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(Adds details from EMA statement, background)
Feb 25 (Reuters) - Europe's medicines regulator said on
Thursday it has issued new guidance for drug makers that modify
their COVID-19 vaccines to protect against variants of the virus
to speed up the approval process.
The move comes after variants first identified in Brazil,
Britain and South Africa spread around the world, piling
pressure on governments struggling to tame the pandemic which
has killed more than 2.5 million people.
Drugmakers including Pfizer, Moderna and
AstraZeneca have been testing their vaccines against
several fast-spreading, more infectious variants of the
coronavirus.
The European Medicines Agency (EMA) said it assumes any new
variant vaccine would largely rely on the same technology as the
parent vaccine, so regulatory focus would be on the immune
response.
"Large-scale safety and efficacy studies are not needed,"
the EU regulator said, adding it recommends that at least one
clinical trial would be conducted in subjects not vaccinated and
never infected with SARS-Cov-2.
A small group of subjects should be randomly selected to
receive either the parent or the variant vaccine as part of a
bridging study to test the immune response, it said.
The EU agency said manufacturers should also study the
efficacy of the variant vaccine when given as a single dose - as
a booster - to people previously vaccinated with the parent
vaccine.
The immune response induced by one dose of the variant
vaccine against the variant strain should be compared with that
recorded during clinical trials with the parent vaccine against
the parent strain of the virus, it said.
No further laboratory studies are required to support the
development of variant vaccines. It also expects the variant
vaccines to be produced by the same manufacturer, and in line
with processes and controls used for the parent vaccine, it
said.
(Reporting by Yadarisa Shabong in Bengaluru and Emilio Parodi
in Milan; Editing by Arun Koyyur and Josephine Mason)
