Oxford-AstraZeneca COVID-19 vaccine trial put on hold after participant suffers adverse reaction

Key highlights

•Final clinical trials of the Oxford-AstraZeneca’s coronavirus vaccine have been temporarily halted after a participant falls ill

•However, details of the study participant’s adverse reaction were not immediately known

•Worldwide, COVID-19 has so far claimed at least 893,524 lives and infected as many as 27,387,170 people

A large, phase 3 clinical study testing a potential coronavirus vaccine developed by the University of Oxford has been temporarily put on hold after a volunteered had an adverse reaction in the UK. British pharmaceutical company AstraZeneca, which is developing the vaccine alongside Oxford University, called it as a ‘routine pause’ in the case of ‘an unexplained illness’.

“As part of the ongoing randomized, controlled global trials of the Oxford coronavirus vaccine, our standard review process was triggered and we voluntarily paused vaccination to allow review of safety data by an independent committee,” a spokesperson said in a statement.

“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,” reported AFP.

The Oxford-AstraZeneca’s COVID-19 vaccine is seen as a strong contender among dozens of candidates that are being developed globally. The vaccine moved into phase 3 testing involving some 30,000 participants in the US as well as in the UK, Brazil and South Africa. However, all international trials have now been halted while an independent investigation reviews the safety data before regulators decide whether the trial can restart, reported the BBC’s Medical Editor Fergus Walsh.

AstraZeneca said illnesses will sometimes happen by chance in large trials but must be reviewed independently. Perhaps, holds during clinical trials are not uncommon.

“We are working to expedite the review of the single event to minimise any potential impact on the trial timeline,” the spokesperson added.

According to reports, it was not immediately clear where the patient was, or the nature and severity of their illness. However, Stat News, citing a source familiar with the matter, reported that the participant is expected to recover.

The vaccine, called AZD1222, uses a weakened version of a common cold-causing adenovirus that has been engineered to code for the spike protein that the novel coronavirus uses to invade cells.

This is the second time the Oxford’s Covid-19 vaccine trial has been put on hold, according to the BBC News. It is believed that the trials could resume in a matter of days, although AstraZeneca did not provide any details on when the trial is expected to resume.

As per the World Health Organization (WHO), close to 180 vaccines are being tested against COVID-19 all over the world but none has completed clinical trials yet.