Sanofi has reported findings from two clinical trials, VAT02 Cohort 2 and COVIBOOST VAT013, where its new next-generation Covid-19 booster vaccine candidate provided robust immune response against variants of concern, including Omicron .

This booster vaccine is modelled on the Beta variant antigen and comprises a pandemic adjuvant of GlaxoSmithKline (GSK).

According to the data from the Phase III VAT02 Cohort 2 trial, the vaccine induced a substantial boost in antibody titers above baseline against various variants of concern at day 15 after vaccination in adult subjects who priorly received mRNA Covid-19 vaccines.

The vaccine offered a 15-fold, 30-fold and 40-fold rise in antibody titers against D614 parent virus, Beta strain and Omicron BA.1, respectively.

Furthermore, the latest booster vaccine generated double the number of neutralising antibodies against Omicron BA.1 and BA.2 versus the D614-based booster.

Carried out by the Assistance Publique – Hôpitaux de Paris (AP-HP), the COVIBOOST trial is a randomised, single-blinded, multicentre trial.

Findings showed that following initial vaccination with two doses of Pfizer-BioNTech’s Comirnaty Covid-19 vaccine, the Sanofi-GSK next-generation booster candidate elicited an immune response greater than the Pfizer-BioNTech’s booster or Sanofi-GSK’s first-generation booster.

Pfizer-BioNTech’s booster or Sanofi-GSK’s first-generation booster act on the original D614 parent strain.

In addition, 76.1% of the subjects who received the Sanofi-GSK next-generation booster had a minimum of a ten-fold rise in neutralising antibody titers for the original D614 SARS-CoV-2 strain between days 0 and 15.

This next-generation vaccine also elicited enhanced responses against the Omicron BA.1 variant compared to the two other vaccines.

Across both trials, the next-generation vaccine candidate was found to be well-tolerated with a favourable safety profile.

Sanofi Vaccines executive vice-president Thomas Triomphe said: “The Beta variant expresses similar mutations across multiple variants of concern, including Omicron, making it a strong vaccine candidate to confer broad protection against multiple strains of Covid-19.

“Seeing the cross-neutralisation data from the independent AP-HP study, we believe this next-generation booster could have an important role to play for public health vaccination campaigns.”