Feb 23, 2022 - Health

Sanofi and GSK to seek authorization for COVID vaccine

Picture of two hands holding a syringe with the Sanofi and GSK logos in the background
Photo: Cezary Kowalski/SOPA Images/LightRocket via Getty Images

Sanofi and GSK on Wednesday said that their coronavirus vaccine has a 100% efficacy against severe infection and hospitalization in a phase 3 clinical trial.

State of play: The companies said early data indicated that their recombinant protein-based vaccine is 77% effective against symptomatic disease caused by the Delta variant. However, no specific data on the Omicron variant, the current dominant strain, was provided.

  • Other COVID vaccines are less effective against Omicron, although they still show strong efficacy against severe disease with a booster shot.

Details: The vaccine was found to be 75% effective against moderate infection and 57.9% effective against any symptomatic disease, according to the companies. They said that is "in line with expected vaccine effectiveness in today’s environment dominated by variants of concern."

  • When used as a booster for individuals who had already received an mRNA vaccine, the Sanofi-GSK vaccine "induced a significant increase in neutralizing antibodies of 18- to 30-fold across vaccine platforms and age groups."
  • After two doses and a booster shot of the vaccine, "neutralizing antibodies increased 84- to 153-fold compared to pre-boost levels."

What they're saying: "No other global Phase 3 efficacy study has been undertaken during this period with so many variants of concern, including Omicron, and these efficacy data are similar to the recent clinical data from authorized vaccines," said Thomas Triomphe, Sanofi's executive vice president.

What we're watching: Sanofi and GSK said they plan to ask for regulatory authorization from the Food and Drug Administration and the European Medical Agency once they have final results from a late-stage trial and another trial testing the vaccine as a booster that is set to be released “later this year.”

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