Covid-19 vaccine trial

untarily paused vaccination to allow a review of safety data by an independent committee,” said AstraZeneca.

“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,” the pharmaceutical added.

According to a BBC report, this is the second time such a pause has happened with the Oxford University-AstraZeneca coronavirus vaccine trial since the first volunteers were immunised in April.

For now, all international vaccination sites, in the UK, Brazil, South Africa, and the US are on hold until a final decision on restarting the trial is taken by the UK’s medical regulator the Medicines and Healthcare products Regulatory Agency (MHRA).

Two other vaccines which are currently undergoing large testings in the US include one by Moderna Inc, and the other by Pfizer and Germany’s BioNTech. About two-thirds of the needed participants have already been recruited for the studies.

Temporary holds of large medical studies are not unusual as investigations of unexpected reactions among participants are a mandatory safety step. In a follow-up statement, first reported by Stat News, AstraZeneca said it initiated the study hold.

Details of the unexplained illness have not been released, and the nature of the adverse reaction and when it happened was not immediately known.

The World Health Organisation (WHO) has reiterated that the safety of a prospective vaccine for Covid-19 comes “first and foremost”.

“Just because we talk about speed ... it doesn’t mean we start compromising or cutting corners on what would normally be assessed,” Soumya Swaminathan, the WHO’s chief scientist said during a WHO COVID-19 update.