AstraZeneca has recently announced that it had resumed phase three trials in the UK, after receiving confirmation from the UK Medicines Health Regulatory Authority that it was safe to do so. The company said in a blog post it could not reveal any medical information, saying only that the standard review process triggered a voluntary pause, adding it was working with health authorities in other countries to determine when other clinical trials may resume.
The trials were paused earlier this week after a participant experienced serious neurological symptoms.
The hold was first reported by STAT, which later found that the halt was triggered when a patient in the United Kingdom was hospitalized with severe neurological symptoms. The symptoms were apparently similar to those found in people with transverse myelitis, a kind of inflammation of the spinal cord. The patient who is expected to recover apparently got the vaccine as part of the trial, but that doesn’t mean the vaccine caused the illness.
During a call with investors, AstraZeneca head Pascal Soriot said that this was actually the second clinical hold on the trial, according to STAT. The first pause was reportedly caused by a different person who came down with neurological symptoms — but in that case, they were diagnosed with multiple sclerosis, something unrelated to the vaccine.
To figure out what happened in this new case, researchers will have to dig into the data, a process that could take some time. In the meantime, other trials are looking for evidence of similar symptoms that might have cropped up during their tests.