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Nov 26 (Reuters) - AstraZeneca is likely to run an
additional global trial to assess the efficacy of its COVID-19
vaccine, its chief executive Pascal Soriot was quoted as saying
on Thursday after questions over the results from its late-stage
study.
Instead of adding the trial arm to an ongoing U.S. process,
a new study would be run to evaluate a lower dosage that
performed better than a full amount in AstraZeneca's studies,
Soriot was quoted as saying in a Bloomberg News report.
"Now that we've found what looks like a better efficacy we
have to validate this, so we need to do an additional study,"
Soriot was quoted as saying in the report.
Soriot said it would probably be another "international
study, but this one could be faster because we know the efficacy
is high so we need a smaller number of patients".
The news comes as AstraZeneca faces questions about its
success rate that some experts say could hinder its chances of
getting speedy U.S. and EU regulatory approval.
Several scientists have raised doubts about the robustness
of results showing the experimental vaccine was 90% effective in
a sub-group of trial participants who, by error initially,
received a half dose followed by a full dose.
(Writing by Josephine Mason;
Editing by Jan Harvey and Alexander Smith)
