Last checked at 
* First results of tests on new variants encouraging
* More studies needed
* Variants found in South Africa, Britain more infectious
(Adding detail throughout)
By Michael Erman
NEW YORK, Jan 7 (Reuters) - Pfizer Inc and
BioNTech's COVID-19 vaccine appeared to work against a
key mutation in the highly transmissible new variants of the
coronavirus discovered in Britain and South Africa, according to
a laboratory study conducted by the U.S. drugmaker.
The study by Pfizer and scientists from the University of
Texas Medical Branch, which has not yet been peer-reviewed,
indicated the vaccine was effective in neutralizing virus with
the so-called N501Y mutation of the spike protein.
The mutation could be responsible for greater
transmissibility and there had been concern it could also make
the virus escape antibody neutralization elicited by the
vaccine, said Phil Dormitzer, one of Pfizer's top viral vaccine
scientists.
The first results of tests on the variants offer a glimmer
of hope while more studies are carried out as Britain and other
countries try to tame the more infectious variants which
authorities believe are driving a surge in infections that could
overwhelm healthcare systems.
The Pfizer-BioNTech study was conducted on blood taken from
people who had been given the vaccine. Its findings are limited
because it does not look at the full set of mutations found in
either of the new variants of the rapidly spreading virus.
Dormitzer said it was encouraging that the vaccine appears
effective against the mutation, as well as 15 other mutations
the company has previously tested against.
"So we've now tested 16 different mutations, and none of
them have really had any significant impact. That's the good
news," he said. "That doesn't mean that the 17th won't."
Dormitzer said another mutation found in the South African
variant, called the E484K mutation, was also concerning.
The researchers plan to run similar tests to establish
whether the vaccine is effective against other mutations found
in the British and South African variants and hope to have more
data within weeks.
The variants are said by scientists to be more transmissible
than previously dominant ones, but they are not thought to cause
more serious illness.
Scientists said the results of the study would help calm
concerns that people will not be protected by vaccines being
given to millions of people around the world in the fight
against the pandemic, which has killed more than 1.8 million
people and roiled economies.
But they cautioned that more clinical tests and data are
still needed to come to a definitive conclusion.
"This is good news, mainly because it is not bad news," said
Stephen Evans, professor of pharmacoepidemiology, London School
of Hygiene & Tropical Medicine.
"So, yes this is good news, but it does not yet give us
total confidence that the Pfizer (or other) vaccines will
definitely give protection."
TESTS AND TWEAKS
AstraZeneca, Moderna and CureVac
are also testing whether their shots work against the
fast-spreading variants. They have said they expect them to be
effective, but the timing of those studies are not known.
A senior British lawmaker expressed concerns in an interview
on Friday that COVID-19 vaccines might not work properly against
the South African variant. He was not responding to questions
about Friday's data.
The Pfizer/BioNTech vaccine and the one from Moderna Inc
, which use synthetic messenger RNA technology, can be
quickly tweaked to address new mutations of a virus if
necessary. Scientists have suggested the changes could be made
in as little as six weeks.
The variant is not the first of the pandemic to emerge and
Eleanor Riley, professor of immunology and infectious disease at
the University of Edinburgh, said these types of study will be
needed as they appear.
"It may be necessary to tweak the vaccine over time," she
said.
(Reporting by Michael Erman; Writing by Josephine Mason;
Editing by Bill Berkrot, Edwina Gibbs and Timothy Heritage)
