Covid-19 vaccine trial on hold after “unexplained illness”

Share this information:

It looks like one of the world’s most celebrated and much anticipated Covid-19 vaccine clinical trials have hit a snag.

One of several global companies racing against time to develop a virus against Covid-19, AstraZeneca, announced that it has put on hold its clinical trials worldwide after reporting an adverse reaction in a trial participant in the United Kingdom.

There was no mention of the exact reaction but recovery is expected, according to medical and biotech news site STAT that first broke the news of the halt to the trial.

There was no indication how long the pause of the clinical trial will be. “We are working to expedite the review of the single event to minimize any potential impact on the trial timeline,” AstraZeneca said about the vaccine, which was originally developed at Oxford University.

“This is a routine action which has to happen whenever there is a potentially unexplained illness in one of the trials, while it is investigated, ensuring we maintain the integrity of the trials,” it added.

The interruption represents the first major stumbling block in an otherwise smooth journey in the development of a vaccine against the dreaded Covid-19 virus.

Typically, it is during the conduct of large scale Phase 3 clinical trials, like this one being conducted by AstraZeneca, are where real issues start to surface, which is why they are carried out before a vaccine is approved.

Aside from AstraZeneca’s trial that is now on hold, there are two other large-scale Covid-19 vaccine trials being conducted in the US, one by Pfizer and BioNTech, a German company, and another by Moderna, a biotech firm. 

Photo c/o

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.