Coronavirus disease 2019 (COVID-19) is raging. On Nov. 8, 2020, at least 103,657 new cases and 464 deaths were reported in the United States. Over the past week, there has been an average of 111,175 cases per day, an increase of 59% from the average just 2 weeks ago. Although well below peak spring levels, deaths averaged more than 800 per day in early November, far more than were reported in early July 2020.
A vaccine is perhaps the best hope for ending the pandemic. Currently, there is no vaccine to prevent infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but researchers have been racing to develop one.
Now, based on an interim efficacy analysis, Pfizer andBioNTech claim their messenger ribonucleic acid (mRNA)-based vaccine was more than 90% effective in preventing COVID-19 in participants who had not previously been infected with SARS-CoV-2.
The Phase 1/2/3 clinical trial was designed to evaluate the safety, tolerability, immunogenicity, and efficacy of RNA vaccine candidates against COVID-19 in healthy individuals.
The Phase 3 trial of BNT162b2 began on July 27, 2020, 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% of global participants and 30% of US participants are of diverse backgrounds. 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 trial also will evaluate the potential for the vaccine candidate to provide protection against COVID-19 in those who have had previous 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 7 days after the second dose, the final analysis now will include, with the approval of the U.S. Food and Drug Administration, new secondary endpoints evaluating efficacy based on cases accruing 14 days after the second dose as well. The addition of these secondary endpoints hopefully will help align data across all COVID-19 vaccine studies and allow for cross-trial learnings and comparisons between these novel vaccine platforms.
If approved, the vaccine will require patients to receive two shots, with the second coming 21 days after the first.
The sprint for a vaccine could bring a new technique to the fore, using mRNA. If successful, the treatment would be the first commercially available mRNA vaccine. An mRNA vaccine encodes proteins of a virus, which is inserted into a cell to trigger an immune response and create antibodies. Although there has never been a successful mRNA vaccine before, studies show they can elicit immunity against flu, Zika, rabies, and coronavirus. The advantage of mRNA vaccines is that they are non-infectious and could be produced quickly at large scale.
