Pfizer and German mRNA biotech partner BioNTech have released an early look at their experimental pandemic vaccine, and the news is good.
The pair’s mRNA-based vaccine candidate, BNT162b2, has shown in its closely watched phase 3 that it was more than 90% effective in preventing COVID-19 in participants without evidence of prior SARS-CoV-2 infection in the first interim efficacy analysis.
This is a big deal, given that most saw 50% to 70% effectiveness as a strong win; 90% is likely the best case for the vaccine, and Pfizer cautioned that as more data come in, this could change. The data are based on a two-shot dosing schedule, and the 90% figure comes 28 days after the initial dose.
These data come after some change-ups in the protocol as well as an unexpected chat with the FDA. Pfizer had been expected to release the data in October, with the interim analysis based on 32 cases.
But after a “discussion with the FDA, the companies recently elected to drop the 32-case interim analysis and conduct the first interim analysis at a minimum of 62 cases,” Pfizer said in a statement.
However, by the time this had been sorted out, data from 94 patients were used. The trial only started in July but has already enrolled nearly 44,000 patients. It remains ongoing, and Pfizer will need to hit data from 164 patients and build up at least two months’ worth of safety data before it can ask the FDA for an emergency use OK.
This will bring it to around Thanksgiving when it could feasibly ask for an emergency use authorization. Pfizer said it could get out around 50 million doses this side of 2021, jumping to 1.3 billion next year. That 50 million is not huge, and that would only be used for 25 million people on a two-dose schedule.
The vaccine also needs to be stored at very cold temperatures, but logistics and storage are added issues Pfizer is confident it can handle.
There are, as ever, caveats. These are small numbers—fewer than 100 patients assessed, and the companies haven’t broken down how many got the vaccine and who didn’t. We also don’t know, based on these data, whether it can stop severe cases or even deaths. Detailed safety data were not revealed, though previously the shot appeared to cause mild side effects, such as fever and muscle aches, which resolved.
“The DMC has not reported any serious safety concerns and recommends that the study continue to collect additional safety and efficacy data as planned,” Pfizer said of safety. It will, however, remain an issue to be closely assessed, as no mRNA vaccine has ever been approved in the world before.
It in addition hasn’t been peer reviewed; this isn’t unusual in 2020, but a factor that must always be added into calculations over efficacy and safety. A full breakdown of the data in a peer-reviewed journal is planned.
“Today is a great day for science and humanity,” said Albert Bourla, Ph.D., Pfizer chairman and CEO, with more than a little grandiosity.
“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,” he said. “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. 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.”
Pfizer’s stock soared nearly 15% premarket, with BioNTech up 25%. The vaccine is already on a rolling submission in Europe.
This also sparked a major rally for the FTSE 100, which was around 5% higher in early afternoon deals which analysts ascribed to the positivity around Pfizer’s vaccine.
Analysts at Leerink said the data “look very promising and we think should beat expectations of most investors and the market, and should provide a welcome boost to sentiment going into an epidemiologically challenging winter season.”