Preclinical results indicate robust antibody activity against tuberculosis and antimicrobial resistant virus strains

Data presented at The Union World Conference on Lung Health 2023

BETHESDA, MD & GAITHERSBURG, MD, USA I November 15, 2023 ILonghorn Vaccines and Diagnostics, a One Health company developing vaccines and diagnostic tools for global public health and zoonosis concerns, today presented new data from an animal study of LHNVD-301, the company’s lead tuberculosis vaccine candidate. The data showed that a mycobacterium tuberculosis (MTB) vaccine could generate broader protection against other pathogens susceptible to antimicrobial resistance (AMR). The study was presented at The Union World Conference on Lung Health 2023, which is taking place in Paris on November 15-18, 2023.

LHNVD-301 is an unconjugated, peptide-based vaccine that combines a MTB heat shock protein epitope and a peptidoglycan (PGN) epitope. PGN is a cell wall component of bacteria that plays an important role in infections. The combination of heat shock protein and PGN generates broad reactive antibodies. It represents a novel approach that combats AMR, while targeting tuberculosis by combining multiple epitopes specific to MTB and common to gram-positive bacteria into a peptide vaccine.

“AMR is a global threat to public health, and MTB is one of the highest priority viruses among drug-resistant strains that contributes to AMR,” said Longhorn CEO Gerald W. Fischer, MD. “Longhorn’s mission is to combat pandemics and infectious diseases that pose a large public health issue with broad based vaccines. We are developing LHNVD-301 to address MTB as a global threat and combat AMR. Unconjugated peptides targeting epitopes of multiple pathogens enable a cost-effective, easily scalable approach for vaccine development, which is crucial for covering those most at risk for TB. We look forward to further investigating the safety and efficacy of LHNVD-301.”

Results of the study, “Unconjugated Peptides Comprising Mycobacterium tuberculosis Heat Shock Protein and Staphylococcus aureus Peptidoglycan Generate Broadly Reactive Antibodies to Gram-positive Bacteria,” include:

  • Robust and broad IgG1 antibodies were induced to both PGN and TB Pep01, and demonstrated higher titers with 10 and 20 µg doses, compared to 1 µg dose.
  • Unconjugated peptides comprising MTB HSP16.3 and PGN from SA generated broadly reactive antibodies to fixed and live mycobacteria, staphylococci, streptococci, and bacilli.
  • Combining MTB-specific epitopes with common epitopes among gram-positive bacteria could be a useful strategy for mitigating the global threat of AMR and provide novel treatment options for tuberculosis.

ICR mice were immunized with 1, 10, and 20 µg of TB Pep01 and ultrapure PGN, formulated with AddaVax™ adjuvant. Serum IgG1 titers to TB Pep01, PGN, and various gram-positive bacteria including MTB were analyzed by indirect fixed ELISA. Titers to Mycobacterium smegmatis, Staphylococcus epidermidis, Staphylococcus aureus, Bacillus subtilis and Group B Streptococcus were also assessed using live bacteria by an enzyme-linked immunosorbent assay, known as ELISA.

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About Longhorn Vaccines and Diagnostics

Longhorn Vaccines and Diagnostics LLC is a closely held One Health company based in Maryland that is developing broad coverage vaccines and diagnostic tools for worldwide public health concerns and to prevent future pandemics. Since its inception in 2006, Longhorn has focused on developing broad coverage vaccines and diagnostic tools that can impact a pandemic on a global scale and at all socio-economic levels. Since pandemics flow between humans and animals, Longhorn caters to both in order to surveil, diagnose, prevent and treat the next infectious disease.

Longhorn developed and patented a composite peptide platform for generating vaccines against challenging pathogens, multiple pathogens, and engineering multiple targets for preventing the effects of a disease. LHNVD-105, an adjuvated universal influenza vaccine targeting NA, M1, M2, M2e, HA head and HA stalk, is Longhorn’s lead vaccine candidate. An IND-enabling stage vaccine, LHNVD-105 is expected to enter phase I clinical trials in Q2/Q3 2024. Longhorn has multiple vaccines and monoclonal antibody candidates in pre-clinical testing for viral and respiratory diseases.

SOURCE: Longhorn Vaccines and Diagnostics