French pharmaceutical company Sanofi announced on Tuesday that it was discontinuing work on an mRNA vaccine against COVID-19 despite positive test results, citing a lag in progress in developing a coronavirus vaccine.
Instead, the mRNA technique will be used to develop vaccinations against other infections, including the flu.
The business said it would instead focus on another type of jab it is developing with British drugmaker GlaxoSmithKline and is nearing the end of human trials.
"The need is not to create new COVID-19 mRNA vaccines, but to equip France and Europe with an arsenal of messenger RNA vaccines for the next pandemic, for new pathologies," Sanofi's vice-president for vaccines, Thomas Triomphe said.
"There is no public health need for another messenger RNA vaccine" he added.
Sanofi's mRNA vaccine, which uses the same technology as rivals Pfizer-BioNTech and Moderna, achieved positive results in phase one and two clinical studies, according to the company.
Sanofi has indicated that it would not go to the third and final phase, claiming that it will be too late to market with 12 billion COVID-19 doses planned to be manufactured by the end of the year.
The results of the other vaccine developed in collaboration with GlaxoSmithKline are expected by the end of 2021.
The companies are combining a Sanofi-developed antigen that stimulates the generation of germ-killing antibodies with GSK's adjuvant technology, which is a substance that boosts the immune response elicited by a vaccine.
Messenger RNA trains the immune system to recognize the real virus by sending genetic instructions to human cells to generate a coronavirus surface protein.
Initial results for the mRNA product showed that 91% to 100% of test participants produced antibodies two weeks following a second injection, according to Sanofi.
There were no side effects, and the vaccine's tolerance was equivalent to that of other mRNA vaccines developed by Pfizer-BioNTech and Moderna.
Triomphe said the immunological response to the Sanofi mRNA vaccination is "strong."
Sanofi has already begun developing new testing for a seasonal flu vaccine, with clinical trials set to begin next year.
The results of the mRNA vaccine "will clearly help inform the path forward for our mRNA development programs," Sanofi's global head of research and development, Jean-Francois Toussaint said.
BioNTech, a German company that collaborated with Pfizer to develop a coronavirus mRNA vaccine, said in July that it would begin testing a malaria vaccine based on mRNA technology.
