Sanofi Pasteur recently announced the development of a new mRNA vaccine for COVID-19. In February, Sanofi Pasteur announced that it would begin to develop a recombinant protein candidate vaccine for COVID-19.
David Loew, the global head of Sanofi Vaccines, said: “We are committed to using different approaches to solve the COVID-19 public health crisis by testing drugs and using two vaccines on different platforms. We believe that the more methods we explore, the more likely we are to successfully achieve this goal. Based on our experience in collaboration to date, we believe that the mRNA platform has the potential to help us meet the needs of vaccine development.”
The vaccine works by mimicking disease factors to stimulate the immune system and establishing a defense mechanism that remains active in the body against future infections. By providing nucleotide sequences that encode one or more antigens that have high potential to induce protective immune responses, mRNA vaccines provide an innovative approach for vaccine development strategy. mRNA vaccines also represent a potential innovative alternative to traditional vaccine methods as the high efficiency, the ability to start protein production without nuclear entry, the ability to develop rapidly, the potential for low-cost production, and the potential for safety management using non-viral vectors. This approach has the potential to develop vaccines for use in disease areas where vaccination is not feasible today. In addition, the required antigens or antigens can be expressed from mRNA without the need to adjust the production process to provide maximum flexibility and development efficiency.
Nucleic acid therapy has become a promising alternative to conventional vaccine methods. In 1990, in vitro transcription of mRNA successfully used in animals was reported for the first time. Reporter gene mRNAs were injected into mice and protein production was detected. Subsequent studies have found that the administration of vasopressin-encoded mRNA in the hypothalamus can cause physiological responses in rats. However, these early promising results did not attract significant investment in mRNA therapeutics, primarily because of the shortcomings of mRNA, such as instability, high innate immunogenicity, and inefficient in vivo delivery. But still, once these shortcomings are overcome, the use of mRNA has many beneficial features over subunit vaccines, killed or attenuated vaccines, as well as DNA-based vaccines.
Advantages of mRNA Vaccine
- Non-infectious and non-integrating. No potential risk of infection or insertional mutagenesis.
- In vivo half-life can be regulated via various modifications and delivery methods.
- The inherent immunogenicity of the mRNA can be down-modulated to further increase the safety profile.
- Various modifications can be done to make mRNA more stable and highly translatable.
- mRNA can be formulated into carriers to achieve efficient in vivo delivery.
- Capacity for low-cost and rapid scalable manufacture.