AstraZeneca halts COVID-19 vaccine trial after 'unexplained illness'

Friday, 11 Sep, 2020

140 candidate vaccines are under development across the world, 30 of which have entered the clinical trial phase.

Now as for transverse myelitis, it can be serious.

Dr. Barker and Dr. Raveendran said more details were needed on the pause of the trial to draw any firm conclusions.

AstraZeneca's vaccine, known as AZD1222, uses an adenovirus that carries a gene for one of the proteins in SARS-CoV-2, the virus that causes COVID-19. "So, this ought to be reassuring to everybody listening that when we say we are going to focus first on safety and make no comprises, here is Exhibit A about how that is happening in practice".

FRANCIS COLLINS: This certainly happens in any large-scale trial where you have tens of thousands of people invested in taking part, and some of them may get ill.

Hours after AstraZeneca suspended the final testing of its potential Covid-19 vaccine because of a volunteer's unexplained illness, America's top medical experts at the forefront of the White House coronavirus task force promised lawmakers they are ready to roll up their sleeves and take the Covid-19 vaccine as soon as it is declared safe. The posting said the cause was being investigated.

"It's really one of the safety valves that you have on clinical trials such as this, so it's unfortunate that it happened", Fauci said.

Outside experts, serving on an independent data and safety monitoring board that oversees the trial, will try to determine whether the condition was caused by the vaccine, or was unrelated. And so far, AstraZeneca hasn't revealed much information - they're only saying that one of their volunteers has a "potentially unexplained illness".

The vaccine trial had been due to conclude in November but Dr Barker and Dr Raveendran said this pause would likely delay that timeline.

The company voluntarily suspended the study yesterday after one participant in the United Kingdom experienced a serious adverse reaction, a rare inflammatory condition affecting the spinal cord called transverse myelitis that is caused by infections or immune system disorders.

"He stated that there is no final diagnosis and that there will not be one until more tests are carried out".

"I don't think we're even close to thinking about that sort of thing with this single event".

How common are adverse events in drug trials?

Moll added that the European Union pharma industry wants to ensure that a rapid vaccine will in no way be at the expense of people's safety. If AstraZenecas review finds the adverse event is related to the vaccine, all the doses already manufactured will be thrown away, Collins said.

But Health Minister Gan Kim Yong, who was also at the press conference, cautioned: "It's important for us to bear in mind that while we remain hopeful that a vaccine will come one day, in the meantime, we have to continue to be vigilant and ensure that our safe distancing measures are in place". He also tweeted later that almost a third of Americans say they would decline a free, government-approved COVID-19 vaccine.