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By Kate Holton and Josephine Mason
LONDON, Nov 23 (Reuters) - Britain’s AstraZeneca
said on Monday its vaccine for the novel coronavirus could be
around 90% effective without any serious side effects, giving
the world another important tool to halt the COVID-19 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.
AstraZeneca will have 200 million doses by the end of 2020,
with 700 million doses ready globally by the end of the first
quarter of 2021, operations executive Pam Cheng said on Monday.
The vaccine's effectiveness depended on the dosing, and fell
to just 62% when given as two full doses rather than a half-dose
first. But scientists cautioned against seeing this as evidence
that it would be less useful than rival vaccines from Pfizer
and Moderna, which each prevented about 95% of
cases according to interim data from their late-stage trials.
"I think it is a real fool's errand to start trying to pick
these three (Pfizer/Moderna/Astra) apart on the basis of
snippets of phase 3 data from press releases," said Danny
Altmann, professor of immunology at Imperial College London.
"For the bigger picture, my suspicion is that by the time we
are a year down the line, we'll be using all three vaccines with
about 90% protection - and we'll be a lot happier."
Scientists also noted there may be advantages to
AstraZeneca's vaccine.
"Importantly, from what we have heard the vaccine seems to
prevent infection not just disease. This is important as the
vaccine could reduce the spread of the virus as well as protect
the vulnerable from severe disease," said Peter Horby, a
professor of emerging infectious diseases and global health at
the University of Oxford,
AstraZeneca's vaccine can also be distributed more easily
because it can be kept at refrigerator temperature, unlike the
drugs from Pfizer and Moderna which have to be stored frozen.
That would make the AstraZeneca shot easier to transport and
store globally, particularly in lower and middle-income
countries.
'INCREDIBLY EXCITING'
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.
Britain is among countries that pre-bought large quantities
of the new vaccine. Officials said its success means normal life
can return sooner. It was "incredibly exciting news the Oxford
vaccine has proved so effective in trials," said Prime Minister
Boris Johnson.
There would be 20 million doses in Britain by the end of the
year, with 70 million doses for the UK by the end of Q1 2021.
Shares and oil prices rose as investors bet the rollout of
another vaccine would revive the global economy next year even
as virus case numbers surge.
The STOXX index of Europe's 600 largest shares rose
0.5% to its highest since February but AstraZeneca shares fell
more than 2% as traders perceived the efficacy data as
disappointing compared with rivals.
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.
Public health experts say the world will need many vaccines
to meet global demand.
The AstraZeneca vaccine uses a modified version of a
chimpanzee common cold virus to deliver instructions to cells to
fight the target virus, a different approach from the new
technology known as messenger RNA (mRNA) deployed by
Pfizer/BioNTech and Moderna.
AstraZeneca, one of Britain'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, Josephine Mason and Aakash Jagadeesh
Babu
Writing by Josephine Mason and Peter Graff
Editing by Guy Faulconbridge, Christopher Cushing and Carmel
Crimmins)
