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* UK PM Johnson says supply is limiting rollout
* AstraZeneca says on track to deliver 2 million weekly
shots
* Industry bodies cautious about changing dose regimes
By Alistair Smout and William James
LONDON, Jan 13 (Reuters) - Britain is targeting a 24-hour,
7-day a week vaccination programme as soon as possible, Prime
Minister Boris Johnson said on Wednesday, as he bids to step up
the pace of the rollout and give shots to at-risk groups by
mid-February.
AstraZeneca executives said the company was on track to
deliver 2 million doses a week before mid-February, and Johnson
said the availability of more shots would be crucial to scaling
up to a round-the-clock service.
"We'll be going to 24/7 as soon as we can," Johnson told
parliament. "At the moment the limit is on supply."
Johnson hopes that giving protection to the elderly, the
vulnerable and frontline workers by mid-February will provide a
route out of a new national lockdown which began in England last
week.
Scotland, which locked down at the same time, said on
Wednesday it would tighten its measures further.
Across the United Kingdom, there are 15 million people in
the highest priority groups. Only 2.4 million have been
vaccinated so far, so the government needs more than 2 million
vaccinations a week to hit its target.
Britain is rolling out two vaccines, one made by AstraZeneca
and one by Pfizer.
Earlier, health minister Matt Hancock said Britain was on
track to meet the target, and manufacturers were delivering
vaccine on schedule, but the process would become smoother as it
moves along.
AstraZeneca UK President Tom Keith-Roach said he hoped to be
able to expand supply beyond 2 million doses a week as processes
were optimised, but couldn't promise it would be possible.
"We can't commit to a number above 2 million, but obviously
it may be possible," he told lawmakers.
Britain is prioritising giving as many people as possible
first doses of the vaccine, allowing up to 12 weeks before a
second dose.
AstraZeneca research chief Mene Pangalos supported the move,
saying data showed an 8-12 week gap was a "sweet spot" for
efficacy.
Pfizer has been more cautious, warning that there is no data
to support delaying the second dose of its shot beyond 21 days,
and other industry voices echoed that wariness.
"The biopharmaceutical industry supports adhering to the
dosing that has been assessed in clinical trials," a group of
industry bodies including Vaccines Europe and the International
Federation of Pharmaceutical Manufacturers and Associations said
in a statement.
It said any changes "should follow the science and be based
on a transparent deliberation of the available data".
(Reporting by Alistair Smout, William James, Elizabeth Piper
and Estelle Shirbon; Editing by Giles Elgood)
