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AstraZeneca resumes coronavirus vaccine clinical trials, but only in the UK

AstraZeneca resumes coronavirus vaccine clinical trials, but only in the UK


Antivirus: a weekly newsletter of coronavirus research

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An AstraZeneca logo on a building
AstraZeneca is partnering with the University of Oxford to develop and test a COVID-19 vaccine.
Photo by Paul Ellis / AFP via Getty Images

A big vaccine trial halted this week after a participant experienced serious neurological symptoms. It was one of the first known bumps in the road for the highly touted vaccine candidate, which is being developed by AstraZeneca and the University of Oxford. 

AstraZeneca said Saturday it had resumed phase three trials in the UK only, 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.

Hitting pause on a promising vaccine candidate may be jarring, especially during a deadly pandemic. But it’s not unexpected, and it’s exactly the kind of thing that large-scale clinical trials are for. In clinical trials, researchers carefully monitor patients for any kind of bad reactions to the drug or treatment. If something goes wrong, they can pause, investigate, and then keep going once it’s safe to do so. 

“You take any group of 30,000 people, and you watch them over the course of two or three months, it’s likely somebody is going to have an illness that you didn’t expect,” Francis Collins, head of the National Institutes of Health, told NBC. “And until you’re sure that it was not connected to the trial, and you need to put it on clinical hold.”

“It’s likely somebody is going to have an illness that you didn’t expect”

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. 

We can’t skip steps of the research process if we want to end up with a safe and effective vaccine

Again, this is normal. We can’t skip steps of the research process if we want to end up with a safe and effective vaccine. It’s also a pretty common, even for trials that have already made it through multiple, smaller rounds of testing. 

But you don’t have to take my word for it. Back in 2017, the Food and Drug Administration came out with a report that picked out 22 different case studies showing when a promising drug, treatment, or vaccine candidate just didn’t make that final cut. In 14 cases, the therapies weren’t effective. In one, it was unsafe. And in seven cases, they were both unsafe and not effective. These were all devices, drugs, and vaccines that had done great in the lab, and some were even approved to treat other conditions. But the human body is complex. And as the FDA report notes, this sample of failed tests shows “how logical presumptions without corroborating clinical evidence can be unreliable.”

In developing a vaccine to fight this pandemic, we’ll need to avoid past presumptions and pitfalls, and focus on the evidence — even if that means taking a moment to stop and wait for the science to catch up. 

Here’s what else happened this week.


New Research Shows Disproportionate Rate of Coronavirus Deaths in Polluted Areas
A new peer-reviewed study by both ProPublica and SUNY found that there were more coronavirus-related deaths in areas with high industrial air pollution.
(Lylla Younes and Sara Sneath / ProPublica)

The Sturgis Biker Rally Did Not Cause 266,796 Cases of COVID-19
This is a good analysis of a study modeling virus transmission that got a ton of attention this week. It digs into exactly why the attention-grabbing numbers from the study are worth a skeptical look.
(Jennifer Beam Dowd / Slate)

As states lift restaurant restrictions, CDC report links dining out to increased COVID-19 risk
People who tested positive for the coronavirus were more likely to have gone out to eat than people who didn’t, according to a new report from the Centers for Disease Control and Prevention. The study surveyed 314 people across several states and did not distinguish between indoor or outdoor dining.
(Erika Edwards / NBC News)


A third of Americans might refuse a Covid-19 vaccine. How screwed are we?
Once we get a COVID-19 vaccine, it will only help curb the spread of disease if people actually take it. Right now, people in the US are skeptical.
(Brian Resnick / Vox)

Pharmaceutical companies sign vaccine safety pledge
People’s skepticism of the vaccine development and approval process prompted several companies to sign a pledge promising to put safety first.
(Mary Beth Griggs / The Verge)

China Injects Hundreds of Thousands With Experimental Covid-19 Vaccines
Meanwhile, in China, hundreds of thousands of people received experimental vaccines, according to a new report in The Wall Street Journal. These vaccines have not yet completed phase three trials.
(Chao Deng / The Wall Street Journal)

8,000 jumbo jets needed to deliver coronavirus vaccines globally, IATA warns
After a vaccine gets developed, it has to get from production facilities to population centers. That’s going to require a lot of logistical power, including air power. To illustrate the challenge, a trade group calculated the amount of cargo space that would be required to transport a single-dose vaccine to 7.8 billion people. They came up with 8,000 jets. A few important notes: this is all hypothetical, it’s still early days, and vaccines could potentially travel by land or sea, too.
(Holly Ellyatt / CNBC)


How Many 9/11 Survivors Have Died of COVID-19? At Least 42 — and Likely Many More
Yesterday, on the 19th anniversary of the 9/11 attacks, a nonprofit news organization called The City reported on the dozens of people who survived the 9/11 attacks, only to die of COVID-19. More than 1,300 survivors contracted the disease.

This story is part of “Missing Them,” an effort by The City to recognize and remember every person in New York City who died of COVID-19.
(Ashley Rodriguez and Beatriz Muylaert / The City)

More than numbers 

To the more than 28,287,928 people worldwide who have tested positive, may your road to recovery be smooth.

To the families and friends of the 911,591 people who have died worldwide — 192,616 of those in the US — your loved ones are not forgotten.

Thanks for joining us this week, and stay safe, everyone.

Update September 12th, 10:12AM ET: Adds that AstraZeneca has resumed clinical trials of its vaccine in the UK