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By Kate Holton and Josephine Mason
LONDON, Nov 23 (Reuters) - AstraZeneca said on
Monday its vaccine for the novel coronavirus could be around 90%
effective without any serious side effects, the latest drugmaker
to unveil positive interim data in a scientific race to curb a
global pandemic.
The vaccine developed by Oxford University was 90% effective
in preventing COVID-19 when it was administered as a half dose
followed by a full dose at least one month apart, according to
data from the late-stage trials in Britain and Brazil.
No serious safety events related to the vaccine have been
confirmed and it was well tolerated across both dosing regimens,
it said.
"This vaccine's efficacy and safety confirm that it will be
highly effective against COVID-19 and will have an immediate
impact on this public health emergency," Pascal Soriot, Astra's
chief executive, said in a statement.
The British drugmaker's preliminary trial results mark a
fresh breakthrough in the fight against a pandemic that has
killed nearly 1.4 million people and roiled the global economy.
British Prime minister Boris Johnson said it was "incredibly
exciting news the Oxford vaccine has proved so effective in
trials."
AstraZeneca shares fell 1.1% in early morning trade, defying
expectations for a bounce and underperforming the wider market
with the FTSE 100 index rising 0.5% at the open.
Another dosing regimen showed 62% efficacy when given as two
full doses at least one month apart, and the combined analysis
from both dosing regimens resulted in an average efficacy of
70%. All results were statistically significant.
The interim analysis was based on 131 infections among
participants who received the vaccine and those in a control
group who were given an established meningitis shot.
The data showing a range of efficacy between 60% and 90%
comes after U.S. rivals published interim data in recent weeks
showing efficacy of more than 90%.
While the efficacy reading from Astra's viral vector vaccine
is lower than its U.S. rivals, the data will boost confidence
about the chances of successfully developing a variety of
vaccines using different approaches. Public health experts say
the world will need many vaccines to meet global demand.
On Nov. 16, U.S.-based Moderna Inc said its
experimental vaccine proved to be 94.5% effective based on an
early data analysis.
A week earlier, Pfizer Inc and Germany's BioNTech SE
said their vaccine candidate had demonstrated
greater than 90% efficacy that rose to 95% with analysis of full
trial data.
Russia's Sputnik-V vaccine on Nov. 11 was also shown to be
more than 90% effective, though only based on 20
infections.
The AstraZeneca vaccine uses a modified version of a
chimpanzee common cold virus to deliver instructions to cells to
fight the target virus, which is different than the new
technology known as messenger RNA (mRNA) deployed by
Pfizer/BioNTech and Moderna.
The company - one of the UK's most valuable listed companies
- will now immediately prepare regulatory submission of the data
to authorities around the world that have a framework in place
for conditional or early approval.
It will also seek an emergency use listing from the World
Health Organization to speed up availability in low-income
countries. In parallel, the full analysis of the interim results
is being submitted for publication in a peer-reviewed journal.
(Reporting by Kate Holton in London and Josephine Mason; Aakash
Jagadeesh Babu in Bengaluru; Editing by Guy Faulconbridge and
Christopher Cushing)
