'Great day for science and humanity': Pfizer reports 90% efficacy in interim analysis of COVID-19 vaccine

Pfizer and BioNTech announced that their mRNA-based vaccine candidate, BNT162b2, against SARS-CoV-2 has demonstrated evidence of efficacy in trial participants, based on the first interim efficacy analysis.

The early analysis, conducted on Nov. 8 by an external, independent Data Monitoring Committee (DMC) from the Phase 3 clinical study, found a vaccine efficacy rate above 90 percent.

After discussion with the FDA, Pfizer and BioNTech recently elected to drop the 32-case interim analysis and conduct the first interim analysis at a minimum of 62 cases.The evaluable case count reached 94 and the DMC performed its first analysis, concluding that the case split between vaccinated individuals and those who received the placebo indicates a vaccine efficacy rate above 90 percent, at 7 days after the second dose.

“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,” said Dr. Albert Bourla, Pfizer Chairman and CEO.

The Phase 3 clinical trial of BNT162b2 began on July 27 and has enrolled 43,538 participants to date, 38,955 of whom have received a second dose of the vaccine candidate as of Nov. 8. The trial is continuing to enroll and is expected to continue through the final analysis when a total of 164 confirmed COVID-19 cases have accrued. According to the companies, they should have the amount of safety data specified by the FDA in its guidance for potential Emergency Use Authorization available by the third week of November.

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