2nd Phase 3 Study of Low-dose Oral Treatment for Fibromyalgia Gets Underway

2nd Phase 3 Study of Low-dose Oral Treatment for Fibromyalgia Gets Underway

Tonix Pharmaceuticals announced that the first patient has been dosed in RE-AFFIRM, the company’s second Phase 3 clinical trial evaluating its cyclobenzaprine HCl sublingual tablets, known as TNX-102 SL, as a low-dose nighttime treatment for fibromyalgia.

TNX-102 SL is a proprietary sublingual (under the tongue) eutectic formulation of cyclobenzaprine (CBP), engineered to deliver a low dose of CBP to the bloodstream through mucosal membrane absorption. CBP works as an antagonist at the serotonin-2A, alpha-1 adrenergic, and histamine H1 receptors. Due to its transmucosal absorption, the proprietary drug candidate avoids first-pass metabolism and decreases exposure to the active metabolite norcyclobenzaprine, an undesirable molecule due to its long plasma half-life. 

“We have taken an important step forward in advancing the clinical development of a much-needed new therapy for the 5 to 15 million people in the U.S. suffering with fibromyalgia by initiating our second pivotal Phase 3 study of TNX-102 SL in fibromyalgia. This is a once-daily bedtime sublingual formulation designed to treat fibromyalgia by improving sleep quality,” Seth Lederman, M.D., president and chief executive officer of Tonix, said in a press release. “given the results of our Phase 2b BESTFIT study, we believe TNX-201 SL could offer therapeutic benefits to patients with fibromyalgia across a broad spectrum of symptoms.”

The clinical phase of AFFIRM, the company’s first Phase 3 study of TNX-102 SL in fibromyalgia, is complete and data is expected to be announced soon.

RE-AFFIRM (NCT02829814) is a 12-week, randomized and double-blind, placebo-controlled trial to assess the safety and efficacy of TNX-102 SL tablets, 2.8 mg, taken daily at bedtime as a treatment for fibromyalgia. The study, which is taking place at 32 sites across the United States, is currently recruiting adults, ages 18 to 75, with a diagnosis of primary fibromyalgia established by 2010 ACR criteria. More information, including enrollment information, is available on the study’s clinical trials.gov website.

The primary efficacy endpoint is the proportion of patients with at least  a 30 percent or greater improvement, from baseline to week 12, in the weekly average of daily self-reported pain severity, scored using an 11-point (0-10) numeric response scale. Results from a previous Phase 2b study provided strong evidence that TNX-102 SL 2.8 mg taken nightly had beneficial effects on pain, sleep and other FM symptoms.

RE-AFFIRM and AFFIRM are largely identical trials, both taking place in the U.S., assessing  TNX-102 SL in about 500 fibromyalgia patients (AFFIRM is no longer recruiting). The U.S. Food and Drug Administration (FDA) requires two well-documented registration-quality clinical trials for marketing approval of a new medicine.