PARIS, Jan 28, 2021 (BSS/AFP) – The vaccine made by Pfizer and BioNTech
appears to retain its effectiveness against coronavirus mutations in worrying
new variants that have emerged recently in Britain and South Africa, the
firms said Thursday.
Several new variants — each with a cluster of genetic mutations — have
sparked fears over an increase in infectiousness as well as suggestions that
the virus could begin to elude immune response, whether from prior infection
or a vaccine.
Pfizer/BioNTech, which had previously said it was unlikely that the strain
originally found in Britain could escape vaccine protection, said Thursday
that early tests suggest their immunisation would be similarly protective
against the variant in South Africa.
In a statement, the two companies said these preliminary findings “do not
indicate the need for a new vaccine to address the emerging variants”.
They said they are “prepared to respond” if a new strain is shown to be
able to evade the immunity of the vaccine, adding that they can produce
updates to their jab if needed.
The statement comes after US biotech firm Moderna this week announced that
lab studies suggest its vaccine should protect against the variants first
found in the United Kingdom and South Africa.
The latest Pfizer/BioNTech research, which has not yet been peer reviewed,
was carried out by researchers from Pfizer and the University of Texas.
The authors compared the antibodies of 20 people who had received two doses
of the Pfizer/BioNTech vaccine during clinical trials with lab-engineered
sets of mutations present in the variants that emerged in Britain and South
Africa.
– ‘Escape’ fears –
The new variants — along with another linked to Brazil — have mutations
to the virus’ spike protein, which enables the virus to latch onto human
cells and therefore plays a key role in driving infections.
One mutation in particular — known as E484K and found in the South Africa
and Brazil strains but not the one in Britain — has experts particularly
worried about immunity “escape”.
The study found that the antibodies were able to neutralise all the sets of
mutations tested.
It noted that the effect was “slightly lower” against three mutations in
the variant found in South Africa, including E484K.
But the firms said that it was “unlikely to lead to a significant reduction
in the effectiveness of the vaccine”.
They said they were looking to test against the full set of mutations in
the spike protein of the variant that emerged in South Africa.
A study released last week by researchers in South Africa, which has also
not yet been peer reviewed, tested the variant found there against blood
plasma from recovered Covid-19 patients.
They found that it was resistant to neutralising antibodies built up from
prior infection, but said more research was needed into the effectiveness of
other parts of the immune response.
Daily global deaths from Covid-19 topped 18,000 for the first time
Wednesday, with vaccines seen as the only real chance of returning to some
form of normality.
The German firm BioNTech had already said the messenger RNA technology
means it could update the vaccine against new variants within weeks.