It was a very  disappointing piece of news – Astrazeneca said that it had paused global trials of its coronavirus vaccine because of an unexplained illness in one of the volunteers. It's a standard precaution in vaccine trials that is meant to ensure experimental vaccines do not cause serious reactions among participants.

This is the same ‘Oxford’ vaccine on which the entire world has pinned its hopes. This is being developed with Britain's University of Oxford.

The company said, “In large trials, illnesses will happen by chance but must be independently reviewed to check this carefully. We are working to expedite the review of the single event to minimize any potential impact on the trial timeline. We are committed to the safety of our participants and the highest standards of conduct in our trials.”

The stock is the top loser on the BSE since the opening bell, going down 13.5% to Rs.3650 levels. It has recouped and is now at Rs.3834 levels. Its 20% LC for the day is at Rs.3371.85.