Some of the participants are from right here in Houston. Dr. Hana El Sahly is at the forefront of the trial on a national level and at the Baylor College of Medicine.
RELATED: First COVID-19 vaccine tested in US poised for final testing
[Ads /]
"The whole point of these trials is to determine the efficacy and the safety of the vaccine. Meaning if the vaccine, when we compare it to (the) placebo, results in the lower incidents of COVID compared to the general public," said Sahly.
Moderna said it's getting a good pool so far.
"Generally speaking, the interest in participating in COVID trials has been robust, and I project clinical trials will not have problems," said Sahly.
Volunteers will be given a placebo or a vaccine, but they won't be made aware of which one they were given until the end of the study. Officials said along the way, they will still be able to gather data from the participants and determine if the vaccine is working.
SEE MORE: What you need to know about possible COVID vaccine
[Ads /]
"Regardless, they are monitoring bodies that are evaluating the data, so we have an earlier reading on the vaccine efficacy," said Sahly.
The idea is to have a large pool of participants because officials can gather data quicker that way.
"Given the urgency and the public health need as a result of this pandemic, all phase three efficacy trials are being designed with a large sample size," Sahly added.
RELATED: Houston man details his experience with COVID-19 vaccine trial
Follow Marla Carter on Facebook, Twitter and Instagram.