The ‘adverse reaction’ in a participant of the Oxford University AstraZeneca coronavirus vaccine trial has been revealed.
Following the participant’s symptoms, the vaccine’s clinical trial, currently in its third phase, was put on hold on Wednesday.
During a conference call, the pharmaceutical company’s chief executive Pascal Soriot told investors the participant was a woman from the UK, health site STAT reports.
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She had experienced neurological symptoms consistent with transverse myelitis - a rare and serious spinal inflammatory disorder that can cause muscle weakness and paralysis.
Her diagnosis was not yet confirmed but her condition is improving and she’s expected to be discharged from hospital.
Soriot also confirmed the woman had in fact been injected with the company’s COVID-19 vaccine and not a placebo.
He also revealed it wasn’t the first time the trial had been halted.
In July, a participant had experienced neurological symptoms and was later diagnosed with multiple sclerosis.
The diagnosis was deemed unrelated to the vaccine, he said.
Australia’s Health Minister Greg Hunt says the illness in the UK woman “is undiagnosed in terms of its specific form and nor is the source known”.
Hunt says the setback will not affect the vaccine’s scheduled delivery in Australia.
“(AstraZeneca) have no belief that it will be changed in terms of its nature, form or delivery, but they are always subject to the medical advice,” he said.
On Wednesday, Hunt said the halt in the trial demonstrated the “rigour and high standards of the clinical trial process”.
“A COVID-19 vaccine will not be made available in Australia until it passes the strict safety and efficacious regulatory assessments by the TGA,” he said in a statement.
Up to 50,000 people across the UK, US, Brazil and South Africa are participating in Phase III of the Oxford University vaccine trial.
Earlier this week, the federal government announced it had secured 34 million doses of the AstraZeneca drug to be distributed next year, if the trials prove successful.
It has also struck a separate deal for a drug being developed at the University of Queensland, which is in much earlier stages of testing.
- With AAP