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* Trial to start by the end of the year - Russia's RDIF
* Boost for Russian vaccine, which has been criticised in
West
* Once COVID-19 vaccine frontrunner, AstraZeneca has slipped
back
By Andrew Osborn and Pushkala Aripaka
Dec 11 (Reuters) - AstraZeneca will start clinical trials to
test a combination of its experimental COVID-19 vaccine with
Russia's Sputnik V shot aimed at boosting the efficacy of the
British drugmaker's vaccine, Russia's sovereign wealth fund said
on Friday.
Trials will start by the end of the year and Russia wants to
jointly produce the new vaccine if it is proven to be effective,
said the RDIF wealth fund, which has funded Sputnik V, named
after the Soviet-era satellite that triggered the space race.
AstraZeneca, in a statement on Friday, said it was
considering how it could assess combinations of different
vaccines, and would soon begin exploring with Russia's Gamaleya
Institute, which developed Sputnik V, whether two common cold
virus-based vaccines could be successfully combined.
It did not give further details. However, its Russian arm
said it would start to enrol adults aged 18 years and older for
the trial.
The co-operation between one of Britain's most valuable
listed companies and the state-backed Russian science research
institute highlights the pressure to develop an effective shot
to fight the pandemic that has killed over 1.5 million people.
The move is likely to be seen in Moscow as a long-awaited
vote of confidence by a Western manufacturer in Sputnik V.
Its Russian developers say clinical trials, still underway,
have shown it has an efficacy rate of over 90%, higher than
AstraZeneca's own vaccine and similar to U.S. rivals Pfizer
and Moderna.
Some Western scientists have raised concerns about the speed
at which Russia has worked, giving the regulatory go-ahead for
its vaccines and launching large-scale vaccinations with Sputnik
V before full trials to test its safety and efficacy have been
completed. Russia has rejected such criticism as unfounded.
The prospective tie-up comes as AstraZeneca, once seen as a
frontrunner in the vaccine race, prepares for further tests to
confirm whether its shot could be 90% effective, potentially
slowing its roll out.
The average efficacy rate was 70.4% in interim late-stage
data.
TWITTER DIPLOMACY
The partnership came about after the developers of Sputnik V
suggested on Twitter last month that AstraZeneca try the
combination after the British drugmaker released interim results
from its late-stage trial.
The British drugmaker accepted the proposal, the RDIF said
on Friday.
"The decision by AstraZeneca to carry out clinical trials
using one of two vectors of Sputnik V in order to increase its
own vaccine’s efficacy is an important step towards uniting
efforts in the fight against the pandemic," said RDIF head
Kirill Dmitriev in a statement.
"We hope that other vaccine producers will follow our
example."
Earlier this week, Kate Bingham, chair of Britain's vaccine
task force, said the country would start trials next year using
combinations of different kinds of vaccine for the initial and
booster vaccinations, in the hope that a "mix-and-match"
approach might maximise the immune response.
Both projects are using harmless adenoviruses as vehicles to
bring genetic instructions into the body to prompt cells to
produce vaccine proteins, an approach that has previously been
used in an Ebola vaccine.
One common challenge of such a method is that the immune
system could attack the adenovirus vehicle, known as the viral
vector, and in particular neutralise the staggered booster shot
that is now an important feature of the leading COVID-19 vaccine
candidates.
Using different viral vectors for the primer and booster
shot is one approach that researchers, including at the Gamaleya
Institute, have pursued. Combining vaccines from different
developers could also be a way around that.
AstraZeneca and partner Oxford University have used a
harmless adenovirus only found in monkeys to rule out that
people receiving the shot had previous exposure and therefore an
immune defence against it.
AstraZeneca did not mention immunity against the viral
vector as an issue in its statement on Friday.
Still, Russian officials have not always been complimentary
about the British vaccine.
When the company paused a clinical trial in September due to
the unexplained illness of a volunteer, Kremlin spokesman Dmitry
Peskov told reporters that Sputnik V was a more reliable vaccine
because it was based on an adenovirus found in humans, whereas
the British candidate was "a monkey vaccine."
The partnership may draw scrutiny after Britain said in July
hackers backed by the Russian state were trying to steal
COVID-19 vaccine and treatment research from academic and
pharmaceutical institutions around the world. The Kremlin
rejected the Western allegations.
The news came as Sanofi and GlaxoSmithKline
said clinical trials of their COVID-19 vaccine showed an
insufficient immune response in older people.
(Reporting by Pushkala Aripaka in Bengaluru and Andrew Osborn
in Moscow; Additional reporting by Ludwig Burger
Writing by Josephine Mason;
editing by Patrick Graham and Mark Potter)
