Sanofi, GSK variant-specific shot ‘effective against Omicron’

This Feb 4, 2022 picture shows in a reflection the new logo of French pharmaceutical group Sanofi which is presented on the day of the group's 2021 full year results at Sanofi headquarters in Paris. (ERIC PIERMONT / AFP)

PARIS/LONDON – Late-stage data on an experimental COVID-19 vaccine from Sanofi and GSK has showed the shot confers protection against the Omicron variant of the virus, the companies said on Friday. 

The so-called bivalent vaccine targets the Beta variant – first identified in South Africa – as well as the original strain of the virus. 

READ MORE: WHO panel backs Omicron-adapted vaccine as booster dose

In a trial involving 13,000 adults, the vaccine demonstrated an efficacy rate of 64.7 percent against symptomatic COVID, and 72 percent efficacy against infections specifically caused by the Omicron variant. 

Sanofi-GSK’s vaccine is the first candidate to demonstrate efficacy in a placebo-controlled trial in an environment of high Omicron variant circulation.


When used in people who previously had COVID, the results were stronger. The vaccine generated an efficacy rate of 75.1 percent against symptomatic COVID and 93.2 percent in Omicron-confirmed symptomatic cases, the companies said. 

"Sanofi-GSK’s vaccine is the first candidate to demonstrate efficacy in a placebo-controlled trial in an environment of high Omicron variant circulation," Sanofi said in a statement. 

Sanofi's Paris-listed shares and GSK's London-listed shares were both up more than 1 percent in morning trading. 

Earlier this month, the bivalent vaccine showed potential in two trials to protect against the virus' main variants of concern – the Omicron BA.1 and BA.2 strains – when used as a booster shot. 

Sanofi and GSK, two of the world's biggest vaccine makers, are hoping to gain a foothold in the market for next-generation variant-focused COVID shots, after falling behind competitors including Moderna, AstraZeneca and Pfizer-BioNTech, in the original race to contain the pandemic. 

The new data supporting the bivalent vaccine will be submitted to regulatory authorities with the hope of making the shot available later this year, the companies said on Friday. 

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Sanofi and GSK's original COVID vaccine is already under review by the European Medicines Agency. 

The companies have bet that this bivalent vaccine molded on the now-supplanted Beta variant will confer broad protection against future viral strains on the basis that Beta expresses similar mutations across multiple variants of concern, including Omicron.