OSE Immunotherapeutics announced the online publication in BioRxiv of positive data from preclinical and human ex vivo studies with CoVepiT, its prophylactic vaccine program based on optimized peptides selected to induce a lasting sentinel T lymphocyte immune response against SARS-CoV-2, the virus that causes COVID-19, in barrier tissues such as the respiratory tract and the lung.

Nicolas Poirier, Chief Scientific Officer of OSE Immunotherapeutics, commented: “The CoVepiT program is based on a clinically-validated technology now shown to induce tissue-resident memory T lymphocytes (Trm) sentinel response against multiple parts of SARS-CoV-2, suggesting it provides a long-term protective immunity, as opposed to transient protection provided by neutralizing antibodies. In addition, this vaccine is designed to anticipate ongoing recurrent virus mutation and evolution, further adding to its long-term protective potential. T-cell epitopes were also selected based on the natural immunity observed against our peptides in convalescent COVID-19 patients. Generated using our Memopi vaccinal technology, which has already shown good tolerance and efficacy in a large number of cancer patients, these data build a strong basis to pursue the development of this 2nd generation of SARS-CoV-2 vaccine focused on memory CD8 T cell technology.”

Alexis Peyroles, Chief Executive Officer of OSE Immunotherapeutics, concluded: “We are rapidly advancing our fight against COVID-19, a major public health issue, with a vaccine program especially designed for people at risk, including older adults and immunocompromised populations. Initial preclinical results were strengthened by a parallel human ex-vivo study conducted in two clinical centers. We warmly thank Dr Didier Debieuvre, of the Hospital Center Emile Müller of Mulhouse and Dr Matthieu Le Flem of the Marine Firefighters of Marseille for their involvement and support in this study. Based on the positive data published today, we look forward to evaluating CoVepiT’s efficacy in a Phase 1 clinical study expected to be initiated by the end of 2020/early 2021.”

The article, entitled: “Tissue-resident memory CD8 T-cell responses elicited by single injection of a multi-target COVID-19 vaccine,” was published on BioRxiv, an open access preprint repository. It reports that:

CoVepiT showed strong induction of memory CD8 T lymphocytes against multiple SARS-CoV-2 proteins in vaccinated humanized mice. This validates the novel approach based on selected and optimized peptides (neoepitopes) improved using artificial intelligence algorithms to increase immunogenicity and better induction of memory T cells.

Humanized mouse model studies demonstrated a promising phenotype of Tissue-resident memory T cells (Trm) elicited after vaccination. These cells act as sentinels in barrier tissues and are well known to eliminate infected cells before significant virus replication.

Convalescent (asymptomatic, moderate, and severe) COVID-19 patients displayed strong memory T cells responses against our multi-target peptides, validating the potential for these peptides to naturally induce memory T cells responses.

Selection and generation of SARS-CoV-2 multi-target peptide vaccine (targeting Spike, M, N, and several non-structural proteins), covered for heterogeneity and already recurrent mutation, observed in up to 46,000 SARS-CoV-2 sequences isolated worldwide and for future virus evolution.

Further selection of peptides with high homology to previous endemic coronaviruses (particularly SARS-CoV-1 of 2002) anticipates future emergence of new coronaviruses.