Pfizer’s COVID-19 Vaccine Is Actually 95% Effective, New Data Shows

Pfizer and BioNTech recently announced that they concluded their Phase 3 clinical trial after their mRNA-based COVID-19 vaccine candidate, BNT162b2, met all of the study’s primary efficacy endpoints. 

Overall, BNT162b2 elicited a vaccine efficacy rate of 95 percent efficacy in participants without prior SARS-CoV-2 infection, as well as with and without prior SARS-CoV-2 infection, which was the second primary objective. 

The first primary objective analysis was based on 170 cases of COVID-19, of which 162 cases were observed in the placebo group and eight were observed in the BNT162b2 group.

In all, there were 10 severe cases of COVID-19 observed in the trial: nine in the placebo group, and one in the BNT162b2 group.

Researchers noted that each case was measured seven days after the second dose and efficacy rate was consistent across all age, gender, and race groups. They also saw 94 percent efficacy in adults over 65 years of age. 

“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,” Albert Bourla, Pfizer chairman and CEO, said in the announcement. 

“We continue to move at the speed of science to compile all the data collected thus far and share with regulators around the world. 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,” he continued. 

A separate review of reactogenicity data from the final analysis, which consisted of 8,000 randomized participants 18 years and older in the phase 2/3 study, showed that the vaccine was well tolerated.

The only severe events reported were fatigue (3.8 percent) and headache (2 percent). The Grade 3, or severe, adverse events were resolved shortly after vaccination. 

Older adults reported fewer and milder adverse events following vaccination overall. 

“We are grateful that the first global trial to reach the final efficacy analysis mark indicates that a high rate of protection against COVID-19 can be achieved very fast after the first 30 µg dose, underscoring the power of BNT162 in providing early protection,” said Ugur Sahin, MD, CEO and co-founder of BioNTech.

Pfizer and BioNTech stated that they plan to submit a request to FDA for an emergency use authorization based on the total safety and efficacy data collected. The companies also plan to submit manufacturing data regarding the quality of the candidate per the agency’s requirements for application. 

The companies expect to produce up to 50 million vaccine doses globally in 2020 and up to 1.3 billion doses by the end of 2021. 

“These achievements highlight the potential of mRNA as a new drug class,” Sahin continued. 

“Our objective from the very beginning was to design and develop a vaccine that would generate rapid and potent protection against COVID-19 with a benign tolerability profile across all ages. 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,” he stated. 

At the end of April, Pfizer and BioNTech teamed up to advance COVID-19 vaccine development, and in late July, the companies announced the start of a global Phase 2/3 clinical trial of BNT162b2, from their BNT162 mRNA-based vaccine program.

Just four months later, BNT162b2 demonstrated evidence of efficacy against COVID-19 in participants without prior evidence of SARS-CoV-2 infection.

Specifically, the candidate was found to be more than 90 percent effective in preventing the coronavirus in these patients.