Tonix Pharmaceuticals In-Licenses Phase 2/3-Ready Monoclonal Antibody TNX-4800 For Seasonal Prevention Of Lyme Disease

Tonix Pharmaceuticals Holding Corp., a fully integrated biopharmaceutical company with marketed products and a broad development pipeline, has announced that it has secured worldwide rights to TNX-4800 (formerly known as mAb 2217LS). TNX-4800 is a long-acting human monoclonal antibody designed to target the outer surface protein A (OspA) of “Borrelia burgdorferi”, the bacterium responsible for Lyme disease. Developed by researchers at UMass Chan Medical School, the antibody is licensed to Tonix and is intended for seasonal, preventive use. 

Administered as a single subcutaneous dose in the Spring, TNX-4800 is designed to provide protection against Lyme disease throughout the Fall, covering the full tick season in the United States. There are currently no FDA-approved vaccines or prophylactic treatments available to prevent Lyme disease. Seth Lederman, M.D., Chief Executive Officer of Tonix Pharmaceuticals, noted that Lyme disease remains the most common vector-borne infection in the United States, with cases increasing annually. He said the licensing of TNX-4800 strengthens Tonix’s infectious disease pipeline by offering a potentially unique, single-dose approach that can provide protection within two days of administration and maintain coverage throughout the season. 

Lederman emphasized that the antibody’s innovative mechanism—blocking the maturation of “Borrelia” in the midgut of infected ticks—aligns with Tonix’s commitment to developing groundbreaking solutions. He added that the company looks forward to advancing the TNX-4800 program toward further clinical evaluation. Mark Klempner, M.D., Professor of Medicine at UMass Chan Medical School and leader of the research team that developed mAb 2217LS, stressed the importance of this program in addressing a growing public health concern. 

He highlighted that more than 30 years of clinical experience support the safe and effective use of monoclonal antibodies for preventing infections. Klempner said TNX-4800’s ability to provide immediate immunity through a single dose makes it distinct from vaccine programs currently in development. Terence R. Flotte, M.D., Provost, Dean, and Executive Deputy Vice Chancellor of UMass Chan Medical School, expressed pride in partnering with Tonix. He stated that this collaboration underscores UMass Chan’s dedication to advancing translational research that addresses unmet medical needs. 

Flotte added that TNX-4800 has the potential to protect vulnerable populations from Lyme disease and reflects both institutions’ shared commitment to science-driven solutions for urgent health challenges. TNX-4800 is a fully human monoclonal antibody with an engineered extended half-life that binds to OspA on “Borrelia” bacteria, thereby preventing the bacterium’s maturation in infected deer ticks. The antibody was developed through amino acid modifications to extend its serum half-life, ensuring durable protection. 

By delivering antibodies directly rather than relying on the body’s immune system to produce them, TNX-4800 offers pre-exposure prophylaxis without the need for multiple doses or the risks previously associated with Lyme vaccines. Preclinical studies have shown that TNX-4800 effectively blocks the transmission of major “Borrelia” genospecies from ticks to animals. 

Tonix plans to advance TNX-4800 into further clinical trials with the goal of submitting a Biologics License Application (BLA) to the U.S. Food and Drug Administration. This agreement highlights Tonix’s strategic expansion into infectious diseases and reflects ongoing efforts to develop innovative and reliable approaches to protect against Lyme disease for the millions of people living, working, or vacationing in endemic areas.