London - An experimental coronavirus
vaccine being developed by AstraZeneca and Oxford university was
safe and produced an immune response in early-stage clinical
trials, data showed on Monday, keeping alive the hope it could
be in use by the end of the year.
The vaccine, called AZD1222, has been described by the World
Health Organization's chief scientist as the leading candidate
in a global race to halt a pandemic that has claimed more than
600,000 lives.
More than 150 possible vaccines are in various stages of
development with U.S. drugmaker Pfizer and China's CanSino
Biologics also reporting positive responses for their candidates
on Monday.
The vaccine from AstraZeneca and Britain's
University of Oxford did not prompt any serious side effects and
elicited antibody and T-cell immune responses, according to
trial results published in The Lancet medical journal, with the
strongest response seen in people who received two doses.
UK Prime Minister Boris Johnson, whose government has helped
to fund the project, hailed the results as "very positive news."
However, the researchers cautioned the project was still at
an early stage.
"There is still much work to be done before we can confirm
if our vaccine will help manage the Covid-19 pandemic," vaccine
developer Sarah Gilbert said.
"We still do not know how strong an immune response we need
to provoke to effectively protect against SARS-CoV-2 infection,"
she said, adding researchers needed to learn more about Covid-19
and continue late stage trials which have already commenced.
AstraZeneca shares surged 10%, but then gave up most of
those gains, to trade 1.2% stronger on the day.
AstraZeneca has signed agreements with governments around
the world to supply the vaccine should it prove effective and
gain regulatory approval. The company has said it will not seek
to profit from the vaccine during the pandemic.
Adrian Hill, the director of Oxford university's Jenner
Institute, said early projections that a million doses of the
vaccine could be made by September could be an under-estimate,
depending on how quickly late-stage trials can be completed.
He added it remained possible that the vaccine could be in
use by the end of the year.
Researchers said the vaccine caused minor side effects more
frequently than a control group, but some of these could be
reduced by taking paracetamol.
AZD1222 was developed by Oxford university and licensed to
AstraZeneca, which has put it into large-scale, late-stage
trials to test its efficacy. It has also already signed deals to
produce and supply over 2 billion doses of the shot.
The new trial included 1,077 healthy adults aged 18-55 years
with no history of Covid-19.