Tonix Pharmaceuticals (NASDAQ:TNXP) said it is advancing development plans for TNX-4800, a long-acting human monoclonal antibody designed for the prevention of seasonal Lyme disease, as the company prepares for regulatory discussions on potential late-stage clinical pathways.
The company said it plans to hold a meeting with the U.S. Food and Drug Administration in 2026 to explore Phase 2/3 development options.
These include the possible use of a controlled human infection model, or CHIM, as well as an adaptive Phase 2/3 field study design.
Tonix said it expects good manufacturing practice-grade investigational product for TNX-4800 to be available for clinical testing in early 2027.
The antibody targets outer surface protein A (OspA), a key antigen expressed by Borrelia burgdorferi, the bacterium responsible for Lyme disease.
The company estimates that roughly 70 million people in Lyme-endemic areas of the United States could potentially benefit from seasonal prophylaxis.
Tonix noted that there are currently no FDA-approved vaccines or preventive treatments on the market for Lyme disease.
According to the company, TNX-4800 is designed to provide near-immediate immunity following a single subcutaneous dose, offering seasonal protection during periods of high tick exposure.
Tonix said the program reflects its broader strategy of developing biologics for infectious diseases with significant unmet medical need.