When drugmakers geared up to respond to the pandemic, Sanofi and GSK, as two of the largest vaccine makers, were expected to make a major contribution. Protein-based vaccines, which use a synthetic version of the coronavirus’ “spike” protein to stimulate an immune response, are an older, more familiar technology than mRNA. The manufacturing and distribution infrastructure for them are also well-established.
Yet the first version of the Sanofi-GSK vaccine didn’t live up to expectations, forcing the companies to turn to a second formulation that they advanced into a late-stage study of more than 37,000 volunteers. With more than half the world’s population yet to be fully vaccinated, and the likelihood booster shots will be needed, their vaccine could yet play an important role.
Parallel to its work in protein vaccines, Sanofi had added a coronavirus project to its long-standing mRNA vaccine partnership with Translate Bio. The company then expanded its overall investment in mRNA by launching a research “center of excellence.” Those moves culminated in an acquisition of Translate in August.
The vaccine from the mRNA partnership did raise antibodies against the coronavirus. Three weeks after the second of two doses, antibody levels had increased at least fourfold from baseline in nearly all of the patients tested, and the shot had the same safety and tolerability profile as other mRNA vaccines, Sanofi said.
Nonetheless, the wide availability of mRNA vaccines from Pfizer and Moderna, a spokesperson said, mean “it does not make sense” to advance that product.
Sanofi sees more promise for mRNA in fighting influenza. The company has already conducted Phase 1 trials of two formulations targeting a single strain, A/H3N2, and is hoping to expand that work in 2022.
Sanofi won’t be alone in that quest. Moderna began Phase 1 work in July and Pfizer started its first tests Monday.
Of the three companies, only Sanofi is an established name in flu vaccines, with its shots bringing in 2.5 billion euros, or about $2.9 billion, in 2020. Pfizer has a vaccines business too, and its pneumococcal vaccine franchise Prevnar is one of the largest-selling pharmaceutical products in the world.