Covid-19: what is the status of the Institut Pasteur nasal vaccine?

The results of the preclinical trials concerning the lentiviral vaccine candidate, which can be administered by the nasal route, were recently published. According to the Institut Pasteur, it is effective on animals.

While the foundation announced at the beginning of the week the end of one of its three vaccine projects, it remains strongly mobilized to fight against the coronavirus epidemic. She has been working from the start on a vaccine that can be administered by the nasal route, the work of which was published in pre-print on BioRxiv last July. Its vaccine candidate uses a lentiviral vector, ie it allows the introduction of the therapeutic gene into cells, “at the gateway to the virus”, Namely the nose, throat, mouth, larynx and trachea. The results of the study, conducted on two animal models, indicate that the cellular response is abundant: “Vaccination by the nasal route with this vector drastically reduces the viral load in the lungs and prevents pathogenic pulmonary inflammation”, Indicates the Pasteur Institute, in its press release of January 19. The vaccine is therefore effective in two models of‘animals, by attracting’ elements of the protective immune response directly to the upper respiratory tract”.

The mice, the first model on which this nasal vaccine from the Institut Pasteur is tested, triggered very high antibody titers in their serum. Moreover, using another methodology, “> 1000-fold decrease in lung viral load”Was observed, allowing to block the inflammation of the lungs, but also the cytokine storm. These results are also confirmed in the hamster, whose effectiveness of the vaccine has been demonstrated by a very strong protection and a notable decrease in the pulmonary viral load. Research and studies are continuing; it remains to be determined how long this protection will last. However, the results are already encouraging, as indicated by Pierre Charneau, Head of the Molecular Virology and Vaccinology Unit at the Institut Pasteur: “Lentiviral vector emerges as a promising vaccine candidate for nasal administration to induce near-sterilizing mucosal immunity in two highly sensitive preclinical animal models “.