AstraZeneca shares tumble after suspending coronavirus vaccine trials

AstraZeneca's suspension of global trials of its coronavirus vaccine dubbed AZD1222 triggered a 2 percent drop in its shares in London and a 12 plunge in the stock price of its Indian unit, AstraZeneca Pharma India Ltd.

The company is developing the AZD1222 vaccine with the University of Oxford.

The suspension, which dimmed the company's prospect of an early rollout, was necessary to review safety data after an unexplained illness in a participant.

AstraZeneca said that the suspension was routine every time there is a potentially unexplained illness in the trials.

The company is working to expedite the review to minimize any potential impact on the trial timeline.

The decision on restarting the trial will be taken by the medical regulator, the MHRA, that would take only days.

According to a New York Times report, citing a person familiar with the situation, the UK-based participant was found to have transverse myelitis, an inflammation that affects the spinal cord and is often sparked by viral infections.

Whether the condition was directly linked to AZD1222 remains unclear.
The AZD1222 has been described by the World Health Organization (WHO) as probably the world’s leading and the most advanced vaccine.

The vaccine is in late-stage clinical trials in the US, the UK, Brazil, and South Africa.

Additional trials are planned in Russia and Japan, targetting up to 50,000 participants globally.

The participant's reaction to AZD1222 has impacted clinical trials by other vaccine makers, which are on the lookout for similar reactions.