The Pfizer COVID-19 vaccine trial includes about 44,000 people, but the unique thing about this round is half of participants have very diverse backgrounds.

It also includes teens as young as 16, and people with compromised immune systems.

WATCH: Pfizer says early data signals COVID-19 vaccine is 90% effective at preventing the virus

The company is reporting an efficacy rate above 90%, seven days after the second dose was administered. Even back in August, Pfizer described the vaccine as “well tolerated” with fewer than 20% of participants seeing mild to moderate symptoms.

News 12's Beth Cefalu spoke a phase 3 participant this fall, because it's a blind study News 12 doesn’t know if he received the vaccine or placebo, but he told Cefalu he had no symptoms or issues from the trial and was happy to participate.

"If you want to do something for humanity this is the time and period in history we have to do something," says Robert Perez.

The company hopes to submit the vaccine for regulatory approval later this month with a goal to distribute 100 million doses worldwide by the end of this year.