Pharmaceutical giant, Pfizer announced on Monday that an early analysis of its coronavirus vaccine trial suggested the vaccine was robustly effective in preventing Covid-19, a promising development as the world has waited anxiously for any positive news about a pandemic that has killed more than 1.2 million people.
Pfizer, which developed the vaccine with the German drugmaker BioNTech, released only sparse details from its clinical trial, based on the first formal review of the data by an outside panel of experts.
The company said that the analysis found that the vaccine was more than 90 percent effective in preventing the disease among trial volunteers who had no evidence of prior coronavirus infection. If the results hold up, that level of protection would put it on par with highly effective childhood vaccines for diseases such as measles. No serious safety concerns have been observed, the company said.
Pfizer plans to ask the Food and Drug Administration for emergency authorization of the two-dose vaccine later this month, after it has collected the recommended two months of safety data. By the end of the year it will have manufactured enough doses to immunize 15 million to 20 million people, company executives have said.
This is a historical moment,” said Kathrin Jansen, a senior vice president and the head of vaccine research and development at Pfizer. “This was a devastating situation, a pandemic, and we have embarked on a path and a goal that nobody ever has achieved — to come up with a vaccine within a year.”
The news comes just days after Joseph R. Biden Jr. clinched a victory over President Trump in the presidential election. Mr. Trump had repeatedly hinted a vaccine would be ready before Election Day, Nov. 3. This fall, Pfizer’s chief executive, Dr. Albert Bourla, frequently claimed that the company could have some indication of whether the vaccine worked by October, something that did not come to pass.
Stocks surged on the news. The S&P 500 gained 1.2 percent Monday, ending the day just short of a high reached in early September. Shares of companies that stand to gain most from the return of normal activity — like airlines and shopping mall operators — soared, while those whose businesses were well suited under lockdowns were sharply lower.
Independent scientists have however cautioned against hyping early results before long-term safety and efficacy data has been collected. And no one knows how long the vaccine’s protection might last. Still, the development makes Pfizer the first company to announce positive results from a late-stage vaccine trial, vaulting it to the front of a frenzied global race that began in January and has unfolded at record-breaking speed.