Tonix Pharmaceuticals Holding Corp. 8-K

What Happened
On May 15, 2026, Tonix Pharmaceuticals (TNXP) filed an 8-K under Regulation FD reporting Phase 1 pharmacokinetic (PK) data for its TNX-4800 Lyme disease candidate and presented the data at the Global Lyme Alliance. The company attached the presentation as Exhibit 99.01. Tonix also presented simulations predicting that a two-dose 350 mg subcutaneous regimen (Day 1 and Day 56) would maintain mean serum levels above a Minimum Effective Concentration (MEC) of 10 µg/mL for roughly six months, the proposed primary endpoint for a planned adaptive Phase 2 field study.

Key Details

• Dosing simulated: two 350 mg subcutaneous doses on Day 1 and Day 56.
• Predicted mean days to fall below MECs: 10 µg/mL = 196 days; 15 µg/mL = 161 days; 20 µg/mL = 136 days; 5 µg/mL = 265 days.
• Planned next step: an adaptive Phase 2 field study targeted for the first half of 2027, pending agreement with the U.S. Food and Drug Administration.
• Disclosure type: Regulation FD / Other Events; presentation attached as Exhibit 99.01 to the 8-K.

Why It Matters
These PK simulations support the feasibility of a two-dose regimen that could meet the company’s proposed primary endpoint (maintaining mean serum levels above 10 µg/mL for six months), which is a key design element for the planned Phase 2 field study. For investors, the filing signals advancement of TNX-4800’s development plan and clearer timing toward Phase 2 (H1 2027 subject to FDA agreement). The information is predictive and subject to regulatory review and clinical outcomes; Tonix’s filing includes standard forward-looking statement cautions and does not report clinical efficacy or financial results in this 8-K.