Update, Nov. 18: More than a week after Pfizer and BioNTech reported that their two-dose COVID-19 vaccine was over 90 percent effective, an updated analysis of the clinical trial has showed promising new information. To start, the vaccine’s efficacy rate has increased to 95 percent seven days following the second dose. This, according to a news release that held much more detailed results than the initial one, was consistent across demographics like age, gender, race, and ethnicity. In people over 65, the efficacy rate decreased a bit to 94 percent. Though the analysis was done on those who had no evidence of previous infection, Pfizer said that this efficacy was observed “also in participants with and without prior SARS-CoV-2 infection.”
The initial analysis evaluated 94 people from the clinical trial who developed COVID-19. Now, the independent Data Monitoring Committee was able to evaluate a total of 170 cases (as a reminder, Pfizer had said it was waiting for at least 164 cases to fully evaluate). Of those 170 cases, 162 were reported in people who received a placebo and eight were seen in people who were vaccinated (aka, the less people in the vaccinated group who actually developed COVID-19, the better). Furthermore, nine of the COVID-19 cases from the placebo group were severe, as was one from the vaccinated group.
Again, no major safety concerns were reported, though some people did experience fatigue and headache after the second dose. This all means that Pfizer will be asking the FDA for emergency use authorization approval “within days.” According to The New York Times, this approval could take weeks.
The companies expect to produce up to 50 million doses this year and up to 1.3 billion doses by the end of next year, and Pfizer announced it launched a pilot delivery program to sort out eventual distribution in the US (note: remember, the vaccine needs to be stored at minus 70 degrees Celsius). The states involved in this program are Rhode Island, Texas, New Mexico, and Tennessee, according to Reuters, which also reported that these states will not receive vaccine doses earlier than others due to their participation in the pilot program. A news releases states, “Learnings from this program will be adapted for usage across other states to help them create effective immunization programs for this vaccine.”
This all comes soon after Moderna reported a 94.5-percent efficacy rate of its own COVID-19 vaccine.
Original post, Nov. 9: Pfizer reported on Monday, Nov. 9, that the COVID-19 vaccine research it has been spearheading with BioNTech since March shows promise; in the first formal review of its Phase 3 clinical trial, the vaccine was found to be more than 90 percent effective. Additionally, the companies said in a press release that the external, independent Data Monitoring Committee conducting the analysis also found zero serious safety concerns.
The vaccine is a two-dose vaccine administered about three weeks apart. It is mRNA based, meaning, as The New York Times explained, it “takes genetic material called messenger RNA and injects it into muscle cells, which treat it like instructions for building a protein – a protein found on the surface of the coronavirus. The proteins then stimulate the immune system and are believed to result in long-lasting protection against the virus.” The vaccine has to be stored in temperatures colder than winter in Antarctica (minus 70 degrees Celsius).
The committee’s analysis comes from 94 volunteers from the Phase 3 trial that began in late July and has enrolled over 43,000 participants worldwide. The 94 people evaluated developed COVID-19 but had no evidence of prior infection, and though we don’t know which volunteers received the placebo and which received the vaccine, the efficacy rate was calculated based on how many of those volunteers who developed COVID-19 took the two-dose vaccine and how many took the placebo. Given that the vaccine was proven to be at least 90 percent effective, most volunteers had to have been in the placebo group, and, as The New York Times stated, “we can safely assume very few people who were vaccinated got COVID-19.”
This data has not been published, let alone peer reviewed yet, and the initial 90-percent efficacy rate (at seven days after the second dose) could change as the trial continues on to its final analysis. That being said, the FDA has stated vaccines need to have a minimum effectiveness rate of 50 percent. Pfizer said it will extend the trial until there is data from 164 coronavirus-infected people as opposed to the 94 initially evaluated. Another caveat: it’s unclear how long immunity will last from the vaccine.
Related: Experts Explain Why a Vaccine Is the Only Safe Way to Achieve Herd Immunity For COVID-19
As the Phase 3 trial continues, it aims to evaluate the potential for the vaccine to protect against COVID-19 in people who had prior exposure to COVID-19 as well, the press release states, and aims to evaluate prevention against severe cases. Pfizer and BioNTech are expected to seek US emergency use authorization later this month.
This makes Pfizer the first company to announce positive results from a vaccine this late in trials, according to The New York Times. Company executives reportedly said that Pfizer will have manufactured enough doses by the end of the year to immunize up to 20 million people.
“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, DVM, PhD, 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.”
President-elect Joe Biden said that news of the Pfizer vaccine specifically does not change the fact that it could take a while before vaccines are widespread – and that this pandemic remains a serious threat. “America is still losing over 1,000 people a day from COVID-19, and that number is rising – and will continue to get worse unless we make progress on masking and other immediate actions,” a statement from Biden reads. “Today’s announcement promises the chance to change that next year, but the tasks before us now remain the same.”
Related: Moderna’s COVID-19 Vaccine Is 94.5% Effective and May Start Rolling Out in December
POPSUGAR aims to give you the most accurate and up-to-date information about the coronavirus, but details and recommendations about this pandemic may have changed since publication. For the latest information on COVID-19, please check out resources from the WHO, CDC, and local public health departments.