Tonix Pharmaceuticals Submits New Drug Application For Fibromyalgia Treatment To U.S. FDA

Tonix Pharmaceuticals Holding Corp. has announced the submission of a New Drug Application (NDA) to the U.S. Food and Drug Administration (FDA) for TNX-102 SL (cyclobenzaprine HCl sublingual tablets) 5.6 mg. This non-opioid, centrally-acting analgesic demonstrated significant reductions in chronic, widespread pain associated with fibromyalgia in two Phase 3 studies and was overall well tolerated. The FDA granted TNX-102 SL Fast Track designation for fibromyalgia in July 2024, aimed at accelerating the evaluation of critical new drugs for severe conditions.

Seth Lederman, M.D., Chief Executive Officer of Tonix Pharmaceuticals, said in a statement, “With the submission of this NDA, Tonix has achieved a critical milestone in potentially bringing a new first-line treatment option to the large and dissatisfied fibromyalgia population that has not had a new pharmacotherapy in over 15 years. 

He also mentioned, “TNX-102 SL would be the first member of a new class of medicines for treating fibromyalgia. TNX-102 SL was designed and developed as a bedtime treatment to be taken daily on a chronic basis. Tonix believes bedtime TNX-102 SL relieves fibromyalgia pain by targeting the non-restorative sleep that is characteristic of fibromyalgia.”

The NDA is supported by data from two 14-week double-blind, randomised, placebo-controlled Phase 3 clinical trials that assessed the safety and efficacy of TNX-102 SL 5.6 mg as a nighttime treatment for fibromyalgia. The previous Phase 3 RELIEF trial, completed in December 2020, achieved its primary endpoint of significantly reducing daily pain compared to placebo (p=0.010). The confirmatory Phase 3 RESILIENT study, finished in December 2023, also met its specific primary endpoint with a significant reduction in daily pain (p=0.00005). 

Both trials showed that TNX-102 SL was, in general, well tolerated, with an adverse event profile similar to those of previous studies and no new safety signals. The most common treatment-related adverse event was tongue or mouth numbness, which was mild and self-limiting, rarely causing discontinuation (only one participant in each study).

Gregory Sullivan, M.D., Chief Medical Officer of Tonix Pharmaceuticals, stated, “Despite three FDA-approved medications, representing two different classes of medicines, there remains a need for new treatment options for fibromyalgia patients. If approved by FDA, TNX-102 SL would be the first of a new tricyclic class of medicines for treating fibromyalgia. The existing FDA-approved drugs for fibromyalgia include the gabapentinoid class, represented by Pfizer’s Lyrica® (pregabalin), approved in 2008, and the SNRI class, represented by Lilly’s Cymbalta® (duloxetine) and AbbVie’s Savella® (milnacipran) approved in 2007 and 2009, respectively. 

He further continued, “The TNX-102 SL tablet is based on a proprietary eutectic formulation of cyclobenzaprine HCl and mannitol that provides a stable product which dissolves rapidly and efficiently delivers cyclobenzaprine by the transmucosal route into the bloodstream. I would like to thank all the participants in our clinical trials and the trial investigators and staff, who worked together over many years to help make this important milestone possible.” 

Tonix believes the submitted data supports the NDA based on adequate safety and efficacy evidence from two well-controlled studies. The FDA has a 60-day filing review period to assess whether the NDA is complete and ready for review. If accepted, the Company anticipates a decision on approval in 2025 based on the Prescription Drug User Fee Act (PDUFA).