By Jared S. Hopkins
An experimental Covid-19 vaccine from Pfizer Inc. and BioNTech SE was 95% effective in final results from a pivotal study and is showing signs of being safe, key pieces of data as the companies prepare to ask health regulators to authorize use.
Pfizer /zigman2/quotes/202877789/composite PFE -0.43% plans to seek authorization for the vaccine within days, the companies said Wednesday, leaving the shot on track to go into distribution by the end of the year if health regulators permit.
Out of 170 adult volunteers in the nearly 44,000-subject trial who developed Covid-19 with at least one symptom, 162 received a placebo, while eight got the vaccine, Pfizer and BioNTech /zigman2/quotes/214419716/composite BNTX -1.06% said.
The resulting 95% effectiveness rate puts the shot’s performance on par with shingles and measles vaccines. It is also consistent with the vaccine’s showing in a peek last week at how it did in an analysis of the first 94 subjects to fall sick.
Researchers haven’t found any serious safety issues, the companies said. The vaccine appeared to be well tolerated following a review of data from 8,000 study subjects, the companies said.
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