LONDON – A woman who received an experimental coronavirus vaccine developed severe neurological symptoms that prompted a pause in testing, a spokesman for drugmaker AstraZeneca said Thursday.
The study participant in late-stage testing reported symptoms consistent with transverse myelitis, a rare inflammation of the spinal cord, said company spokesman Matthew Kent.
The study was previously stopped in July for several days after a participant who got the vaccine developed neurological symptoms; it turned out to be an undiagnosed case of multiple sclerosis that was unrelated to the vaccine.
It also is testing the vaccine in thousands of people in Britain, and in smaller studies in Brazil and South Africa.
Temporary holds of large medical studies aren’t unusual, and investigating any serious or unexpected reaction is a mandatory part of safety testing.