Pharmaceutical company AstraZeneca, in a new analysis on Thursday, said that its coronavirus vaccine showed 76% efficacy. The study came two days after United States’ medical body National Institute for Allergy and Infectious Diseases flagged the possibility that the company may have released outdated information in the initial data of its vaccine trial.
The NIAID statement was based on the data furnished by AstraZeneca, in the advanced trial study of its vaccine released on Monday. In that study, AstraZeneca had pegged the vaccine’s efficacy at 79%. NIAID, however, had asked AstraZeneca to review the efficacy data provided by it and “ensure the most accurate, up-to-date efficacy data be made public as quickly as possible”.
The American medical body had said that the Data and Safety Monitoring Board had expressed concern about the matter and also raised it with the Biomedical Advanced Research and Development Authority and AstraZeneca.
Besides the minor downward revision in the updated study released on Thursday, AstraZeneca reiterated its earlier claim that the vaccine was 100% effective against cases of severe or critical disease and hospitalisation. In case of symptomatic patients above the age of 65, who took part in the trial, the company revised the vaccine’s efficacy to 85%, from the earlier stated 80%.
“These results have been presented to the independent Data Safety Monitoring Board,” AstraZeneca said in the statement.
The company said that following the release of the updated study, it was looking to apply for authorisation of use in the US.
“The primary analysis is consistent with our previously released interim analysis, and confirms that our Covid-19 vaccine is highly effective in adults, including those aged 65 years and over,” Mene Pangalos, Executive Vice President, BioPharmaceuticals R&D, a research and development unit at AstraZeneca, said. “We look forward to filing our regulatory submission for Emergency Use Authorization in the US and preparing for the rollout of millions of doses across America.”
The company will submit the primary analysis for peer-reviewed publication in the coming weeks.
The latest data was based on 190 infections among more than 32,400 participants in the United States, Chile and Peru. The earlier interim data was based on 141 infections through February 17, according to Reuters.
The revision to the efficacy rate will go a long way to putting the vaccine back on track for gaining US emergency use authorisation, experts quoted by Reuters said.
“The vaccine efficacy against severe disease, including death, puts the AZ [AstraZeneca] vaccine in the same ballpark as the other vaccines,” said William Schaffner, an infectious disease expert from the Vanderbilt University School of Medicine, adding that he expects the shot to gain US approval.