Although they limit severe forms of the disease, Covid-19 vaccines do not prevent human-to-human transmission of the virus. When will we finally be able to move away from all the restrictions? A new French vaccine in the form of an oral spray looks set to meet this challenge!
A French team from the University of Tours has an innovative project. It is a vaccine against SARS-CoV-2 that blocks all transmissions from person to person. In the current context, where new and increasingly infectious variants are appearing regularly, could this vaccine finally end the pandemic? The French company LoValTech (for Loire Valley Technology), established in January 2022, has the exclusive license to exploit the patent for the new vaccine. Marketing authorization should be issued in late 2023 or early 2024.
A nasal vaccine that eliminates the risk of infection
Preclinical trials have been conducted in the laboratory with rodents (hamsters and mice). The vaccination protocol is as follows: two nasal sprays three weeks apart. The vaccine not only triggers an immune response but also neutralizes the virus which would eliminate the transmission of viruses between humans. The benefit is twofold. First, the virus stops spreading and infecting other people. Secondly, the virus circulates less and there is less risk of new variants emerging. Human clinical trials are expected to begin in the second quarter of 2022.
A vaccine that is effective against all variants?
The vaccine consists of viral proteins that are not subject to mutation. This means that the vaccine would be effective against all coronavirus variants beforehand! How is this possible? This vaccine triggers cellular immunity, not just humoral immunity. While other vaccines stimulate the production of antibodies (humoral immunity), this vaccine also activates T-lymphocytes (cellular immunity). The latest tests show that the vaccine is effective against the Delta variant of coronavirus. Regarding the Omicron variant, the research team is not yet in a position to comment, but preliminary results are encouraging.
And these are not the only benefits of this new type of vaccine! It consists of viral proteins and does not rely on mRNA technologies. Will it be able to convince the most reluctant to be vaccinated? Furthermore, it is easy to store: between 4 and 20 °C.
Although a large proportion of the population of the developed world will undoubtedly have already received their three doses of vaccine by the time of its release, this nasal vaccine could be an important new tool to fight the virus in developing countries.