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Sanofi will not go to phase 3 of trials for its messenger RNA vaccine against Covid-19, the last step before marketing. The laboratory said Tuesday that it would continue the development of its other vaccine, recombinant protein, against the virus.

It was expected – late – after those of Pfizer-BioNTech, Moderna and Johnson & Johnson: the messenger RNA vaccine against the Covid-19 from Sanofi will not finally see the light of day, the laboratory having explained Tuesday, September 28 that it does not ‘would not go to phase 3 of trials, the last step before marketing.

Despite positive intermediate results for phase 1-2 of the trial of its messenger RNA vaccine, Sanofi believes that it would arrive too late on the market, while 12 billion doses of anti-Covid vaccines will have been produced in the total by the end of the year.

The results of phase 3 on its other vaccine, based on a recombinant protein and developed with the British GSK, are still expected before the end of 2021.

Initial data from the messenger RNA technology trial shows seroconversion, that is, the production of antibodies, in 91% to 100% of participants two weeks after the second injection, indicates Sanofi.

>> To read: Messenger RNA, the innovative technology behind Pfizer and Moderna’s vaccines against Covid-19

These positive results are verified for the three assays which were tested.

In addition, no side effects were observed and the safety profile is comparable to that of other Covid-19 RNA vaccines, such as those developed by the German-American tandem Pfizer-BioNTech and by the American biotech Moderna.

“No public health need to have another messenger RNA vaccine”

With this technology, the laboratory wanted to assess the ability to elicit an immune response. “However, it is strong,” commented to AFP Thomas Triomphe, vice-president of the vaccines branch of Sanofi.

Sanofi had been working with Translate Bio on this vaccine since March 2020, and even bought this American biotech in early August for some 2.7 billion euros.

However, “the need is not to create new Covid-19 RNA vaccines, but to equip France and Europe with an arsenal of messenger RNA vaccines for a next pandemic, for new pathologies”, adds Thomas Triomphe.

Therefore, Sanofi will not develop phase 3 for this vaccine, because “there is no public health need to have another messenger RNA vaccine”, he continues.

>> To read: Anti-Covid-19 vaccines: Pasteur and Sanofi, symbols of the decline in French research?

Sanofi, on the other hand, says it wants to develop vaccines with this technology against other viruses, without side effects and with fewer constraints in terms of storage temperature.

The group has already launched initial trials for a monovalent vaccine – with a single strain of virus – against seasonal influenza. He indicated on Tuesday that he wanted to launch clinical trials against influenza next year, this time with a quadrivalent vaccine.

With AFP

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