A late stage study of a coronavirus vaccine has been paused after a participant went down with a ‘mystery illness’.
Pharmaceutical company Johnson & Johnson, which is leading the study, says it is working to find out whether the illness is a coincidence or related to the jab.
The company said in a statement illnesses, accidents and other adverse events ‘are an expected part of any clinical study, especially large studies’, but that its physicians and a safety monitoring panel are investigating.
‘We have temporarily paused further dosing in all our Covid-19 vaccine candidate clinical trials,’ Johnson & Johnson said in a statement after health news website Stat first reported the news.
‘Following our guidelines, the participant’s illness is being reviewed and evaluated.
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‘We’re also learning more about this participant’s illness, and it’s important to have all the facts before we share additional information.’
Johnson & Johnson would not reveal any more details about the patient’s illness for privacy reasons.
The pause is at least the second to occur among several vaccines that have reached large-scale final tests in the US.
Temporary stoppages of large medical studies are relatively common. Few are made public in typical drug trials, but the coronavirus vaccine is being closely scrutinised due to the scale of the effort to find a viable jab.
Companies are required to investigate any serious or unexpected reaction that occurs during drug testing.
Because tests are conducted on tens of thousands of people, some medical problems are a coincidence.
One of the first steps the company said it would take would be to determine if the person received the vaccine or a placebo.
Final-stage testing of a vaccine made by AstraZeneca and Oxford University has been put on hold for the second time in the US, after a suspected adverse reaction to the injection.
The trial was stopped when a woman developed severe neurological symptoms consistent with transverse myelitis, a rare inflammation of the spinal cord. The trial restarted in the UK and some other countries shortly afterwards.
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