Flexion Shares Lower by 4.5% After Initiating Phase 2b Confirmatory Dose-Ranging Trail With FX006

Flexion Therapeutics, Inc.

announced today that the first patient has been dosed in a confirmatory Phase 2b clinical trial designed to further evaluate the safety, tolerability and efficacy of certain doses of FX006 as a treatment for relieving pain associated with OA of the knee. FX006 is Flexion's novel, non-opioid, sustained-release, intra-articular (IA) formulation of triamcinolone acetonide (TCA). It is designed to provide prolonged pain relief for the treatment of mild to moderate OA of the knee, while avoiding untoward systemic effects associated with immediate release steroids. Michael Clayman, M.D., Flexion Therapeutics President and CEO, said, "We believe that the superior performance of FX006 in a completed Phase 2b trial against active comparator –reported at the 2013 American College of Rheumatology Annual Scientific Meeting – illustrates the potential of this product candidate to make a meaningful difference for the many patients who suffer the often debilitating pain of osteoarthritis of the knee." Dr. Clayman continued, "Our newly initiated Phase 2b confirmatory trial is powered to provide pivotal data for FX006 compared to placebo. We anticipate receiving topline data from this trial in the first half of 2015 and, if positive, these data would set the stage for Phase 3 development next year." In the newly initiated Phase 2b confirmatory study, approximately 300 patients will be randomized and treated with a single injection of either 20 mg or 40 mg of FX006 or placebo and will be evaluated for 20 weeks. The primary outcome measure is the weekly mean of the average daily pain intensity scores as assessed using an 11-point numerical rating scale. Secondary endpoints include Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC®), patient global impression of change, clinical global impression of change and responder status. Flexion Therapeutics is concurrently conducting a study of FX006 synovial fluid pharmacokinetics in patients with OA to better characterize local exposure and assist in setting the interval for repeat dosing. Topline data from that trial are expected in the second quarter of 2014.