An experimental vaccine developed by Pfizer in association with BioNTech has been found 90% effective in preventing COVID-19 infection in participants who did not have a prior infection to the coronavirus.
The results were from the interim analysis of Phase III, or late-stage, study.
The vaccine candidate, called BTN162b2, is a messenger RNA–based vaccine that requires two doses. The Phase III clinical trial began on July 27, enrolling more than 43,500 participants so far, with over 40% of volunteers are from racially and ethnically diverse backgrounds.
Pfizer and BioNTech issued a press release in which they said over 38,950 trial volunteers had received the second dose of either their vaccine candidate or placebo as of November 8.
An interim analysis of more than 90 individuals found that the experimental vaccine was 90% effective 7 days after the second dose, meaning protection was achieved 28 days after receiving the first dose.
Dr. Paul Offit, who is a member of the FDA’s COVID-19 Vaccine Advisory Committee, told Medscape Medical News, “It’s promising in that it validates the genetic strategy — whether it is mRNA vaccines or DNA vaccines.”
“All of them have the same approach, which is that they introduce the gene that codes for the coronavirus spike protein into the cell. Your cell makes the spike protein, and your immune system makes antibodies to the spike protein,” he continued.
“At least in these preliminary data, which involved 94 people getting sick, it looks like it’s effective. That’s good,” Dr. Offit added. “We knew that it seemed to work in experimental animals, but you never know until you put it into people.”
So far, the independent data monitoring committee (DMC) has not reported any serious safety issues; however, the members of the committee said they will continue to collect safety and efficacy data as the trial progresses.
Pfizer and BioNTech plan to apply for the FDA’s Emergency Use Authorization (EUA) soon after the required safety milestone is achieved.
Dr. Albert Bourla, Pfizer CEO, said in a separate press release, “It’s important to note that we cannot apply for FDA Emergency Use Authorization based on these efficacy results alone. More data on safety is also needed, and we are continuing to accumulate that safety data as part of our ongoing clinical study.”
“We estimate that a median of two months of safety data following the second and final dose of the vaccine candidate ― required by FDA’s guidance for potential Emergency Use Authorization ― will be available by the third week of November,” he added.
Dr. Offit said that if Pfizer’s vaccine candidate is approved, its administration will be tricky. He said, “This particular vaccine has to be shipped and stored at –70° C or –80° C, which we’ve never done before in this country. That means maintaining the product on dry ice. That’s going to be a challenge for distribution, I think.”
Co-founder and CEO of BioNTech, Dr. Ugur Sahin, described the interim results as “a victory for innovation, science, and a global collaborative effort.”
“When we embarked on this journey 10 months ago this is what we aspired to achieve,” Dr. Sahin added. “Especially today, while we are all in the midst of a second wave and many of us in lockdown, we appreciate even more how important this milestone is on our path towards ending this pandemic and for all of us to regain a sense of normality.”
Even President-elect Joe Biden appreciated the findings, calling them “excellent news.”
Biden said, “At the same time, it is also important to understand that the end of the battle against COVID-19 is still months away. This news follows a previously announced timeline by industry officials that forecast vaccine approval by late November.”
“Even if that is achieved, and some Americans are vaccinated later this year, it will be many more months before there is widespread vaccination in this country.”
“Today’s news does not change this urgent reality,” Biden added. “Americans will have to rely on masking, distancing, contact tracing, hand washing, and other measures to keep themselves safe well into next year.” The article originally appeared on Medscape Medical News.
