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By Polina Nikolskaya
MOSCOW, Feb 4 (Reuters) - Human trials of a COVID-19 vaccine
combining a British shot from AstraZeneca and Oxford
University with Russia's Sputnik V vaccine will begin next week
in Azerbaijan and some Middle Eastern nations, a Russian
official said on Thursday.
AstraZeneca said in December it would start clinical trials
to test combining the two vaccines to see if this could boost
the efficacy of the British shot.
Both vaccines involve two doses, an initial shot and a
booster, and use harmless adenoviruses as vehicles, or vectors,
to carry genetic instructions into the body to prompt cells to
produce antibodies. Sputnik, however, uses different viral
vectors for its two shots.
A two-dose regimen of Sputnik V was 91.6% effective against
symptomatic COVID-19, according to peer-reviewed late-stage
trial results published in The Lancet international medical
journal.
Russia is ready to offer a collaboration with Sputnik V to
any producer that has a vaccine with efficacy less than 90%,
Kirill Dmitriev, the head of Russia's RDIF sovereign wealth
fund, told Reuters on Thursday. Pooled late-stage trial data
showed AstraZeneca's shot was about 70% effective.
Britain also launched a trial on Thursday to assess immune
responses if a dose of AstraZeneca's vaccine is combined with
one from Pfizer and BioNTech in a two-shot
schedule.
"Sputnik was the first in the world to suggest that the two
shots should be different to give a stronger and longer immune
response, more mutation-proof," Dmitriev said.
"So what others are starting to do with this kind of trial
is to follow our steps," he said, adding RDIF would also
announce a joint trial with a large Chinese company soon.
He said hundreds of people in different countries would
participate in the trial with AstraZeneca. It has already been
approved by several regulators and patient recruitment started
last week, Sputnik V's official Twitter account said.
Trials will also be held in Argentina, Saudi Arabia, the
UAE, Belarus, Russia, Ukraine and elsewhere, Reuters has
reported. Participants will first receive the AstraZeneca
vaccine and then the Sputnik V shot 29 days later.
The first results are expected in March, Dmitriev said.
(Reporting by Polina Nikolskaya; Editing by Jon Boyle and Mark
Potter)
