AstraZeneca COVID-19 vaccine trial suspended in US for at least several more days amid concerns over serious complication

• The late-stage clinical trial for AstraZeneca’s COVID-19 vaccine will be suspended in the US for at least several more days, Reuters reported Monday, citing a source familiar with the matter.
• The trial was suspended last week after a volunteer developed transverse myelitis, an inflammatory syndrome that affects the spinal cord.
• It is not known whether the condition was caused by the experimental vaccine.
• Oxford University, AstraZeneca’s partner on the vaccine, has already resumed its trial in Britain.
• But in the US, experts at the National Institutes of Health are “very concerned” about the potential complication from the vaccine, Kaiser Health News reported Monday.
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The US clinical trial of AstraZeneca’s COVID-19 vaccine will be suspended for the next several days as the US Food and Drug Administration investigates a potential side effect, according to Reuters.

Sources told the news agency on Monday that enrollment in the trial was not being reopened “until at least midweek,” pending the investigation.

The FDA did not immediately respond to a request for comment.

The British-Swedish pharmaceutical company’s clinical trial was suspended last week after one volunteer was hospitalized and reportedly diagnosed with transverse myelitis, which causes inflammation in the spinal cord and is associated with viral infections.

Oxford University, AstraZeneca’s partner on the vaccine, has already resumed its clinical trial in Britain, saying in a statement that adverse reactions were an “expected” part of a large trial, the BBC reported. The late-stage trial involves around 30,000 participants in the US, UK, Brazil, and South Africa.

In the US, regulators are more hesitant to resume the trial, with the government-funded National Institutes of Health having now launched an investigation of its own, Kaiser Health News reported Monday.

“The highest levels of NIH are very concerned,” Dr. Avindra Nath, leader of viral research at NIH’s Institute for Neurological Disorders and Stroke, told the news outlet. “The last thing you want to do is hurt healthy people.”

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