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By Benoit Van Overstraeten
PARIS, Dec 15 (Reuters) - Sanofi and
GlaxoSmithKline said on Wednesday a single booster dose
of their COVID-19 vaccine candidate provided strong immune
responses, preliminary data from clinical trials show, a boost
for the drugmakers after lagging the vaccine race.
The French and British partners said they expected more
results of the late-stage Phase III study of their recombinant
adjuvanted COVID-19 vaccine candidate in the first quarter.
They plan to file booster data with regulatory authorities
following the Phase III results.
"The booster was well tolerated, with a safety profile
similar to currently approved COVID-19 vaccines. This is the
most comprehensive booster trial to date to explore boosting
across different vaccine technologies used for primary
vaccination", the companies said in a statement.
"To provide the necessary data to regulatory authorities for
the booster vaccine submission, the trial will continue to
accrue the number of events needed for analysis, with results
expected in Q1, 2022."
No safety concerns were identified.
The vaccine uses the same technology as one of Sanofi's
seasonal influenza vaccines coupled with an adjuvant, a
substance that acts as a booster to the shot, made by GSK.
The news provides some optimism for the companies after
falling behind rivals in the race for COVID-19 shots and big
delays with the development of this shot.
Last year, trials for the shot showed an insufficient immune
response in older people. The companies had said the vaccine
could be approved by the year-end after initially targeting the
first half of the year.
At the end of September, Sanofi dropped its plans for its
own mRNA-based COVID-19 vaccine because of the dominance
achieved by BioNTech-Pfizer and Moderna
in using the technology to fight the pandemic.
BOOSTER SHOT
The booster shot has been tested for all age groups and for
people who have received four of the most widely approved shots
- AstraZeneca, Johnson & Johnson, Moderna and
Pfizer/BioNTech - as part of their primary vaccine.
It was administered between four and ten months after a
complete primary vaccination schedule. The Omicron variant was
not circulating during the trial.
"Preliminary results from the VAT0002 clinical trial
investigating the safety and immunogenicity of the booster
showed neutralizing antibodies increased nine to 43-fold
regardless of the primary vaccine received (AstraZeneca, Johnson
& Johnson, Moderna, Pfizer/BioNTech) and for all age groups
tested", Sanofi said.
The company said this was the most "comprehensive" booster
trial to date as European countries grapple with a new wave of
COVID-19 infections fuelled by the Delta variant of the virus
and are gearing up for the new more contagious Omicron variant.
Sanofi also it was continuing "its contribution to global
public health needs" with the manufacturing of up to half a
billion doses from BioNTech/Pfizer, Moderna, and Johnson &
Johnson vaccines.
(Reporting by Benoit Van Overstraeten;
Writing by Josephine Mason
Editing by Tom Hogue and Louise Heavens)
