Flexion Therapeutics Enrolls First Patient in Pharmacokinetic Study of Zilretta™ for Osteoarthritis of the Knee

BURLINGTON, Mass., Dec. 01, 2015 (GLOBE NEWSWIRE) -- Flexion Therapeutics, Inc. (Nasdaq:FLXN) announced today that it has enrolled its first patient in a pharmacokinetic (PK) study of Zilretta (also known as FX006). In this open-label, single administration clinical trial, researchers at four U.S. sites will study 40 mg of Zilretta administered as a single 5 mL intra-articular (IA) injection in 50 patients with osteoarthritis (OA) of the knee. The objective of the study is to provide additional characterization of the local concentrations of triamcinolone acetonide (TCA, or the active ingredient in Zilretta) in the knee over 20 weeks following a single injection.

OA is a painful and debilitating musculoskeletal disease that is characterized by IA inflammation, deterioration of articular cartilage, and degenerative changes to joint architecture. The incidence of OA is increasing rapidly, and the condition is expected to affect 45 million Americans by 2030. Current treatment options – including opioids and common anti-inflammatory medicines – are not always effective, and many carry serious risks and side effects.

“This study is being conducted in support of our planned New Drug Application (NDA) submission to the FDA, and is designed to determine the concentration of drug in the synovial fluid and plasma of patients with OA at multiple time points,” said Michael Clayman, M.D., Flexion Therapeutics President and Chief Executive Officer. “We anticipate making the NDA submission during the second half of 2016, and we continue to look forward to positioning Zilretta as a potential first-in-class IA treatment for patients with moderate to severe OA, providing them with a non-opioid, sustained-release pain therapy.”

Zilretta is intended to provide an extended-release of the TCA formulation over a three-month period into the patient’s synovial and peri-synovial tissues. Due to the large unmet need among OA patients, the FDA recently granted Zilretta with Fast Track designation.

About Zilretta
Zilretta is being developed as a potential first-in-class, IA, sustained-release, non-opioid treatment for patients with moderate to severe OA. Zilretta is designed to provide persistent concentrations of drug locally that both amplify the magnitude and prolong the duration of pain relief relative to standard corticosteroid injections. Zilretta uses a proprietary microsphere technology which addresses the limitations of current IA therapies by providing long-lasting, local analgesia while avoiding systemic side effects. To date, approximately 600 patients have been treated with Zilretta in clinical trials. In a completed Phase 2b dose-ranging clinical trial, Zilretta has demonstrated clinically meaningful and significantly improved pain relief compared to the current injectable standard of care, triamcinolone acetonide suspension. Zilretta has also been studied in a pivotal Phase 2b clinical trial against placebo and Flexion is currently conducting a Phase 3 clinical trial. These studies are designed to provide the required efficacy and safety data for the NDA submission of Zilretta.

About Flexion Therapeutics
Flexion is a clinical-stage specialty pharmaceutical company focused on the development and commercialization of novel pain therapies. The company is currently advancing a portfolio of local, injectable, non-opioid drug candidates that have the potential to provide better and more persistent analgesia compared with existing therapy. The company's lead product candidate, Zilretta, has been designed to provide improved analgesic therapy for the five million patients who receive IA injections for OA of the knee annually. The company also has two additional product candidates, FX007, a locally administered TrkA receptor antagonist for post-operative pain, and FX005, an IA, sustained-release p38 MAP kinase inhibitor for end-stage OA patients.

Forward-Looking Statements
Statements in this press release regarding matters that are not historical facts, including, but not limited to, statements relating to the future of Flexion; our ongoing development of Zilretta and our other product candidates; our plans for, and the expected timing of, our Zilretta NDA submission; our plans to commercialize Zilretta and its market potential; and the potential therapeutic and other benefits of Zilretta and our other product candidates, are forward-looking statements. These forward-looking statements are based on management's expectations and assumptions as of the date of this press release and are subject to numerous risks and uncertainties, which could cause actual results to differ materially from those expressed or implied by such statements. These risks and uncertainties include, without limitation, risks associated with the process of discovering, developing and obtaining regulatory approval for drugs that are safe and effective for use as human therapeutics; the fact that results of past clinical trials may not be predictive of subsequent trials; our reliance on third parties to manufacture and conduct clinical trials of Zilretta and our other product candidates, which could delay or limit their future development or regulatory approval; our ability to meet anticipated clinical trial completion dates and regulatory filing dates for Zilretta; the fact that we will require additional capital, including prior to commercializing Zilretta or any of our other product candidates, and may be unable to obtain such additional capital in sufficient amounts or on terms acceptable to us; the risk that our patents may be challenged or invalidated; competition from alternative therapies; regulatory developments and safety issues, including difficulties or delays in obtaining regulatory approvals to market Zilretta or our other product candidates; risks related to key employees, markets, economic conditions, health care reform, prices and reimbursement rates; and other risks and uncertainties described in our filings with the Securities and Exchange Commission (SEC), including under the heading "Risk Factors" in our most recent Annual Report on Form 10-K and subsequent filings with the SEC. The forward-looking statements in this press release speak only as of the date of this press release, and we undertake no obligation to update or revise any of the statements. We caution investors not to place considerable reliance on the forward-looking statements contained in this press release.

Investor Relations Contact David Carey Lazar Partners LTD T: 212-867-1768 dcarey@lazarpartners.com Media Relations Contact Mariann Caprino TogoRun 917.242.1087 M.Caprino@togorun.com Corporate Contact Fred Driscoll Chief Financial Officer Flexion Therapeutics, Inc. T: 781-305-7763 fdriscoll@flexiontherapeutics.com

Source:Flexion Therapeutics