Tonix Pharmaceuticals (TNXP) Investor presentation summary

Historical context and scientific background

• Edward Jenner's 1798 work established the use of cowpox to prevent smallpox, with later evidence suggesting horsepox as a possible progenitor of vaccinia virus used in early vaccines.

• Genetic studies show horsepox is closely related to Jenner's vaccinia and early smallpox vaccines, with strong homology to 19th-century strains.

• Horsepox virus (HPXV) has more regulatory genes than 20th-century vaccinia, potentially conferring greater tolerability.

TNX-801: Synthetic horsepox vaccine development

• TNX-801 is a live, synthetic horsepox-based vaccine, genetically identical to the 1976 HPXV isolate.

• Demonstrates small plaque phenotype and reduced virulence compared to 20th-century vaccinia strains.

• Animal studies show TNX-801 provides robust protection against lethal monkeypox challenge with minimal reactogenicity.

• TNX-801 is well tolerated in immunocompromised mice and does not cause disseminated infection at high doses.

Efficacy and safety data

• In macaques, a single dose of TNX-801 resulted in 100% survival after lethal monkeypox challenge, with no observed lesions or clinical disease.

• TNX-801 vaccination led to minimal virus shedding, suggesting potential to reduce forward transmission.

• TNX-801 is 10- to 1,000-fold less virulent than traditional vaccinia vaccines in vitro and in vivo.

• Compared to Dryvax, TNX-801 showed improved tolerability in mice without sacrificing immune protection.