Sanofi ditches mRNA Covid-19 vaccine after rivals’ success


Sanofi is dropping plans for its own mRNA-based Covid-19 vaccine because of the dominance achieved by BioNTech-Pfizer and Moderna in using the technology to fight the pandemic, the company said.

The move highlights the challenges of competing in particular with pioneer BioNTech, which rose from obscurity through its alliance with pharma major Pfizer last year. They have delivered close to 1.5bn doses so far to become the Western world’s largest Covid-19 vaccine maker.

French healthcare group Sanofi will instead focus on efforts with British partner GlaxoSmithKline to bring another Covid-19 vaccine candidate to market based on the more conventional protein-based approach, where mass trials are ongoing.

The decision to drop clinical development of a shot based on mRNA, or messenger RNA, acquired as part of its takeover of Translate Bio, came despite positive phase one and two study interim results announced yesterday, where participants’ blood readings showed a strong immune reaction.

But Sanofi said the read-out encouraged it only to pursue the technology as a potential vaccine against influenza and other diseases, giving up on the area of Covid-19 because of the strong market presence of the two approved mRNA shots.

“The results are extremely important as they show us that the platform we acquired works,” said Thomas Triomphe, head of the Sanofi Pasteur vaccines division. He said kicking off final phase three trials now made no sense.

Would it, responsibly, be the best use of this wealth of science afforded by mRNA vaccines to make a Covid-19 vaccine and try and bring another mRNA Covid-19 vaccine to people who already today may not want an mRNA Covid-19 vaccine? Clearly not.” 

Mr Triomphe also dismissed the prospect for annual repeat shots, which has been intensely debated by researchers and pharmaceutical executives, with clear trial results on the need for yearly boosters still to come.

US regulators cleared a third Pfizer-BioNTech shot half a year after the initial two-shot course for some at-risk groups and Moderna aims to follow suit.

Mr Triomphe said that given evidence of virus-fighting antibodies surging after a third shot, a recurring market was out of the question. 

“With a fourth dose you’d have extremely high antibodies and you absolutely would not need an annual Covid-19 vaccine.”