AstraZeneca Plc, the U.K. drugmaker developing a Covid-19 vaccine with the University of Oxford, has been cleared by U.S. regulators to restart a trial halted in the country for more than a month on concerns about a volunteer who became ill.
The U.S. Food and Drug Administration authorized the trial to resume Friday, according to statements from AstraZeneca and Oxford. The FDA reviewed data from global studies and decided it was safe to begin testing again, the partners said.
The decision removes a significant impediment for the partners trying to get their coronavirus shot across the line. They are among the front-runners in the global quest for a vaccine, along with developers such as Pfizer Inc. and Moderna Inc. Astra’s U.S. trial will test the shot on 30,000 volunteers, taking the total number of participants in advanced trials for the jab to 50,000, according to Oxford.
“We should be reassured by the care taken by independent regulators to protect the public and ensure the vaccine is safe before it is approved for use,” Pascal Soriot, the drugmaker’s chief executive officer, said in a statement. This “allows us to continue our efforts to develop this vaccine to help defeat this terrible pandemic.”
A representative for the FDA didn’t immediately respond to a request for comment.
Trials of the Astra-Oxford vaccine resumed weeks ago outside the U.S., in countries including the U.K., South Africa and Brazil. Symptoms that prompted the partners to pause the studies were unlikely to be linked to the shot, or there was insufficient evidence to say for sure, according to documents sent to participants. The safety reviews began after volunteers developed unexplained neurological symptoms including limb weakness or “changed sensation,” a document posted by Oxford shows.
Tests to decide whether experimental Covid-19 shots are safe and effective are progressing at an unprecedented speed as drugmakers and governments look for a way out of the crisis. The virus has continued to advance, killing more than 1.1 million people worldwide.
Results from the late-stage trials of the Astra-Oxford shot are expected later this year, and will depend on local rates of infection where the studies are taking place, according to Astra.
The British pharmaceutical company faced a flurry of headlines this week when it emerged that a participant in the Brazil vaccine trial had died. It was quickly determined the volunteer was in the control arm of the study and hadn’t received the shot. Brazil’s health authority said an international committee had reviewed the event and the trial would continue.
Another vaccine maker, Johnson & Johnson, said in mid-October that it would pause its trial to investigate an illness in a study participant. Operation Warp Speed head Moncef Slaoui said in an interview earlier this week that both the Astra and J&J trials could resume in the coming days.
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