Final Analysis Suggests Pfizer, BioNTech’s COVID-19 Vaccine is Safe with 95% Efficacy

November 18th, 2020 – Pharma giant Pfizer and BioNTech announced today that their mRNA vaccine candidate BNT162b2 shows 95% efficacy and has met all of the primary efficacy endpoints in the Phase 3 trial. While the primary objective was to evaluate vaccine efficacy in study participants who haven’t been infected previously with COVID-19, the secondary objective was to measure the same in participants with and without prior infection, 7 days following the second dose.

Earlier, on November 9th, both companies announced a 90% vaccine efficacy based on an interim analysis conducted with 94 cases. However, the final efficacy analysis conducted with 170 cases has revealed a vaccine efficacy rate of 95% (p<0.0001). Of them, 162 cases of COVID-19 were observed in the placebo group compared to 8 cases in the vaccinated group. One of the study’s encouraging aspects is the observation of 94% efficacy in participants over 65 years of age who belong to the high-risk group.

“The study results mark an important step in this historic eight-month journey to bring forward a vaccine capable of helping to end this devastating pandemic. We continue to move at the speed of science to compile all the data collected thus far and share with regulators around the world,” said Dr. Albert Bourla, Chairman and CEO of Pfizer. “With hundreds of thousands of people around the globe infected every day, we urgently need to get a safe and effective vaccine to the world.”

No Safety Issues

Until now, around 41,135 participants out of 43,661 have received the second dose of BNT162b2 in the Phase 3 trial, which has been conducted in 150 sites spanning 6 countries, including 39 states in the US. Approximately 40% of the total participants are from diverse backgrounds, including 4.5% Asian, 10% Black, 26.1% Hispanic, and 0.8% Native American. Besides, 40.9% of them are between 56-85 years of age.

The data monitoring committee has not reported any safety issues and the final analysis shows that the vaccine was well tolerated. The only Grade 3 adverse events were fatigue (3.8%) and headache (2.0%) following the second dose. The trial will continue to evaluate the safety and efficacy for another two years.

Emergency Use Authorization (EUA)

In light of achieving the safety milestones set by the U.S. Food and Drug Administration (FDA), both companies are now planning to apply for Emergency Use Authorization (EUA). Besides, they are also planning to share the data with other regulatory agencies worldwide. The vaccine is already under a rolling submission status by the European Medicines Agency (EMA). If greenlighted by the FDA, BNT162b2 would be the first-ever mRNA vaccine to be approved for any disease.

“These achievements highlight the potential of mRNA as a new drug class,” said Ugur Sahin, M.D., CEO and Co-founder of BioNTech. “We believe we have achieved this with our vaccine candidate BNT162b2 in all age groups studied so far and look forward to sharing further details with the regulatory authorities. I want to thank all the devoted women and men who contributed to this historically unprecedented achievement. We will continue to work with our partners and governments around the world to prepare for global distribution in 2020 and beyond.”

Global Distribution

With a positive result under its belt, Pfizer and BioNTech now have a sizeable lead over its competitor, Moderna’s mRNA-1273, in the vaccine race. Moderna announced the interim analysis of mRNA-1273 claiming 94.5% efficacy only a couple of days earlier. Both candidates use the messenger RNA to elicit the body’s immune response and produce protective antibodies against the SARS-CoV-2 virus.

However, Moderna will hold the edge during the long term storage and global distribution of its vaccine. This is because the improved stability of mRNA-1273 enables it to withstand temperatures of 2°C to 8°C for 30 days in contrast to the -70°C and -80°C freezing requirements for BNT162b2. As a result, in countries such as India, the government is mulling over the use of Pfizer and BioNTech’s vaccine, if at all, it becomes available.

“The arrangement of cold-chains for storing the vaccine developed by Pfizer at a low temperature of -70°C is a big challenge, and it will not be easy for any nation. But then, if at all it has to be obtained, we are examining what we need to do…and will work out a strategy,” said NITI Aayog member (Health), Dr. VK Paul, who also heads India’s National Task Force on COVID-19.

However, Pfizer and BioNTech are confident that their specially designed, temperature-controlled thermal shippers will maintain a temperature of -70°C±10°C and they can be used be as temporary storage units for 15 days by refilling with dry ice.

By Rajaneesh K. Gopinath, Ph.D.

Related Article: How Does Moderna’s mRNA Vaccine Measure Up to Pfizer’s?

References

1. https://www.pfizer.com/news/press-release/press-release-detail/pfizer-and-biontech-conclude-phase-3-study-covid-19-vaccine
2. https://www.livemint.com/news/world/centre-examining-all-possible-storage-facilities-for-pfizer-s-covid-19-vaccine-11605657834989.html

Author

Rajaneesh K. Gopinath