Sanofi and GSK signs LoI to develop an adjuvanted vaccine for COVID-19

Sanofi and GSK on Tuesday signed a letter of intent (LoI) to enter into a collaboration to develop an adjuvanted vaccine for COVID-19, using innovative technology from both companies, to help address the ongoing pandemic.

According to the LoI, Sanofi will contribute its S-protein COVID-19 antigen. The antigen is based on recombinant DNA technology. This technology has produced an exact genetic match to proteins found on the surface of the virus, and the DNA sequence encoding this antigen has been combined into the DNA of the baculovirus expression platform, the basis of Sanofi's licensed recombinant influenza product in the US.

GSK will contribute its proven pandemic adjuvant technology to the collaboration. The use of an adjuvant can be of particular importance in a pandemic situation since it may reduce the amount of vaccine protein required per dose, allowing more vaccine doses to be produced and therefore contributing to protecting more people.

"As the world faces this unprecedented global health crisis, it is clear that no one company can go it alone. That is why Sanofi is continuing to complement its expertise and resources with our peers, such as GSK, intending to create and supply sufficient quantities of vaccines that will help stop this virus," said Paul Hudson, CEO Sanofi.

"This collaboration brings two of the world's largest vaccines companies together. By combining our science and our technologies, we believe we can help accelerate the global effort to develop a vaccine to protect as many people as possible from COVID-19," said Emma Walmsley, CEO GSK.

Role of Antigen

The combination of a protein-based antigen together with an adjuvant is well-established and used in several vaccines available today.

Role of Adjuvant

An adjuvant is added to some vaccines to enhance the immune response and has been shown to create a stronger and longer-lasting immunity against infections than the vaccine alone. It can also improve the likelihood of delivering an effective vaccine that can be manufactured at scale.

Plan to initiate clinical trials

The two companies have plans to initiate phase I clinical trials in the second half of 2020 and, if successful and subject to regulatory considerations, aim to complete the development required for availability by the second half of 2021.

The new collaboration marks a significant milestone in Sanofi's and GSK's ongoing contributions to help fight COVID-19. The companies have entered into a Material Transfer Agreement to enable them to start working together immediately. Definitive terms of the collaboration are expected to be finalised over the next few weeks.