Pfizer, BioNTech announce vaccine candidate success in early analysis

Pharmaceutical giants Pfizer and BioNTech announced this morning that its vaccine candidate was found to be more than 90 percent effective in preventing the novel coronavirus (COVID-19) in participants without evidence of prior SARS-CoV-2 infection in the first interim efficacy analysis conducted by an independent Data Monitoring Committee (DMC).

The mRNA-based vaccine candidate, BNT162b2, is currently in Phase 3 clinical study. In the analysis, the case split between vaccinated individuals and those who received the placebo indicates a vaccine efficacy rate above 90 percent, at seven days after the second dose. This means that protection is achieved 28 days after the initiation of the vaccination, which consists of a two-dose schedule, the experts said.

After consulting with the U.S. Food and Drug Administration, the companies said they elected to drop the typical 32-case interim analysis and conduct the first interim analysis at a minimum of 62 cases. In total, they conducted the analysis on 94 cases, according to the statement.

As the study continues, the final vaccine efficacy percentage may vary. The DMC has not reported any serious safety concerns and recommends that the study continue to collect additional safety and efficacy data as planned. The data will be discussed with regulatory authorities worldwide, the companies said.

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 November 8, 2020. Approximately 42 percent of global participants and 30 percent of U.S. participants have racially and ethnically diverse backgrounds, according to the study.

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

In addition to the primary efficacy endpoints evaluating confirmed COVID-19 cases accruing from seven days after the second dose, the final analysis now will include, with the approval of the FDA, new secondary endpoints evaluating efficacy based on cases accruing 14 days after the second dose as well. The companies said they believe that the addition of these secondary endpoints will help align data across all COVID-19 vaccine studies and allow for cross-trial learnings and comparisons between novel vaccine platforms. 

Editor's note: Click here for more information and ongoing COVID-19 updates for integrative healthcare professionals.