Pfizer says that more interim results from its ongoing coronavirus vaccine study suggest the shots are 95% effective and that the vaccine protects older people most at risk of dying from COVID-19.
The announcement, just a week after Pfizer first revealed promising preliminary results, comes as the company is preparing within days to formally ask U.S. regulators to allow emergency use of the vaccine.
Pfizer initially had estimated its vaccine, developed with German partner BioNTech, was more than 90% effective after 94 infections had been counted.
According to a statement by Pfizer, "the efficacy was consistent across age, gender, race and ethnicity demographic. The observed efficacy in adults over 65 years of age was over 94 per cent."
The findings follows the announcement by US biotech company Moderna, which had on Monday released preliminary data from late-stage clinical trials for its vaccine, which it said proved to be 94.5 per cent effective.
In a statement today, Pfizer and BioNTech said they expect to produce globally up to 50 million vaccine doses in 2020 and up to 1.3 billion doses by the end of 2021.