Last week, Pfizer and BioNTech said their experimental COVID-19 vaccine was 90% effective in early interim results. And yesterday, they announced that their mRNA-based vaccine candidate is 95% effective at preventing COVID-19.

Dr. Reynold Panettieri Jr. of Robert Wood Johnson Medical School, New Brunswick, New Jersey, told Medscape Medical News, “This is a game-changer. The Pfizer data hit the critical number of patients, that was 170, and showed 95% success, which was stunning data.”

The clinical trial was ethnically diverse and its results were consistent across all genders and age groups, with a 94% efficacy seen in participants above 65 years of age.

Pfizer and BioNTech said they will now plan to file for the FDA’s emergency use authorization (EUA) after meeting all the FDA data endpoints.

Dr. Panettieri said, “I think things are going to go pretty smoothly for the EUA. The vaccine is also reportedly quite safe.”

Some participants reported a couple of side effects – fatigue and headache.

Dr. Moncef Mohamed Slaoui, Operation Ward Speed Chief Scientist, said, “We have a pretty good understanding of the short-term safety of these vaccines.”

“According to decades of FDA vaccine experience, more than 90% of side effects appear within 40 days of administration,” he added. “In addition to the FDA requirement to monitor 50% of vaccine trial participants for at least 60 days, there will be active pharmacovigilance for any adverse events after authorization.”

Just recently, Moderna Therapeutics announced that its coronavirus vaccine candidate has been found 94.5% effective at preventing COVID-19.

Alex Azar, Secretary of the U.S. Department of Health and Human Services (HHS), said, “We have reasons for optimism. Pending the FDA EUA, “we now have two safe and effective vaccines…ready to be distributed within weeks.”

“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,” said Pfizer CEO Albert Bourla. “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.”

Dr. Ugur Sahin, BioNTech CEO, said, “We are grateful that the first global trial to reach the final efficacy analysis mark indicates that a high rate of protection against COVID-19 can be achieved very fast after the first 30 µg dose, underscoring the power of BNT162 in providing early protection.”

Azar added, “Now is not the time for anyone to let their guard down,” emphasizing the need for washing hands, wearing facemasks in the public, practicing social distancing, and avoiding crowded indoor spaces.

He said, “Please do those things…there is such promising hope ahead. We want you all to get there so you can take advantage of it.” The article originally appeared on Medscape Medical News.