- Dr. Albert Bourla, chairman and CEO of Pfizer, hailed the trial results as a "great day for science and humanity."
- Pfizer and BioNTech said the case split between vaccinated individuals and those who received a placebo indicated a vaccine efficacy rate of above 90% at seven days after the second dose.
- It means that protection from Covid-19 is achieved 28 days after the initial vaccination, which consists of a two-dose schedule.
Pfizer and BioNTech announced Monday their coronavirus vaccine was more than 90% effective in preventing Covid-19 among those without evidence of prior infection, hailing the development as "a great day for science and humanity."
"I think we can see light at the end of the tunnel," Pfizer Chairman and CEO Dr. Albert Bourla told CNBC's Meg Tirrell on "Squawk Box." "I believe this is likely the most significant medical advance in the last 100 years, if you count the impact this will have in public health, global economy."
The announcement comes as drugmakers and research centers scrambled to deliver a safe and effective vaccine to help bring an end to the coronavirus pandemic that has claimed over 1.2 million lives worldwide.
Scientists are hoping for a coronavirus vaccine that is at least 75% effective, while White House coronavirus advisor Dr. Anthony Fauci has said one that is 50% or 60% effective would be acceptable.
U.S. stock futures skyrocketed as investors cheered the news. Futures on the Dow Jones Industrial Average surged 1,646 points, implying an opening gain of more than 1,630 points. By late morning, the Dow was up more than 1,000 points, a rise of 3.7%.
Airline and cruise company stocks jumped in premarket trading — with some stocks rising by 20% and 30%. Both industries have been significantly affected by the global health crisis as travel restrictions and a resurgence in outbreaks continue to hurt demand.
Pfizer's results were based on the first interim efficacy analysis conducted by an external and independent Data Monitoring Committee from the phase three clinical study. The independent group of experts oversees U.S. clinical trials to ensure the safety of participants.
The analysis evaluated 94 confirmed Covid-19 infections among the trial's 43,538 participants. Pfizer and the U.S. pharmaceutical giant's German biotech partner said the case split between vaccinated individuals and those who received a placebo indicated a vaccine efficacy rate of above 90% at seven days after the second dose.
It means that protection from Covid-19 is achieved 28 days after the initial vaccination, which consists of a two-dose schedule. The final vaccine efficacy percentage may vary, however, as safety and additional data continue to be collected.
Dr. Scott Gottlieb, a former FDA commissioner and a member of Pfizer's board, told CNBC the vaccine could be available in limited use as early as late December and widely available by the third quarter of 2021.
"The first set of results from our Phase 3 COVID-19 vaccine trial provides the initial evidence of our vaccine's ability to prevent COVID-19," Bourla said in a statement.
"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," Bourla continued.
"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."
Roughly 42% of the trial's global participants had racially and ethnically diverse backgrounds, Pfizer and BioNTech said, adding that there haven't been any serious safety concerns reported yet.
The companies said they planned to submit for emergency use authorization to the U.S. Food and Drug Administration soon after they have two months of data, which is currently on track for the third week of November.
Based on current projections, Pfizer and BioNTech expect to produce up to 50 million vaccine doses in 2020, and up to 1.3 billion doses in 2021. The vaccine requires two doses per person. Though the companies didn't take any money from the federal government for research and development for the drug, they reached a nearly $2 billion agreement in July to supply 100 million doses to the U.S. government as part of the Trump administration's Operation Warp Speed. That money is helping with manufacturing and distribution.
Plans to deliver hundreds of millions of coronavirus vaccines around the world raise questions about logistics and distribution in part because of the need to store and transport them in supercooled containers.
The company reportedly plans to load suitcase-sized boxes from distribution sites in Kalamazoo, Michigan, and Puurs, Belgium, onto as many as two dozen trucks per day, allowing for the daily transit of roughly 7.6 million doses to nearby airports.
The companies said they plan to submit data from the full phase three trial, which began on July 27, for scientific peer-review publication.
"The U.S. FDA set a threshold of 50% effectiveness for a Covid-19 vaccine to merit approval. A 90% effective vaccine would be extraordinary," Dr. Peter Drobac, a global health physician and director of the Skoll Centre for Social Entrepreneurship at the University of Oxford, said via email.
"We'll need to see the full results subjected to independent review. Let's take a deep breath, but this is very promising news," he added.
U.S. officials and scientists are hopeful a vaccine to prevent Covid-19 will be ready in the first half of 2021 — 12 to 18 months since Chinese scientists first identified the coronavirus and mapped its genetic sequence.
It's a record-breaking time frame for a process that normally takes about a decade for an effective and safe vaccine. The fastest-ever vaccine development, mumps, took more than four years and was licensed in 1967.
A more than 90% effective coronavirus vaccine would be roughly on par with one dose of a measles vaccination, which is about 93% effective, according to the Centers for Disease Control and Prevention.
Comparatively, the CDC says a vaccine for influenza reduces the risk of flu illness by between 40% and 60% among the overall population.
— CNBC's Berkeley Lovelace Jr. contributed to this report.
Disclosure: Scott Gottlieb is a CNBC contributor and is a member of the boards of Pfizer, genetic testing start-up Tempus and biotech company Illumina. Gottlieb also serves as co-chair of Norwegian Cruise Line Holdings′ and Royal Caribbean's "Healthy Sail Panel."
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