AstraZeneca's COVID-19 vaccine adverse event has NIH 'very concerned'

Pascal Soriot
AstraZeneca CEO Pascal Soriot (AstraZeneca)

Leaders at the National Institutes of Health (NIH) are “very concerned” about the adverse event that led AstraZeneca to pause its COVID-19 vaccine clinical trial, according to the intramural clinical director at one of its divisions.

Talking to KHN, the National Institute for Neurological Disorders and Stroke’s Avindra Nath said “the highest levels of NIH are very concerned.” The comment comes amid a divergent global regulatory response to the adverse event. While the U.K. regulator has cleared the trial to resume, the FDA is still assessing the situation, and the NIH has begun an investigation into the case. 

The divergence may reflect differences in access to information and materials on either side of the Atlantic. Nath said the NIH is yet to access tissue or blood samples from the patient, who was part of the U.K. portion of the AZD1222 development program. 

AstraZeneca began the U.S. portion of the program shortly before putting the clinical trial on hold in response to an adverse event, which Nath and others have identified as a case of transverse myelitis. It is unclear how long it will take the FDA to gather the information it needs to decide whether to clear AstraZeneca to restart the study.

Some observers think AstraZeneca could be doing more to help U.S. authorities assess the situation. Nath called for the company “to be more forthcoming,” adding that “we would like to see how we can help, but the lack of information makes it difficult to do so.”

Jesse Goodman, M.D., the FDA’s lead vaccine regulator during the Obama era, also criticized the lack of information, arguing that it is currently impossible to understand what the diagnosis was or why the safety monitoring board had the confidence to support the resumption of dosing. AstraZeneca has cited patient privacy to explain the secrecy, but that has failed to quell the calls for information. 

“I think it would be really helpful to know what their assessment of these issues was,” Goodman said. “What was the diagnosis? If there wasn’t a clear diagnosis, what is it that led them to feel the trial could be restarted? There is so much interest and potential concern about a COVID-19 vaccine that the more information that can be provided, the more reassuring that would be.”

AstraZeneca said investigators and participants “will be updated with the relevant information and this will be disclosed on global clinical registries.”