NEW YORK, June 30 (Reuters) - U.S. health regulators will
not require companies to submit new clinical trial data on
COVID-19 vaccines that target the now dominant BA.4 and BA.5
Omicron subvariants to authorize those shots, but will instead
rely on studies showing the efficacy of targeting the earlier
BA.1 subvariant, a top official said on Thursday.
Dr. Peter Marks, a senior official overseeing vaccines at
the U.S. Food and Drug Administration, told Reuters the agency
would also consider manufacturing data specific to a BA.4 and
BA.5 vaccine, and that preclinical data from animal studies and
safety data for those shots could also be available.
The FDA on Thursday recommended COVID-19 vaccine
manufacturers Pfizer Inc/BioNTech SE and
Moderna Inc change the design of their booster shots
beginning this fall to include components tailored to combat
BA.4 and BA.5. It plans to review them for emergency use
"It's very similar to what we do with influenza strain
changes where there will be a couple of amino acids difference,
but we don't expect any difference in the safety that we're
going to see," Marks said.
He said he expects the immune response to the BA.4/5 booster
shot to be similar to that seen with BA.1.
"We're very comfortable doing this, because it will help us
get ahead of things," Marks said.
The FDA has directed manufacturers to launch human clinical
trials to study the BA.4/5 vaccines, but said that data will be
used to gauge the continued effectiveness of the boosters
against new variants that may arise.
Marks said he believes regulators from other countries are
seriously considering using BA.1-based vaccines, which some
drugmakers have already been producing and may be available
"I will tell you that globally - just so you understand -
different regulators feel different levels of comfort with
this," Marks said.
He said the United States should run a wider vaccination
campaign this fall than the one in the spring, when the focus
was on older and other high-risk people.
"I actually think that this fall we have to go all out on
our booster campaign," Marks said.
"It's going to be really critical as we move into this fall
where we've seen this evolution into BA4/5, where we could see
further evolution, to try to get as many people boosted as we
(Reporting by Michael Erman
Editing by Bill Berkrot and Rosalba O'Brien)