Under the licensing deal, Sanofi Pasteur will fund all R&D, manufacturing and commercialisation, and will have exclusive worldwide marketing rights for the vaccine, whose target is undisclosed.
The companies began a $33m (€24m) collaboration focused on developing vaccines to protect against five pathogens in 2011, with CureVac meeting all the agreed milestones and Sanofi Pasteur now extending its exclusive and non-exclusive options.
Stabilising platform
CureVac uses an RNA-based platform to develop cancer immunotherapies and prophylactic vaccines under the name RNActive, as well as adjuvants based on non-coding RNAs (RNAdjuvant) for enhancing the immune response of other vaccines.
The German company told BioPharma-Reporter.com its platform overcomes the problem of unstable single-stranded RNA, by limiting their exposure to RNases (ribonucleases) without changing the amino acid sequence of the corresponding protein.
“Under physiological conditions and in the absence of RNases [ribonucleases] single-stranded RNA is inherently a very stable molecule,” said CureVac’s spokeswoman Verena Lauterbach.
“Our studies indicate that RNActive vaccines are rapidly taken up by cells, minimising the exposure to extracellular RNases. In addition, our RNActive vaccines have been optimised for increased stability and enhanced translatability using proprietary methods.”
Prize-winner
In March this year, CureVac won a €2m ($2.7m) inducement prize from the European Commission for RNActive vaccines’ resistance to extreme temperatures, a boon for developing countries.
mRNActive can be lyophilised (freeze-dried) or heated without damaging its biological activity. Sanofi Pasteur’s spokeswoman Julia Jara told us the company had been looking at the thermal-stability of vaccines for some time.
CureVac’s technology “could become game-changing for the vaccination field,” she said.
Production
CureVac’s spokeswoman told us the mRNA vaccine is produced in a scalable process enzymatically by transcription using unmodified nucleotides and a DNA template. “The RNA is then purified before formulation with a component to boost immunogenicity.”
She said CureVac had researched different delivery methods for the vaccine, but so far had not found a need to move away from standard intradermal injection, which allows the vaccine to be taken up by cells for translation of the encoded antigen.
As well as an upfront sum, CureVac will receive an additional payment for extending the option term for the other pathogens. It is also eligible for milestone payments up to €150m ($204m) and royalties from product sales.
RNA vaccines
RNA vaccines differ from classical vaccines by prompting the human body “to produce its own drug – we just deliver the ‘right message’ to the body,” said Lauterbach. Vaccine mRNA is taken up by immune cells and triggers an immune response against a coded antigen.
CureVac’s process delivers mRNA out of the natural four ribonucleotides “as building blocks,” she said. “Only the sequence of those nucleotides determines which antigen is used for vaccination whereas with classical vaccines you always have to produce an individual biological/recombinant product.”