Home — Health AstraZeneca used ‘outdated and potentially misleading data’ that overstated the effectiveness of its vaccine, independent panel says

AstraZeneca used ‘outdated and potentially misleading data’ that overstated the effectiveness of its vaccine, independent panel says

by Mary Sewell

In a memo sent to the company and government officials, obtained by The Washington Post, experts who have been overseeing the vaccine trial expressed concern and disappointment that the drugmaker had presented “outdated and potentially misleading” data on its coronavirus vaccine, making the shots appear more effective than shown by fuller data.


On Monday, AstraZeneca and academic scientists trumpeted a vaccine that was 79 percent effective in its large U.S. clinical trial. That news release triggered concern among independent monitors who had seen more recent data because when an additional month was taken into account, the effectiveness ranged from 69 to 75 percent. The letter came from 11 leading statisticians, infectious-disease physicians, and ethics experts appointed by the National Institutes of Health to review trial data for all the major coronavirus vaccines supported by the federal government. It says the company’s decision to use early data that put the vaccine in the most favorable light is a scientific misstep that could erode trust in the shot.

The letter, sent late Monday, opens a rare window into the typically personal interactions between a company and the Data and Safety Monitoring Board that polices patient safety and the scientific validity of clinical trials. These monitors aren’t distant observers or whistleblowers; they are independent experts granted inside access to the AstraZeneca results for months, seeing the complete data before even the company has access.

“The DSMB is concerned that AstraZeneca chose to use data that was already outdated and potentially misleading in their press release,” the letter states. The data “they chose to release was the most favorable for the study instead of the most recent and most complete. Decisions like this are what erode public trust in the scientific process. This turmoil might be seen as a technical issue in other circumstances because the additional data doesn’t appear to overturn the fundamental finding that the vaccine works. AstraZeneca released a statement Tuesday promising that the complete analysis of its data would be available within 48 hours and indicated the results would be consistent with the study released Monday.

You may also like

Leave a Comment