The University of Oxford and AstraZeneca Plc have re-launched a UK trial of an investigational COVID-19 vaccine after it was halted due to concerns over a participant who fell ill.
The UK Medicines Health Regulatory Authority recommended resuming trials after an independent review of safety data triggered a hiatus on September 6, Oxford said in a statement. He declined to disclose details of the volunteer’s illness.
While temporary shutdowns are common in vaccine trials, the shutdown of the closely watched Astra-Oxford study had raised concerns about the viability of one of the fastest-growing experimental designs seeking to protect against the pandemic . The race to develop a COVID-19 vaccine has compressed what is normally a decade-long process into months, with data from end-stage trials expected as early as next month.
Statements from Astra and Oxford on Saturday said nothing about the state of testing outside the UK. Trials of the Oxford vaccine were underway in the United States, Brazil, South Africa and India before being suspended after the safety review.
A representative from the U.S. National Institutes of Health could not be reached immediately for comment. A spokesperson for AstraZeneca declined to comment.
AstraZeneca CEO Pascal Soriot said on Thursday the vaccine could still be available by the end of the year. An independent safety committee was examining whether the participant’s illness was caused by the vaccine or was unrelated, he said.
Soriot said it was not clear whether the participant had a condition called transverse myelitis, a suspected diagnosis. NIH Director Francis Collins told a Senate committee on Wednesday that the trial was suspended due to a “spinal cord problem.”
“We cannot disclose medical information about the disease for reasons of participant privacy,” Oxford said. “We are committed to ensuring the safety of our participants and to the highest standards of conduct in our studies and will continue to closely monitor safety.”
Oxford said about 18,000 people received “study vaccines” as part of the trials. It had started a large phase 3 trial in the United States at the end of August, with the aim of recruiting 30,000 people.
AstraZeneca is one of many companies participating in the US government’s Operation Warp Speed program to accelerate the deployment of a coronavirus vaccine. In May, the company signed a $ 1.2 billion agreement with the United States to support clinical studies and provide 300 million doses of the vaccine. It has pledged to provide the vaccine on a not-for-profit basis during the pandemic and has made deals around the world to provide nearly 3 billion doses.
Oxford began human trials of its shot on April 23 on nearly 1,100 volunteers and by the end of May moved quickly to a large-scale UK study involving more than 10,000 people over the age of 55 . number of COVID-19 cases in the control group compared to the vaccinated group to show that the vaccine is effective.
The trial began just as infection rates in the UK began to drop in May, making it more difficult to demonstrate the vaccine’s effectiveness. In recent weeks, new cases have increased again.
In July, Oxford reported the first results showing the vaccine increased levels of protective neutralizing antibodies and immune T cells that target and destroy infected cells. He did not report any serious adverse events in his Phase 1-2 trial. Researchers continued to try a two-dose regimen after finding that it produced a stronger response in 10 volunteers. It is not known whether the participant who became ill had two or one doses.