diabetes or HIV.

People who participated in clinical trials of the vaccines continue to be monitored, and the federal Centers for Disease Control and Prevention monitors the administration of vaccines to the general public for possible side effects that are severe or unexpected.

Public health officials, scientists and doctors say the vaccines are safe and protective during pregnancy, based on trials, studies and the available safety data. The CDC on Aug. 11 recommended vaccination for those who are pregnant or looking to get pregnant, as the safety evidence becomes more conclusive and new infections from the delta variant continue to mount.

The statement contains only an element of truth. We rate it Mostly False.