BETHESDA, Md. & GAITHERSBURG, Md.– Longhorn Vaccines and Diagnostics LLC, a One Health and One World company developing vaccines and diagnostic tools for global public health and zoonosis concerns, reported data today from a pre-clinical study of an adjuvanted composite peptide vaccine comprised of various conserved epitopes from both influenza and coronavirus. The data was consistent with Longhorn’s lead vaccine candidate LHNVD-105, a composite peptide universal influenza vaccine candidate, delivered with the US Army’s Liposomal Adjuvant (ALFQ). Both vaccines generate a robust, durable and balanced immune response.
The findings from this study were presented in an oral presentation session at Infectious Disease Week (IDWeek) 2022, taking place in Washington, DC, Oct. 19-23, 2022.
“Adjuvanted composite peptides are a powerful vaccine platform that can be used for single or multiple pathogens and are easily scalable and cost-effective,” said Longhorn CEO Gerald Fischer, MD. “The study data support the potential for Longhorn to develop vaccines against a wide range of pathogens – separately and in combinations – using many different adjuvants with consistent results. We aim to move our universal influenza vaccine candidate, LHNVD-105, into Phase 1 clinical trials starting in 2023. Our team is committed to developing vaccines that will have impact around the world.”
The presentation, titled, “A Composite Peptide Vaccine Comprised of Conserved SARS-CoV-2 and Influenza Epitopes Generated Antisera Reponses to Both Coronavirus and Influenza,” showed:
- Immunization of mice with composite peptide vaccines comprised of conserved epitopes of either SARS-CoV-2 RNA polymerase or Spike protein, each including conserved Influenza (NA and M2e) epitopes and a T cell epitope, generated cross-reactive and durable neutralizing antibodies to each of the coronavirus and influenza epitopes in the vaccine.
- The combined composite peptide vaccine generated highly enhanced immune responses with only primary immunization, which increased further with a boost (titers up to 100,000).
- Th1 and Th2 responses were observed (IgG1 and IgG2b titers) and the titers remained steady for beyond 250 days post primary immunization, without additional boosts post day-35, indicating the width and durability of immune responses.
“Durable and effective universal and combination vaccines will be essential to overcoming vaccine fatigue and reducing cost of vaccine administration across the world” said Longhorn President Jeff Fischer. “The data presented today strengthens the case for adjuvated composite peptide vaccines for reducing viral, bacterial, and parasitic infections and validates our approach of using multiple conserved targets on each pathogen to reduce the likelihood of escape mutations.”
