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By Kate Holton, Josephine Mason and Kate Kelland
LONDON, Nov 23 (Reuters) - AstraZeneca said on
Monday its COVID-19 vaccine could be around 90% effective,
giving the world another weapon to fight the global pandemic and
potentially cheaper to make, easier to distribute and faster to
scale-up than rivals.
The British drugmaker said it will have as many as 200
million doses by the end of 2020 - around four times as many as
U.S. competitor Pfizer. Seven hundred million doses
could be ready globally as soon as the end of the first quarter
of 2021.
The vaccine was 90% effective in preventing COVID-19 when it
was administered as a half dose followed by a full dose at least
a month later, according to data from late-stage trials in
Britain and Brazil. No serious safety events were confirmed, the
company said.
"This means we have a vaccine for the world," said Andrew
Pollard, director of the Oxford University vaccine group that
developed the drug.
The vaccine's cost works out at just a few dollars a shot, a
fraction of the price of drugs from Pfizer and Moderna,
which use a more unconventional technology.
And it can be transported and stored at normal fridge
temperatures, which proponents say would make it easier to
distribute, especially in poor countries, than Pfizer's, which
needs to be shipped and stored at -70C, the sort of temperature
typical of an Antarctic winter.
The effectiveness of AstraZeneca's vaccine 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 rivals.
Vaccines from Pfizer and Moderna 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."
Pascal Soriot, Astra's chief executive, said the data
showing that an initial half dose was more effective than two
full doses was good news, as more people could be vaccinated
faster with a limited supply.
'INCREDIBLY EXCITING'
AstraZeneca's preliminary trial comes as a new wave of
infections has hurt economies, particularly in Europe and the
United States. Nearly 1.4 million people have died in the global
COVID-19 pandemic.
Britain is among countries that pre-bought large quantities
of the AstraZeneca vaccine, and officials there said its success
means normal life can return sooner. Prime Minister Boris
Johnson described the results as "incredibly exciting".
Shares and oil prices rose as investors bet the rollout of
another vaccine would revive the global economy next year.
The STOXX index of Europe's 600 largest shares rose
0.5% to its highest since February. Nevertheless, AstraZeneca's
own shares fell 1.5% as traders perceived the efficacy data as
disappointing compared with rivals.
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 traditional approach to vaccine
development and different from the path taken by Pfizer and
Moderna, which rely on new technology known as messenger RNA
(mRNA).
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.
(Additional reporting by Aakash Jagadeesh Babu and Alistair
Smout; Writing by Peter Graff:
Editing by Guy Faulconbridge, Christopher Cushing and Carmel
Crimmins)
