4 COVID-19 vaccines have reached final stage of testing in United States
Four coronavirus (COVID-19) vaccines have reached the final stage of testing, and one of the frontrunners is making progress toward the goal of proving to be safe and effective. Last week, Pfizer received permission from the Food and Drug Administration to enroll volunteers as young as 12 years old. Some trial participants receive the actual vaccine, while the rest receive a placebo. Neither the researchers nor the participants know which group has received the vaccine or the placebo. Ultimately, theyโll compare the groups to see if fewer of the participants who received the actual vaccine got infected.