Human trials of the Oxford coronavirus vaccine are facing delays in the United States after a participant suffered a rare neurological condition, according to a leaked document.
The AstraZeneca report, seen by CNN, shows that the decision to pause the trials in early September was made after a previously healthy 37-year-old woman who had received two doses developed transverse myelitis, an inflammation of the spinal cord that can cause paralysis.
The unidentified UK-based volunteer was given the jabs in June and August but was hospitalised after she started to suffer “difficulty walking, pain and weakness in her arms and a headache after tripping while running in September”, the Daily Mail reports.
She is understood to have recovered fully.
The internal report by AstraZeneca, which owns the rights to the so-called AZD1222 vaccine, also reveals that the trials had been stopped before after another participant developed transverse myelitis.
“The first pause, in July, was not publicly revealed and the trial was restarted after it was determined the volunteer had multiple sclerosis, a condition that can cause the same neurological reaction,” says The Telegraph.
Following the latest hold-up, trials have resumed in the UK, Brazil, India and South Africa, but remain suspended in the US.
The “concerns around neurological side-effects” of vaccines are “especially sensitive in the US”, according to the newspaper, which notes that an emergency influenza vaccine issued in 1976 caused 450 cases, of which 30 were fatal, of Guillain-Barre syndrome, which also causes inflammation of the spinal cord.
The US Food and Drug Administration (FDA) and the National Institutes of Health (NIH) are reportedly “seeking to de-termine” what caused the case of transverse myelitis in the Covid trials before giving the green light for the testing to resume.