Pfizer Inc. said Monday that its COVID-19 vaccine may be a remarkable 90% effective, based on early and incomplete test results that nevertheless brought a big burst of optimism to a world desperate for the means to finally bring the catastrophic outbreak under control.
The announcement came less than a week after an election seen as a referendum on President Donald Trump’s handling of the scourge, which has killed more than 1.2 million people worldwide, including almost a quarter-million in the United States alone.
“We’re in a position potentially to be able to offer some hope,” Dr. Bill Gruber, Pfizer’s senior vice president of clinical development, told The Associated Press. “We’re very encouraged.”
Pfizer, which is developing the vaccine with its German partner BioNTech, now is on track to apply later this month for emergency-use approval from the U.S. Food and Drug Administration, once it has the necessary safety information in hand.
Even if all goes well, authorities have stressed it is unlikely any vaccine will arrive much before the end of the year, and the limited initial supplies will be rationed.
Dr. Anthony Fauci, the U.S. government’s top infectious-disease expert, said the results suggesting 90% effectiveness are “just extraordinary,” adding: “Not very many people expected it would be as high as that.”
“It’s going to have a major impact on everything we do with respect to COVID,” Fauci said as Pfizer appeared to take the lead in the all-out global race by pharmaceutical companies and various countries to develop a well-tested vaccine against the virus.
Dr. Bruce Aylward, the World Health Organization’s senior adviser, said Pfizer’s vaccine could “fundamentally change the direction of this crisis” by March, when the U.N. agency hopes to start vaccinating high-risk groups.
Global markets, already buoyed by the victory of President-elect Joe Biden, rocketed on the news from Pfizer. The S&P 500 was up 3.3% in afternoon trading, while the Dow Jones Industrial Average gained more than 1,300 points. Pfizer jumped more than 11%. Other vaccine stocks were up as well.
Still, Monday’s announcement doesn’t mean for certain that a vaccine is imminent: This interim analysis, from an independent data monitoring board, looked at 94 infections recorded so far in a study that has enrolled nearly 44,000 people in the U.S. and five other countries.
Some participants got the vaccine, while others got dummy shots. Pfizer released no specific breakdowns, but for the vaccine to be 90% effective, nearly all the infections must have occurred in placebo recipients. The study is continuing, and Pfizer cautioned that the protection rate might change as more COVID-19 cases are added to the calculations.
