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# AstraZeneca Vaccine Safety Info Slow Coming to FDA: Report
- URL: https://www.fdaweb.com/astrazeneca-vaccine-safety-info-slow-coming-to-fda-report/
- Published: 2020-10-15T12:00:00.000Z
- Updated: 2026-09-14T16:32:38.000Z
- Author: David McFarland
- Tags: Biologics, #legacy-id-D5147881

CNN says a source familiar with the AstraZeneca Covid-19 vaccine trial told the network that the company took until last week to get adverse event safety information to FDA, which placed a 9/9 clinical hold on the vaccine trial after a participant became ill with a neurological condition. The CNN [report](https://www.cnn.com/2020/10/14/health/astrazeneca-covid-vaccine-trial/index.html?ref=fdaweb.com) says the source indicated the delay came because the trial participant was in the UK and the European Medicines Agency collects information in a different format than that used by FDA. “They had to convert data from one format to another format,” the source said. “They had to spend a lot of hours to get what they wanted.” The trial has resumed in the UK, while FDA continues to consider whether to permit resumption in the U.S.

Former FDA commissioner **Robert Califf** told CNN he doubted that technology was the reason for the delayed submission. He said he believes that FDA is being very careful and is looking for additional information about the participant whose adverse event led to the current pause and also about the illness of a participant that caused a pause in July.

“FDA may be asking for specialized tests or some kind of further follow-up,” Califf said. “And it’s not just a matter of raw data. They want to hear expert opinions and aggregate all this and that can take some time.” He also said there could be differences of opinion within AZ or FDA about what exactly happened to the trial participants and whether the vaccine is to blame. “There’s a lot of judgment involved in these decisions,” he said.

Without referring to a specific situation, FDA commissioner **Stephen Hahn** told *Bloomberg News* that FDA wants to do a thorough assessment of safety events. “We have a give-and-take with companies,” he said. “Sometimes that takes a short period of time and sometimes that takes longer.”

The source who gave information to CNN agreed with Califf that FDA is going to be very methodical in reviewing the data. “I’m sure FDA wants to make their decision as soon as they can, but they also need to make sure that decision is sound,” the source said. “And it’s critical that the American public has trust in FDA. If we lose trust in FDA, we’re done.”