disappointing results in older adults. So the companies then developed a stronger version of the vaccine and tested it in new trials, according to the New York Times.
In laboratory studies, two doses of the Sanofi-GSK vaccine stimulated the production of more neutralizing antibodies than an approved mRNA vaccine, the companies noted.
The data have not yet been published.
The Sanofi-GSK vaccine uses a slightly modified version of the protein itself to stimulate an immune response, a commonly used method of making vaccines.
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Protein vaccines are relatively inexpensive and may not require the ultra-cold storage needed for mRNA vaccines, which may make protein-based vaccines more likely to be used in Africa, where there are low vaccination rates, the Times reports.
Last month, Novovax applied to the U.S. Food and Drug Administration for emergency authorization of a similar protein-based COVID-19 vaccine.
The vaccine was safe and well-tolerated by adults of all ages, according to the companies. They said they plan to submit the vaccine for emergency authorization to regulatory authorities in the United States and Europe.
For the latest information on COVID vaccines, visit the CDC.