COVID-19 vaccine more than 90% effective, Pfizer says
A vaccine candidate developed by Pfizer and BioNTech was more than 90% effective in preventing COVID-19 and showed no serious safety concerns, according to an interim analysis of phase 3 clinical trial results released by the companies.
Pfizer and BioNTech said they plan to submit the mRNA-based vaccine candidate, now called BNT162b2, to the FDA for an emergency use authorization after a required safety milestone is met, likely in the third week of November.
“This is great news,” Florian Krammer, PhD, a professor of vaccinology at the Icahn School of Medicine at Mount Sinai in New York, told Healio. “There are many open questions, but we now might have a tool to mitigate the effects of this pandemic. This is also good news for the other vaccine candidates.”
The analysis, which was conducted by an external and independent data monitoring committee, evaluated 94 confirmed cases of COVID-19 among more than 43,000 participants enrolled in the global trial, including more than 38,000 who have received two doses of the vaccine candidate. Around 42% of participants globally and 30% in the United States are from racially and ethnically diverse backgrounds, the companies said.
At 7 days after the second dose, the vaccine was more than 90% effective compared with placebo among participants with no prior exposure to SARS-CoV-2.
“This means that protection is achieved 28 days after the initiation of the vaccination, which consists of a 2-dose schedule. As the study continues, the final vaccine efficacy percentage may vary,” the companies said.
The trial continues to enroll participants and is expected to continue through the final analysis, when a total of 164 confirmed COVID-19 cases have accrued, they said.
The vaccine candidate also will be evaluated among participants who have had prior exposure to SARS-CoV-2, and to test its efficacy in preventing severe COVID-19 illness. It is one of several COVID-19 vaccine candidates to reach phase 3 development in the U.S.
Pfizer and BioNTech expect to produce up to 50 million doses of the vaccine globally by the end of the year and up to 1.3 billion doses in 2021.
Discussions about who will be prioritized to receive a COVID-19 vaccine first when one is available have begun. The CDC’s Advisory Committee on Immunization Practices listed four groups as potential early COVID-19 vaccine recipients, including health care personnel, other nonmedical essential workers, people with high-risk medical conditions and adults aged 65 years or older.
Pfizer recently announced that it received approval from the FDA to begin enrolling children aged as young as 12 years in the trial to determine the safety and efficacy of the vaccine in adolescents.