U.S. health officials say AstraZeneca may have skewed vaccine 'efficacy data' with 'outdated information'


In an unusual statement issued after midnight on Tuesday, the National Institute of Allergy and Infectious Diseases said an independent monitoring board overseeing AstraZeneca's U.S. COVID-19 vaccine trial told the NIAID and the drugmaker late Monday "it was concerned by information released by AstraZeneca on initial data from its COVID-19 vaccine clinical trial." The NIAID, a unit of the National Institutes of Health, is led by Dr. Anthony Fauci, President Biden's top medical adviser.
AstraZeneca reported early Monday that its vaccine had proved to be 79 percent effective against symptomatic COVID-19 in a large U.S. trial, 100 percent effective against serious illness or hospitalization, and carried no increased risk of blood clots. The results were seen as a shot in the arm for the beleaguered vaccine.
But the Data and Safety Monitoring Board (DSMB) "expressed concern that AstraZeneca may have included outdated information from that trial, which may have provided an incomplete view of the efficacy data," the NIAID said. The Food and Drug Administration and Centers for Disease Control and Prevention will ultimately conduct a thorough review of the data before approving AstraZeneca's vaccine for use in the U.S., the agency said, but AstraZeneca should "work with the DSMB to review the efficacy data and ensure the most accurate, up-to-date efficacy data be made public as quickly as possible."
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The DSMB's analysis of AstraZeneca's U.S.-based trial was "delayed several times because the board had to ask AstraZeneca for revised reports from those handling trial data on behalf of the company," The New York Times reports, citing a person familiar with the matter.
Friction between a safety monitoring board and a study sponsor is "highly irregular," and the NIAID's post-midnight statement is "so, so troubling," clinical trials expert Dr. Eric Topol told the Times. "I've never seen anything like this." AstraZeneca had yet to respond to the statement early Tuesday.
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Peter has worked as a news and culture writer and editor at The Week since the site's launch in 2008. He covers politics, world affairs, religion and cultural currents. His journalism career began as a copy editor at a financial newswire and has included editorial positions at The New York Times Magazine, Facts on File, and Oregon State University.
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