AstraZeneca Pauses Leading Vaccine Candidate Trial

AstraZeneca paused its Phase 3 COVID-19 vaccine trial, citing a suspected adverse reaction in one UK participant and an “abundance of caution.”

A standard review process triggered the hold, AstraZeneca said. It didn’t share details but noted the illness could be unrelated to the vaccine: Illnesses in large trials happen by chance “but must be independently reviewed to check this carefully.”

The pause in the trial of a front-runner vaccine candidate, developed with University of Oxford, is likely to slow the vaccine timeline, and potentially impact other clinical trials underway.

According to The Guardian, investigators will be examining the details of the illness and the person who contracted it to find out if there is a link. They will also look at the dose of vaccine they received, their state of general health and so on. They will hope this event can be explained and is not a risk to others. If so, the trial will soon resume. Researchers in other vaccine trials – there are nine now in phase 3, which is the last stage – will be looking to ensure they are not seeing a similar issue.

The disease is said to be transverse myelitis, although AstraZeneca has not confirmed that. That is inflammation of the sheath containing the nerves of the spinal cord. It can be treated by steroids to reduce the inflammation but the condition can be permanent, the report said.

Courtesy: Johns Hopkins Bloomberg School of Public Health