Pfizer said the vaccine developed with German partner BioNTech SE showed consistent efficacy across age and ethnicity demographics. There were also no major side effects, making it deployable worldwide.
The vaccine reportedly showed 94% effective for adults over 65 years, who are at particular risk from COVID-19.
Pfizer said there had been 170 infections in its trial of more than 43,000 volunteers. Of that number, 162 were observed in the placebo arm, and 8 were in the vaccine group.
Ten participants developed severe COVID-19, one of whom received the vaccine.
The company said the vaccine’s side effects were mostly mild to moderate and cleared up quickly.
The trial also showed that more than 2% of those vaccinated experienced fatigue, while 3.7% of recipients experienced the side effect after the second dose. Older adults tended to report fewer and milder solicited adverse events following vaccination.
Pfizer ends vaccine trial with 95% efficacy
“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 CEO Albert Bourla said in a statement.
Pfizer said it expects to make as many as 50 million vaccine doses this year, which could immunize 25 million people and produce up to 1.3 billion doses in 2021.
The final results were released just one week after Pfizer announced its initial results from the trial showing the vaccine was more than 90% effective. Moderna Inc. on Monday its vaccine was 94.5% effective based on the preliminary data.
“In a trial of 30,000 subjects, where we already received some 95 cases of infections. In those, 90 of them were in the population that did not receive the vaccine, and only five were the only infections that did. That is where the 94.5 percent protection comes from,” said Noubar Afeyan, Moderna co-founder and chairman.
Compared to Pfizer, Afeyan said that Moderna’s innovations enable it to “keep the vaccine under refrigeration conditions for up to 30 days,” enabling broad distribution.
Afeyan said around 10 to 20 million doses would be distributed through the supply chain before the end of 2020 and around 50 million doses by the first quarter of 2021.