Independent panel questions AstraZeneca's positive US vaccine study data

Just hours after AstraZeneca's US chief appeared on FOX News Monday touting the positive results of the company's COVID-19 US clinical trial, an independent safety review board said the company may have chosen to use "outdated and potentially misleading" data to make its vaccine appear more effective that it was.

The pharmaceutical company announced in a press release Monday its AstraZeneca-Oxford University vaccine was 79% effective at preventing symptomatic disease and 100% effective at preventing severe COVID-19.

Hours after the company’s announcement, the Data and Safety Monitoring Board (DSMB), an independent panel of experts which reviews study data before pharmaceutical companies and regulators see it, sent a letter to the National Institute of Allergy and Infectious Disease claiming AstraZeneca based its findings on more favorable data rather than more complete and current data.

In a copy of the letter obtained by the Washington Post, the DSMB wrote that it had been meeting with AstraZeneca in February and March and had seen data the vaccine may be 69% to 74% effective, lower than the 79% efficacy the company claimed it its press release Monday.

Dr. Benjamin Neuman, Ph.D., the chief virologist at Texas A&M University-Texarkana, says the AstraZeneca-Oxford vaccine trials were conducted in multiple countries.

"The question is, is it just that it doesn't include the most recent European data, or are they using some of those older studies and not others for particular reasons," Neuman says. "It may be a case where they just need to explain what's going on."

In a written statement, AstraZeneca said the findings it announced were based on a pre-specified interim analysis that had a February 17th cut-off date for data.

The company said it would immediately engage with the DSMB to discuss its most up-to-date data and would reissue its updated results within 48 hours.

This comes as vaccinations in Europe are resuming after several countries paused the use of the AstraZeneca vaccine to investigate about 25 cases of extremely rare blood clotting complications in AstraZeneca vaccine recipients.

The European Medicines Agency, the regulatory body that oversees vaccines, reviewed the cases and found the AstraZeneca-Oxford vaccine was safe and effective.  The EMA said although there appeared to be no causal link between the vaccine and the clotting problems, it could not rule out a potential link to the rare blood clots.

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