Oct 13 (Reuters) - People who got Johnson & Johnson Incs
COVID-19 vaccine as a first shot had a stronger immune
response when boosted with vaccines from Pfizer Inc
/BioNTech SE or Moderna Inc, a study
run by the National Institutes of Health showed on Wednesday.
The study, which is preliminary and hasn't been peer
reviewed, is the latest challenge to J&J's efforts to use its
COVID-19 vaccine as a booster in the United States.
The study, which included more than 450 adults who received
initial shots from Pfizer, Moderna, or Johnson & Johnson, showed
that "mixing and matching" booster shots of different types is
safe in adults. Moderna's and Pfizer's vaccines are based on
messenger RNA while J&J's uses viral vector technology.
It comes as an advisory group to the U.S. Food and Drug
Administration is preparing to meet later this week to discuss
the merits of a booster shot for Moderna and J&J vaccines.
FDA officials on Wednesday said J&J's regulatory submission
for its planned booster raised red flags including small sample
sizes and data based on tests that had not been validated.
U.S. health officials have been under pressure to offer
advice on booster doses of the J&J and Moderna COVID-19 vaccines
after the White House announced in August it planned to roll out
boosters beginning last month for most adults.
The NIH study contrasted the safety and immune response of
volunteers who were boosted with the same type of shot they had
been given for their initial vaccination with those who received
a different type of shot as a booster.
Mixing and matching doses for a booster produced similar
side effects to those seen in primary inoculations and raised no
significant safety concerns, the study said.
The study of the three COVID-19 vaccines currently
authorized in the United States showed that using different
types of shots as boosters generally appeared to produce a
comparable or higher antibody response than using the same type.
The trial took place in 10 U.S. cities and used a total of
nine combinations of initial shots and boosters.
Mixing booster doses "may offer immunological advantages to
optimize the breadth and longevity of protection achieved with
currently available vaccines," researchers wrote in the study.
(Reporting by Amruta Khandekar and Carl O'DOnnell; Additional
reporting by Julie Steenhuysen; Editing by Maju Samuel, Jonathan
Oatis and Diane Craft)