FDA accepts Tonix's NDA for non-opioid fibromyalgia drug TNX-102 SL

Tonix Pharmaceuticals Holding Corp. (Nasdaq: TNXP) announced that the US Food and Drug Administration (FDA) has accepted its New Drug Application (NDA) for TNX-102 SL, a non-opioid, centrally acting analgesic designed for fibromyalgia management.

The FDA is expected to assign a Prescription Drug User Fee Act (PDUFA) target action date in its Day 74 Letter, where it will also confirm whether Priority Review has been granted.

The acceptance of the NDA marks a significant milestone, as TNX-102 SL has the potential to become the first new drug for fibromyalgia in over 15 years.

The drug could also represent the first member of a new class of analgesics for managing the condition.

Fibromyalgia and unmet medical needs

Fibromyalgia affects over 10 million adults in the United States, with women being disproportionately impacted.

Despite its prevalence, there have been no new treatment options approved for the condition in more than a decade, leaving patients with limited choices.

According to Tonix CEO Seth Lederman, M.D., many patients with fibromyalgia are prescribed opioids within 18 months of diagnosis, despite the associated risks of addiction.

“The fibromyalgia community has been waiting for a new drug for over 15 years,” Dr. Lederman said. “TNX-102 SL has the potential to address this gap and provide patients with a safer, effective alternative.”

TNX-102 SL, a 5.6 mg cyclobenzaprine HCl sublingual tablet, is a Fast Track-designated drug.

This status, granted by the FDA in July 2024, highlights the treatment’s importance in addressing an unmet medical need.

Efficacy and safety data from Phase 3 trials

The NDA submission is backed by results from two pivotal Phase 3 clinical trials—RELIEF and RESILIENT—both of which demonstrated significant efficacy in reducing fibromyalgia-associated daily pain.

The RELIEF trial, completed in December 2020, met its primary endpoint, showing a statistically significant reduction in pain compared to placebo (p=0.010).

The confirmatory RESILIENT study, completed in December 2023, reinforced these findings with a stronger p-value of 0.00005.

Both trials evaluated TNX-102 SL as a bedtime treatment over a 14-week period.

The drug was generally well tolerated, with the most common side effect being temporary numbness of the tongue or mouth, which was mild and rarely led to treatment discontinuation.

Systemic adverse events, excluding COVID-19 cases, were observed in fewer than 4% of participants.

Tonix emphasized that the safety and efficacy data meet the criteria required for FDA approval, with no new safety concerns identified during the studies.