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(Adds AstraZeneca comment)
By Michael Erman
Feb 22 (Reuters) - Drugmakers should test any COVID-19
vaccines that have been retooled to combat new variants of the
coronavirus in clinical trials designed to track the immune
response of hundreds of subjects, which could take months, U.S.
regulators said on Monday.
Vaccine developers may need to modify their shots to provide
protection against new variants of the coronavirus that turn up
in the United States should they fail to elicit an immune
response in their current form, the U.S. Food and Drug
Administration said in a statement.
The FDA said it believes currently authorized vaccines from
Pfizer Inc with partner BioNTech SE and Moderna
Inc are effective against variants currently
circulating in the United States.
Acting FDA Commissioner Janet Woodcock said drugmakers
should not wait until a mutated virus is demonstrated to be able
to escape the vaccines to begin developing new versions.
"We need to anticipate this and work on it, so that we have
something in our back pocket before the threshold is upon us,"
she said at a news conference.
The emergence of new, more contagious variants has prompted
the U.S. government to step up efforts to track coronavirus
mutations and try to keep vaccines and treatments effective
against any new variants.
Pfizer and Moderna have both said they plan to run clinical
trials of versions of their vaccines that have been redesigned
to combat the highly contagious COVID-19 variant that has become
prevalent South Africa and has turned up in several U.S. States.
AstraZeneca Plc, which is running a U.S. trial for
its coronavirus vaccine, would be able to quickly adapt to new
variants in the laboratory, said Ruud Dobber, company president,
North America, in prepared remarks ahead of a U.S. Congressional
hearing on Tuesday.
"It is likely the process from start to finished product
would take 8 to 9 months to complete. In addition, it will be
important to test the effectiveness of the new vaccine against
the new variants in a clinical trial," Dobber said.
The FDA made its comments as part of a newly updated
guidance http://bit.ly/3pEGUPH for companies making vaccines,
tests and therapeutics for COVID-19. (http://bit.ly/3pEGUPH)
As part of the updated guidance, the FDA recommended that
vaccine makers test any modified vaccines in both unvaccinated
and vaccinated people. The manufacturers should compare the
immune response of a modified vaccine against both the new
variant as well as the original virus.
The FDA also recommended monitoring test subjects' safety
for at least seven days, to support emergency use authorization
for modified vaccines.
The agency is trying to allow drugmakers to make the change
with a minimal amount of extra data needed, said Dr. Peter
Marks, director of the FDA’s Center for Biologics Evaluation and
Research.
Still, the type of trial the agency wants, "might take a few
months, whether it be two or three," Marks said. "I can't say
exactly how long but again, that type of the scale of the amount
of time."
"We want to be ready so that we can move it into production,
when it's ready and when it's needed," he said.
(Additional reporting by Manojna Maddipatla and Mrinalika Roy
in Bengaluru; Editing by Jonathan Oatis and Bill Berkrot)
