Pfizer finishes final COVID-19 vaccine trial, says it's proven 95% effective

Nov. 18 (UPI) -- Pfizer and BioNTech announced Wednesday that their COVID-19 vaccine candidate has completed a final-stage clinical trial and was found to be 95% effective, and they'll seek U.S. approvals in the coming days.

The companies said the results of the finished final large-scale study of their BNT162b2 vaccine candidate found it has an efficacy rate of 95% in human volunteers who had both prior and no prior coronavirus infection.

The results were based on 170 cases of COVID-19, of which 162 were observed in a group administered a placebo against just eight cases in trial volunteers given the BNT162b2 vaccine.

Pfizer and BioNTech said they will submit an emergency authorization request to the Food and Drug Administration "within days" based on the results, which improve on a on 90% efficacy finding last week that was based on early data of the final-stage trial.

"The study results mark an important step in this historic eight-month journey to bring forward a vaccine capable of helping to end this devastating pandemic," Pfizer Chairman and CEO Dr. Albert Bourla said in a statement.

"We continue to move at the speed of science to compile all the data collected thus far and share with regulators around the world. With hundreds of thousands of people around the globe infected every day, we urgently need to get a safe and effective vaccine to the world."

Pfizer said the 95% efficacy rate applied to all ages and races participating in the 40,000-person study, and side effects were described as negligible.

Monday, Moderna said interim results from its final-stage study showed its competing vaccine was also close to 95% effective.

Both vaccines are based on "messenger RNA" technology, in which genetic sequences are used to "trick" the body into turning on cells to fight or prevent a given disease.

Pfizer has said it will manufacture 50 million doses of the vaccine this year and more than a billion doses next year.