Tonix Stock Plunges 13.81% on FDA Approval Despite $230M Volume Surge Ranking 430th

On August 15, 2025, Tonix Pharmaceuticals (TNXP) saw a 13.81% decline in its stock price despite a 72.35% surge in trading volume to $0.23 billion, ranking 430th in market activity. The drop came amid the company’s announcement of U.S. Food and Drug Administration (FDA) approval for Tonmya (cyclobenzaprine HCl sublingual tablets) as a treatment for fibromyalgia in adults. The drug, previously known as TNX-102 SL, is expected to launch in the U.S. by the end of 2025.

The FDA’s decision followed positive results from two double-blind, randomized, placebo-controlled Phase 3 trials involving 1,000 patients. Tonmya demonstrated significant reductions in daily pain scores over 14 weeks, the primary endpoint. Additionally, a higher proportion of patients experienced a clinically meaningful improvement in pain compared to placebo. Across three trials with over 1,400 participants, the drug was generally well tolerated, with common adverse effects including oral hypoesthesia, dry mouth, and fatigue.

Tonix emphasized that Tonmya is contraindicated for patients with hypersensitivity to cyclobenzaprine, those using monoamine oxidase inhibitors, or individuals with cardiac conditions. The company will host a webcast and conference call on August 18 to discuss the approval and its implications for the fibromyalgia market.

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