AstraZeneca Covid-19 vaccine study paused after illness reported
Late-stage studies of AstraZeneca’s Covid-19 vaccine candidate are on temporary hold while the company investigates if a report of a patient with a serious side effect is linked to the shot.
In a statement issued on Tuesday evening, the company said its “standard review process triggered a pause to vaccination to allow review of safety data”.
AstraZeneca did not reveal any information about the possible side effect except to call it “a potentially unexplained illness”.
The news site Stat first reported the pause in testing, saying the possible side effect occurred in the United Kingdom.
An AstraZeneca spokesperson confirmed the pause in vaccinations covers studies in the US and other countries.
British Health Secretary Matt Hancock said he is not too concerned.
The Health Secretary told LBC: “This is a normal part of a vaccine development that, when you find a problem, the system is paused while you investigate that particular problem.
“What it underlines is that we won’t bring forward a vaccine unless it is safe, no matter how enthusiastic I am for a vaccine.”
He added: “The good news is that we have on order many different vaccines – 340 million doses in total, which is far more than we need for the UK population, so that if one doesn’t come off then we have other irons in the fire.
“This is a pause not a stop so I am hopeful (AstraZeneca) will be able to resume but only if it is safe to do so.”
Late last month, AstraZeneca began recruiting 30,000 people in the US for its largest study of the vaccine.
It also is testing the vaccine, developed by Oxford University, in thousands of people in Britain, and in smaller studies in Brazil and South Africa.
Two other vaccines are in huge, final-stage tests in the United States, one made by Moderna Inc and the other by Pfizer and Germany’s BioNTech.
Those two vaccines work differently than AstraZeneca’s, and the studies already have recruited about two-thirds of the needed volunteers.
Temporary holds of large medical studies are not unusual, and investigating any serious or unexpected reaction is a mandatory part of safety testing.
AstraZeneca pointed out that it is possible the problem could be a coincidence; illnesses of all sorts could arise in studies of thousands of people.
“We are working to expedite the review of the single event to minimise any potential impact on the trial timeline,” the company statement said.
The development came the same day that AstraZeneca and eight other drugmakers issued an unusual pledge, vowing to uphold the highest ethical and scientific standards in developing their vaccines.
The announcement follows worries that President Donald Trump will pressure the US Food and Drug Administration to approve a vaccine before it is proven to be safe and effective.
The US has invested billions of dollars in efforts to quickly develop multiple vaccines against Covid-19.
But public fears that a vaccine is unsafe or ineffective could be disastrous, derailing the effort to vaccinate millions of Americans.
Representatives for the FDA did not immediately respond to requests for comment Tuesday evening.