Pfizer’s COVID-19 Vaccine Is Over 90% Effective, Early Data Shows

Pfizer and BioNTech recently announced that their mRNA-based COVID-19 vaccine candidate, BNT162b2, demonstrated evidence of efficacy against coronavirus in participants without prior evidence of SARS-CoV-2 infection. 

Specifically, BNT162b2 was found to be more than 90 percent effective in preventing COVID-19 in participants without evidence of prior SARS-CoV-2 infection.

“Today is a great day for science and humanity. 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,”  Albert Bourla, MD, Pfizer chairman and CEO, said in the announcement.  

“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,” Bourla continued. “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.” 

On March 17, Pfizer and BioNTech signed a letter of intent to co-develop and distribute potential COVID-19 vaccines through BioNTech’s mRNA vaccine program. 

Then in May, the companies dosed the first participant in a Phase 1/2 clinical trial for the BNT162 vaccine program to prevent COVID-19. The Phase 1/2 study enrolled about 360 individuals into two age cohorts, 18 to 55 and 65 to 85 years of age to uncover the safety, immunogenicity, and necessary dose level of four mRNA vaccine candidates. 

At the beginning of July, preliminary data showed that BNT162b1 could be administered in a dose that was well tolerated and generated dose-dependent immunogenicity. 

Just a week later, HHS and the Department of Defense (DoD) announced an agreement with Pfizer for large-scale production and nationwide delivery of 100 million doses of BNT162b2 in the US.

Under the agreement, the government will pay Pfizer and BioNTech $1.95 billion upon the receipt of the first 100 million doses. 

Then on July 30, the companies initiated the start of a global Phase 2/3 safety and efficacy study to evaluate BNT162b2. 

The trial enrolled 43,538 participants, 38,955 of whom have received a second dose of the vaccine candidate as of November 8, 2020. 

The study also will evaluate the potential for BNT162b2 to provide protection against COVID-19 in those who have had prior exposure to SARS-CoV-2 and vaccine prevention against severe COVID-19 disease. 

Most recently, Pfizer and BioNTech shared that seven days after a second 30 microgram dose of BNT162b2, the vaccine elicited SARS-CoV-2 neutralizing geometric mean titers (GMTs) in younger adults that were 3.8 times the GMT of 38 sera of SARS-CoV-2 convalescent patients and 1.6 times the GMT of the same panel. 

This proved that BNT162b2 was well-tolerated among all younger and older patients.

Pfizer noted in the recent announcement that the final analysis now will include new secondary endpoints evaluating efficacy based on cases after 14 days, a Pfizer spokesperson said. 

Both Pfizer and BioNTech noted that this addition of the secondary endpoints will help align data across all COVID-19 vaccine studies and allow for cross-trial learnings and comparisons between the vaccine platforms. 

“We will continue to collect further data as the trial continues to enroll for a final analysis planned when a total of 164 confirmed COVID-19 cases have accrued. I would like to thank everyone who has contributed to make this important achievement possible,” said Ugur Sahin, BioNTech co-founder and CEO.

Other top pharmaceutical companies, including Regeneron, AstraZeneca, and Johnson & Johnson, have also recently released positive results from ongoing trials of their COVID-19 vaccines.