Covid-19 vaccine candidate, BNT162b2, has prevented more than 90% of infections in a study of tens of thousands of volunteers in Phase 3 trials, the most encouraging scientific advance so far in the battle against the coronavirus."The mRNA-based vaccine candidate demonstrated evidence of efficacy against COVID-19 in participants without prior evidence of SARS-CoV-2 infection, based on the first interim efficacy analysis conducted on November 8, 2020 by an external, independent Data Monitoring Committee (DMC) from the Phase 3 clinical study," the company said in a statement.The preliminary results pave the way for the companies to seek an emergency-use authorization from regulators if further research shows the shot is also safe.Commenting.