(Recasts, adds details, comments)
By Benoit Van Overstraeten
PARIS, Dec 15 (Reuters) - Sanofi and
GlaxoSmithKline said on Wednesday they expect data from
late-stage clinical trials of its booster dose of their COVID-19
vaccine candidate in the first quarter, instead of this year,
another delay for the potential shot.
The news came as the French and British partners said
preliminary data from trials showed the single-dose booster
provided strong immune responses.
The companies said they need more time to test the booster
on more people who have not been infected by the virus before
they can submit data to regulators.
The Phase III trial for the recombinant adjuvanted COVID-19
vaccine recruited most participants in the third quarter,
coinciding with a significant increase in the number of people
infected globally due to the Delta variant, it said.
"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.
This is the latest delay for the vaccine's development,
putting the companies further behind rivals in the race for
COVID-19 shots.
(For a Reuters' vaccine tracker graphic, see https://tmsnrt.rs/3GLZEWI)
They were forced to start a new clinical trial of the
vaccine candidate after trials last year showed an insufficient
immune response in older people.
In May, the companies had said the vaccine could be approved
by the year-end after initially targeting the first half of the
year.
Sanofi's shares in Paris were down 0.4%, while GSK in London
was down 0.3% by 0921 GMT.
Jefferies said the initial data was encouraging, but noted
the delay to the trial results.
"Vaccine sales would be almost entirely upside to current
(consensus), so no change to estimates likely, but success could
be a welcome boost to narrative," they said in a note.
The protein-based 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.
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 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.
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; Additional reporting by
Silvia Aloisi;
Writing by Josephine Mason
Editing by Tom Hogue and Louise Heavens)