Pfizer announced Monday morning that late-stage clinical trial data show that its vaccine candidate is over 90 percent effective in preventing COVID-19.
The announcement was widely greeted as a sorely needed positive development in the fight against the virus, which is raging across the country.
The drugmaker said it conducted an analysis of 94 confirmed cases in trial participants after enrolling 43,538 participants in a larger study. The company added that it hopes to have the amount of safety data required for a Food and Drug Administration (FDA) Emergency Use Authorization by the third week of November.
The vaccine requires two doses, and protection was achieved 28 days after the first dose, Pfizer said.
“We are reaching this critical milestone in our vaccine development program at a time when the world needs it most with infection rates setting new records, hospitals nearing over-capacity and economies struggling to reopen,” Pfizer Chairman and CEO Albert Bourla said in a statement.
“With today’s news, we are a significant step closer to providing people around the world with a much-needed breakthrough to help bring an end to this global health crisis. We look forward to sharing additional efficacy and safety data generated from thousands of participants in the coming weeks,” he added.
Pfizer cannot immediately apply for emergency authorization from the FDA, because under administration guidelines, it needs to wait to have two months-worth of safety data on the vaccine, which will be by the third week of November.
“There is some pretty fabulous news out today on the vaccine front,” tweeted Ashish Jha, dean of the Brown University School of Public Health, while cautioning he needs to see the full data. “I am pleasantly surprised.”
While high-risk groups like health care workers and the elderly could get the vaccine later this year, experts have widely said the general public is not expected to get a vaccine until sometime several months into 2021.
The FDA guidelines had set a minimum of 50 percent effectiveness for a vaccine to be approved, meaning Pfizer’s would easily clear that bar. The company has not yet published its full data, which experts will be waiting to analyze.
Distributing a vaccine to hundreds of millions of people, however, is a daunting undertaking on its own.
The vaccine announcement had been caught up in politics to some extent as President Trump pushed for approval before Election Day. It ultimately became clear that was not possible, given the FDA’s standard for two months of safety data, and Pfizer did not report any data on effectiveness before Election Day either. Bourla, the Pfizer CEO, repeatedly pledged that politics would have nothing to do with the timing of the vaccine.
Pfizer and German firm BioNTech said on Monday that they intend to submit full phase 3 trial data for peer review. The companies project they will produce up to 50 million doses globally by the end of this year and as many as 1.3 billion doses in 2021.