Pfizer-BioNTech COVID Vaccine Efficacy High at 6 Months, Companies Report

The COVID-19 vaccine partners announced an efficacy rate of >90% for BNT162b2 among 12 000 trial participants at up to 6 months after the second dose.

COVID-19 vaccine manufacturing partners Pfizer and BioNTech today announced that their vaccine, BNT162b2, remains highly effective at 6 months after the second dose.

The updated topline results from ongoing analysis of 12 000 of the >44 000 adults in the pivotal phase 3 clinical trial, showed the vaccine 91.3% effective against COVID-19 infection as observed from 7 days up to 6 months after the second dose.

Of 927 confirmed COVID-19 cases detected through March 13, 77 were among people who received the vaccine and 850 were among those who received placebo.

Importantly, the analysis also found the vaccine was 100% effective in preventing COVID-19 cases in South Africa where the B.1.351 variant of the virus is widely circulating.

“The high vaccine efficacy observed through up to six months following a second dose and against the variant prevalent in South Africa provides further confidence in our vaccine’s overall effectiveness,” said Albert Bourla, chairman and CEO of Pfizer.

BNT162b2 protection against severe disease as defined by the US Centers for Disease Control and Prevention was 100% and as defined by the us Food and Drug Administration, 95.3%. Safety and tolerability profiles also have been favorable among the 12 000 trial participants with follow-up of at least 6 months post full vaccination.

The favorable data seen in longer-term follow up (vs follow-up in initial clinical trials) is essential to support confidence in the global vaccination efforts now under way, observed BioNTech CEO Ugur Sahin in the companies' statement.

“These data also provide the first clinical results that a vaccine can effectively protect against currently circulating variants, a critical factor to reach herd immunity and end this pandemic for the global population," said Sahin.

The announcement comes one day after the companies jointly announced BNT162b2 efficacy of 100% among youths aged 12 to 15 years.

Pfizer and BioNTech plan to provide more detailed data shortly to the US FDA and to global regulatory bodies.


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