Sept. 9 (UPI) -- Pharmaceutical giant AstraZeneca said it has paused global trials of its COVID-19 vaccine candidate after it caused an unexplained illness in one of its volunteers.
The Britain-based drug company said the pause of randomized, controlled trials of its coronavirus vaccine candidate developed with Oxford University was led by a standard review process to allow an independent committee to look over safety data.
"This is a routine action, which has to happen whenever there is a potentially unexplained illness in one of the trials," an AstraZeneca spokesman said in a statement emailed to UPI.
Illnesses during large trials "will happen," the company said, adding that they must undergo a careful and independent review, a process the drugmaker is working to expedite to minimize any potential impact on the trial's projected timeline.
"We are committed to the safety of our participants and the highest standards of conduct in our trials," the spokesman said.
Matt Hancock, Britain's health secretary, told Sky News on Wednesday that the pause isn't a cause for concern and shouldn't yet be considered a setback.
"It depends on what they find when they do the investigation," he said. "There was a pause earlier in the summer and that was resolved without a problem."
The pause came a week after the multinational said it started Phase III clinical trials in the United States of its AZD1222 candidate.
The trial consists of participants receiving two doses of either the vaccine or a placebo saline control separated by four weeks.
Some 30,000 adults in the United States were to be recruited for the trial, increasing its total volunteers to some 50,000 globally.
On Tuesday, AstraZeneca and eight other drugmakers pledged to "uphold the integrity of the scientific process" amid pressure to produce a vaccine quickly.
The World Health Organization has repeatedly warned against so-called vaccine nationalism, saying that authorizing a vaccine prematurely could hamper research and introduce a drug to the public that not only doesn't prevent COVID-19 but could be unsafe.
AstraZeneca is one of several companies developing potential COVID-19 vaccines. Click here for our COVID-19 vaccine tracker.