> ## Content Index
> Fetch the complete content index at: https://www.fdaweb.com/llms.txt
> Use this file to discover other available public pages before exploring further.

# FDA, Tonix Align on Lyme Disease Prevention Phase 2 Study
- URL: https://www.fdaweb.com/fda-tonix-align-on-lyme-disease-prevention-phase-2-study/
- Published: 2026-08-05T12:00:00.000Z
- Updated: 2026-09-14T13:44:32.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5161581

Minutes of a Type C meeting between FDA and Tonix Pharmaceuticals show the agency and company aligned on the protocol for an adaptive Phase 2 study of Tonix’ TNX-4800 (human anti-outer-surface protein A monoclonal antibody) to prevent Lyme disease in adults. A company [statement](https://www.globenewswire.com/news-release/2026/08/03/3337366/0/en/Tonix-Pharmaceuticals-Announces-Positive-Minutes-from-Type-C-FDA-Meeting-to-Discuss-Adaptive-Phase-2-Field-Study-of-TNX-4800-a-Human-anti-OspA-Monoclonal-Antibody-to-Prevent-Lyme-D.html?ref=fdaweb.com) says the adaptive field study will enroll about 3,300 adults over two Lyme disease seasons.

The primary efficacy endpoint will be Lyme disease prevention through six months after the first dose, and a key secondary efficacy endpoint of prevention through three months.

TNX-4800 is described as a long-acting bactericidal, human monoclonal antibody with an engineered extended half-life that targets the outer-surface protein A on *Borrelia* bacteria. When TNX-4800-containing blood is ingested by the tick, the company says, it either kills or blocks the maturation of *Borrelia burgdorferi* in the mid-gut of infected deer ticks.