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US Health Officials Raise Flags About AstraZeneca COVID-19 Vaccine Trial Data

TUESDAY, March 23, 2021 -- U.S. health officials called the results of the AstraZeneca COVID-19 vaccine trial into question early Tuesday, saying the company may have used outdated data that could have changed its conclusion about the efficacy of the vaccine.

On Monday morning, AstraZeneca had announced that its vaccine was 79 percent effective in protecting against COVID-19 infection in the large U.S. clinical trial. But in a statement released shortly after midnight on Monday, the National Institute of Allergy and Infectious Diseases (NIAID) said the Data and Safety Monitoring Board, a panel of medical experts under the National Institutes of Health that has been overseeing the U.S. AstraZeneca trial, had notified government agencies and AstraZeneca late Monday that it was "concerned" by information the company had released. The monitoring board said the company may have relied on "outdated information" that "may have provided an incomplete view of the efficacy data," the NIAID statement said.

NIAID urged AstraZeneca to work with the monitoring board "to review the efficacy data and ensure the most accurate, up-to-date efficacy data be made public as quickly as possible."

The relationship between AstraZeneca and U.S. authorities has been tense since last year, when senior health officials believed the company was not being forthright about the design of its clinical trials, its results, and safety issues, The New York Times reported. That U.S. trial, which involved more than 32,000 participants, was the largest test of its kind for the shot. The company has said it will provide the U.S. Food and Drug Administration with a more comprehensive, recent set of data than what it disclosed on Monday.

The company's efforts might not make much difference in the United States, where the vaccine is not yet authorized and is unlikely to become available before May, The Times said. By then, there will be enough vaccine doses for all of the nation's adults from the three vaccines that have already been authorized: Pfizer, Moderna, and Johnson & Johnson.

The New York Times Article

NIAID Statement

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