New Sanofi GSK COVID vaccine shows good effectiveness

I thought that the Novavax COVID-19 vaccine would be the last one, but Sanofi and GSK will soon be seeking Emergency Use Authorization (EUA) for a new vaccine in the USA (and other countries). Although you might yawn at another COVID-19 vaccine, there are some good reasons to put this Sanofi-GSK version on your radar.

Since most of us have not thought much about other vaccines lately, this article will review this new vaccine, just so we are up to speed. And I guess I have to update my charts for COVID-19 vaccine myths and facts.

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What we know about the new Sanofi-GSK COVID-19 vaccine

The vaccine technology

The new Sanofi-GSK COVID-19 vaccine contains a 10µg antigen formulation of the SARS-CoV-2 adjuvanted recombinant protein-based containing the spike protein. It is not an mRNA vaccine, it’s more like traditional vaccines that contain an antigen to stimulate the adaptive immune system.

Sanofi and GSK had expected to seek authorization for their vaccine in 2021 but abandoned those plans after Phase 3 clinical trials showed disappointing results in older adults. They then developed a stronger version of the vaccine and tested it in new clinical trials, while also focusing on the vaccine’s utility as a booster.

Clinical trial

The Phase 3 clinical trial included 10,000 participants >18 years of age, randomized to receive two doses of 10µg vaccine or placebo at day 1 and day 22 across sites in the US, Asia, Africa, and Latin America.

The results, as reported by Sanofi, were:

  • 100% efficacy against severe COVID-19 disease and hospitalizations
  • 75% efficacy against moderate or severe COVID-19 disease
  • 57.9% efficacy against any symptomatic COVID-19 disease, which is somewhat lower than clinical trial results for the other vaccines. However, as I’ve said many times, don’t compare clinical trial results, and the clinical trial was done with numerous circulating variants as opposed to early clinical trials that were performed when there was only the original variant.
  • Sanofi reported a “favorable safety profile.” I will be checking it when the full application is submitted to the FDA.
  • Final analysis of the global booster trial confirms universal ability to boost neutralizing antibodies. Used as a booster dose after one of the other available coronavirus vaccines, the Sanofi-GSK shot increased antibody levels by 18- to 30-fold. 
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Again, this seems like just another COVID-19 vaccine, and you probably wonder if it is necessary, as it will be the sixth one in many countries.

There are two reasons why I think it’s still an important vaccine:

  1. For those individuals who think that mRNA vaccines are dangerous, they may be less reluctant to receive a more traditional vaccine like this new one from Sanofi-GSK. I know, most anti-vaxxers provide moving goalposts, so they’ll just invent some reason why this vaccine is bad, but it might convince some.
  2. The positive data that this vaccine can be a powerful booter for individuals who have gotten the mRNA and adenovirus vaccines.

It’s kind of amazing that just short of two years after the start of this pandemic, we have at least six vaccines that could be available to everyone. I did not think we would have one vaccine within this time period. I’m glad to be wrong about that.

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The Original Skeptical Raptor
Chief Executive Officer at SkepticalRaptor
Lifetime lover of science, especially biomedical research. Spent years in academics, business development, research, and traveling the world shilling for Big Pharma. I love sports, mostly college basketball and football, hockey, and baseball. I enjoy great food and intelligent conversation. And a delicious morning coffee!