WASHINGTON, April 2 — The ongoing phase three clinical trial of Pfizer-BioNTech’s COVID-19 vaccine showed its protection remains high for up to six months after the second dose, the two companies announced on Thursday.
Results from the analysis of 927 confirmed symptomatic cases of COVID-19 observed in their pivotal phase three study showed the Pfizer-BioNTech COVID-19 vaccine, BNT162b2, was 91.3 per cent effective against COVID-19, measured seven days through up to six months after the second dose, reported Xinhua news agency.
The vaccine was 100 per cent effective against severe disease as defined by the United States (US) Centres for Disease Control and Prevention, and 95.3 per cent effective against severe COVID-19 as defined by the US Food and Drug Administration (FDA), according to a joint statement of the two companies.
Safety data from the phase three study have been collected from more than 12,000 vaccinated participants who have a follow-up time of at least six months after the second dose, demonstrating a favourable safety and tolerability profile, said the statement.
“These data confirm the favourable efficacy and safety profile of our vaccine and position us to submit a Biologics License Application to the US FDA,” said Albert Bourla, chairman and chief executive officer of Pfizer.
“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 Ugur Sahin, CEO and co-founder of BioNTech.
The new results came a day after the two companies announced the vaccine has demonstrated 100 per cent efficacy and robust antibody responses in a trial in adolescents 12 to 15 years of age.
The trial enrolled 2,260 adolescents 12 to 15 years of age in the United States. In the trial, 18 cases of COVID-19 were observed in the placebo group versus none in the vaccinated group.
The vaccine elicited SARS-CoV-2-neutralising antibody geometric mean titers (GMTs) of 1,239.5, demonstrating strong immunogenicity in a subset of adolescents one month after the second dose, according to the companies.
The results exceeded those recorded earlier in vaccinated participants aged 16 to 25 years old, according to the trial data.
The two companies plan to submit these data to the FDA and the European Medicines Agency as soon as possible to request expansion of the Emergency Use Authorization and EU Conditional Marketing Authorization for BNT162b2.
The FDA authorised Pfizer-BioNTech COVID-19 vaccine for emergency use in the United States in December last year. The vaccine, the first that got FDA approval in the country, was authorised for use in individuals 16 years of age and older.