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LONDON, Sept 9 (Reuters) - AstraZeneca has paused
global trials of its experimental coronavirus vaccine after an
unexplained illness in a participant, denting the British
drugmaker's shares on Wednesday as the move was seen as dimming
prospects for an early rollout.
On Tuesday, AstraZeneca said it voluntarily paused trials,
including late-stage ones, to allow an independent committee to
review safety data, and it was working to expedite the review to
minimise any potential impact on the trial timeline.
The vaccine, which AstraZeneca is developing with the
University of Oxford, has been described by the World Health
Organization (WHO) as probably the world's leading candidate and
the most advanced in terms of development.
"It is obviously a challenge to this particular vaccine
trial," Britain's Health Secretary Matt Hancock told Sky News,
adding: "It's not actually the first time this has happened to
the Oxford vaccine".
The trial's suspension triggered a 2% fall in AstraZeneca's
shares in London and a 12% drop in the stock price of its Indian
unit, AstraZeneca Pharma India Ltd. AstraZeneca
shares, which have the second biggest weighting in the FTSE 100
index, were down 0.3% at 0820 GMT.
It follows reports that the United States was aiming for a
fast-track approval before the November presidential election.
Asked whether the pause would set back the vaccine
development process, Britain's Hancock said: "Not necessarily,
it depends on what they find when they do the investigation."
The BBC reported that a final decision on restarting the
trial will be taken by the medical regulator the MHRA, which
could take only days.
"This is a routine action which has to happen whenever there
is a potentially unexplained illness in one of the trials," the
AstraZeneca said in an emailed statement.
The nature of the illness was not disclosed, although the
participant is expected to recover, according to Stat News,
which first reported the suspension due to a "suspected serious
adverse reaction".
The U.S. Food and Drug Administration defines an adverse
event as one in which evidence suggests a possible relationship
to the drug being tested.
A New York Times report citing a person familiar with the
situation said a participant based in Britain was found to have
transverse myelitis, an inflammatory syndrome that affects the
spinal cord and is often sparked by viral infections.
Whether this was directly linked to AstraZeneca's vaccine
remains unclear, the report said. AstraZeneca declined to
comment.
'HISTORIC PLEDGE'
Called AZD1222, the vaccine is in late-stage clinical trials
in the United States, Britain, Brazil and South Africa and
additional trials are planned in Japan and Russia. The trials
aim to enrol up to 50,000 participants globally.
South Korea said on Wednesday it would look into the
suspension and review its plan to participate in the
manufacturing of the vaccine.
"It's not rare that clinical trials get suspended as various
factors interact," health ministry official Yoon Tae-ho told a
briefing.
The decision to put the trial on hold has impacted clinical
trials being conducted by other vaccine makers, which are
looking for signs of similar reactions, Stat said.
The U.S. National Institutes of Health, which is providing
funding for AstraZeneca's trial, declined to comment.
Moderna said in an emailed statement it was "not aware of
any impact" to its ongoing COVID-19 vaccine study at this time.
Nine leading U.S. and European vaccine developers pledged on
Tuesday to uphold scientific safety and efficacy standards for
their experimental vaccines despite the urgency to contain the
coronavirus pandemic.
The companies, including AstraZeneca, Moderna and Pfizer,
issued what they called a "historic pledge" after a rise in
concern that safety standards might slip in the face of
political pressure to rush out a vaccine.
The companies said they would "uphold the integrity of the
scientific process as they work towards potential global
regulatory filings and approvals of the first COVID-19
vaccines."
The other signatories were Johnson & Johnson, Merck
& Co, GlaxoSmithKline, Novavax Inc,
Sanofi and BioNTech.
(Reporting by Guy Fauconbridge, Estelle Shirbon, Kate Kelland
in London, Deena Beasley; Additional reporting by Peter
Henderson in San Francisco, Rocky Swift in Tokyo, Sangmi Cha in
Seoul and Miyoung Kim in Singapore; Editing by Alexander Smith)
