An initial analysis of early data from Pfizer and BioNTech's clinical trial indicates its candidate COVID-19 vaccine is highly effective, the Washington Post reports.
The companies began the late-stage trial of their mRNA-based candidate vaccine in late July. According to a Pfizer press release, they have enrolled 43,538 participants into the study and there have been 94 COVID-19 cases among their participants. In their trial protocol, which was released in September, the companies said they would conduct their first analysis after 32 cases had arisen in their cohort. They had expected to have enough data for this by October, but announced then that they did not quite have the numbers. Further, the New York Times adds that the firms opted to wait until their second analysis point — 64 cases — to conduct their analysis after consulting with the US Food and Drug Administration and that even more cases then occurred during those discussions.
An outside panel has analyzed the companies' data to find that the candidate vaccine appears to be more than 90 percent effective in preventing COVID-19, the Post reports. Yale University's Akiko Iwasaki tells the Times this is a "spectacular number."
CNBC notes that scientists have been hoping for a vaccine that is 75 percent effective and that Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, has said that one that is only 50 percent or 60 percent effective could be acceptable. CNBC cautions that, as more data comes in, the percent efficacy of the Pfizer and BioNTech COVID-19 vaccine could change.
CNN adds that the vaccine appears to provide protection seven days after the second dose is administered and 28 days after the first.
Emory University's David Benkeser underscores at the Post the need for more data, adding it remains to be seen how long the vaccine's effect lasts and how well it prevents severe COVID-19.
Pfizer and BioNTech plan to submit an application for an Emergency Use Authorization for the vaccine to the FDA later this month, according to the Post, which adds that the trial is to continue to its end point of 164 cases.