Tonix Pharma Presents New Findings On TNX-801, Recombinant Horsepox, Live Virus Vaccine, At Vaccine Congress 2025 In Vienna

TNX-801 is up to 100,000-fold less virulent than live smallpox vaccine strains and a single dose provides robust immunogenicity and protection against mpox and rabbitpox (more than one year) in animals

Subcutaneous administration of TNX-801 yielded equivalent protection to the traditional percutaneous administration

CHATHAM, N.J., July 10, 2025 (GLOBE NEWSWIRE) -- Tonix Pharmaceuticals Holding Corp. (NASDAQ:TNXP), a fully integrated biopharmaceutical company with marketed products and a pipeline of development candidates, today announced the presentation of new findings on TNX-801 (recombinant horsepox, live virus vaccine) at the Vaccine Congress 2025 in Vienna on July 10, 2025, by Sina Bavari, PhD, Executive Vice President, Infectious Disease Research and Development.

TNX-801 is a recombinant horsepox-derived vaccine candidate designed to prevent orthopox viruses and provide durable humoral and cellular immunity from a single dose. In primary human dermal cells, the virus replicates twenty-seven to one-hundred-nineteen-fold less than licensed vaccinia strains, and in interferon receptor knockout mice it is up to one-hundred-thousand-fold less virulent than those legacy vaccines. Preclinical studies further showed that a single dose of TNX-801 produced strong binding and neutralizing antibody responses across mice, rabbits, hamsters, and cynomolgus macaques, including immunocompromised animals. All vaccinated macaques survived lethal Clade I mpox challenge without lesions, and rabbit models remained fully protected for fourteen months.

The World Health Organization and the Centers for Disease Control and Prevention continue to classify mpox as an ongoing public-health concern. A single-dose vaccine with the attenuation and immunogenicity profile demonstrated by TNX-801 could streamline outbreak response by reducing the need for approved multi-visit immunization schedules.