Sanofi drops mRNA COVID vaccine candidate amid success of rivals
French healthcare group Sanofi has announced that it is dropping plans for its mRNA COVID vaccine due to the success of Pfizer/BioNTech’s and Moderna’s own vaccines.
Sanofi will instead focus on efforts with British partner GlaxoSmithKline to bring a COVID-19 vaccine candidate to market based on the more conventional protein-based approach, where mass trials are ongoing.
The late-stage human trial for their recombinant COVID-19 vaccine candidate was launched in May this year, with the aim of gaining approval by the end of 2021.
The decision to drop clinical development of the mRNA vaccine, acquired as part of its takeover of Translate Bio, came despite positive Phase I/II study interim results announced on Tuesday, where participants’ blood readings showed a strong immune reaction.
The initial data from the study showed neutralising antibody seroconversion (defined as 4-fold increase vs baseline) in 91% to 100% of study participants, two weeks after a second injection, across all three dosages tested. Also, no safety concerns were observed and the tolerability profile is comparable to that of other unmodified mRNA COVID-19 vaccines.
Jean-Francois Toussaint, global head of research and development at Sanofi Pasteur 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.
He said: “We are happy to see those positive initial results. We have made an impressive move just nine months after the worldwide proof of concept of mRNA vaccines and only 17 since we started this first mRNA vaccine project.
“These results will clearly help inform the path forward for our mRNA development programs. Today, we have a promising mRNA platform, which we’re taking to the next level in development, including moving to modified mRNA, and against other diseases, including flu.”
Targeting 2022 initiation of its clinical studies for an influenza vaccine with modified mRNA, Sanofi launched a Phase I clinical trial in June 2021 evaluating an mRNA-based investigational vaccine against seasonal influenza. The trial will evaluate the safety and immunogenicity of a monovalent flu vaccine candidate coding for the hemagglutinin protein of the A/H3N2 strain of the influenza virus across two formulations (MRT5400 and MRT5401) with different lipid nanoparticles.