Pfizer Inc and BioNTech SE on Monday said their vaccine candidate was found to be more than 90 per cent effective in preventing COVID-19.
"Today is a great day for science and humanity. The first set of results from our Phase 3 COVID-19 vaccine trial provides the initial evidence of our vaccine's ability to prevent COVID-19," Pfizer Chairman and Chief Executive Officer Albert Bourla said.
"We are reaching this critical milestone in our vaccine development program at a time when the world needs it most with infection rates setting new records, hospitals nearing over-capacity and economies struggling to reopen," he added.
After discussion with the Food and Drug Administration (FDA), the companies recently elected to drop the 32-case interim analysis and conduct the first interim analysis at a minimum of 62 cases, the statement said.
"... we are a significant step closer to providing people around the world with a much-needed breakthrough to help bring an end to this global health crisis. We look forward to sharing additional efficacy and safety data generated from thousands of participants in the coming weeks," Bourla said.
However, the announcement does not mean a vaccine is imminent.
This interim analysis, from an independent data monitoring board, looked at 94 infections recorded so far in a study that has enrolled nearly 44,000 people in the US and five other countries, the AP reported.
Pfizer Inc did not provide any more details about those cases, and cautioned the initial protection rate might change by the time the study ends.
The shots made by Pfizer and its German partner BioNTech are among 10 possible vaccine candidates in late-stage testing around the world -- four of them so far in huge studies in the US.
Another US company, Moderna Inc, also has said it hopes to be able to file an application with the Food and Drug Administration later this month.
BioNTech co-founder and CEO Ugur Sahin said: 'The first interim analysis of our global Phase 3 study provides evidence that a vaccine may effectively prevent COVID-19. This is a victory for innovation, science and a global collaborative effort.'
'Especially today, while we are all in the midst of a second wave and many of us in lockdown, we appreciate even more how important this milestone is on our path towards ending this pandemic and for all of us to regain a sense of normality,' he added.
The Phase 3 clinical trial of BNT162b2 began on July 27 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, the statement said.
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 study also will evaluate the potential for the vaccine candidate to provide protection against COVID-19 in those who have had prior exposure to SARS-CoV-2, as well as vaccine prevention against severe COVID-19 disease, it added.
'Pfizer and BioNTech are continuing to accumulate safety data and currently estimate that a median of two months of safety data following the second (and final) dose of the vaccine candidate - the amount of safety data specified by the FDA in its guidance for potential Emergency Use Authorization - will be available by the third week of November,' the statement said.
Based on current projections, the companies expect to produce globally up to 50 million vaccine doses in 2020 and up to 1.3 billion doses in 2021, it added.
The companies also plan to submit data from the full Phase 3 trial for scientific peer-review publication, the statement said.
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