Flexion Therapeutics Enrolls First Patients in Phase 2 Trial of ZILRETTA® (triamcinolone acetonide extended-release injectable suspension) in OA of the Shoulder and Adhesive Capsulitis

Flexion Therapeutics, Inc. (Nasdaq:FLXN) today announced that the first three patients were enrolled in a clinical trial to evaluate the efficacy of ZILRETTA (triamcinolone acetonide extended-release injectable suspension) in patients with either shoulder osteoarthritis (OA) or adhesive capsulitis (AC), also known as frozen shoulder.

BURLINGTON, Mass., Dec. 17, 2019 (GLOBE NEWSWIRE) -- Flexion Therapeutics, Inc. (Nasdaq:FLXN) today announced that the first three patients were enrolled in a clinical trial to evaluate the efficacy of ZILRETTA (triamcinolone acetonide extended-release injectable suspension) in patients with either shoulder osteoarthritis (OA) or adhesive capsulitis (AC), also known as frozen shoulder. The Phase 2 double-blind, placebo-controlled, study is expected to enroll up to 250 patients – approximately 135 with shoulder OA and 115 with shoulder AC.

“Shoulder OA and AC are both associated with pain and limited range of motion which can significantly compromise a person’s function and quality of life,” said Michael Clayman, M.D., President and Chief Executive Officer of Flexion. “ZILRETTA may offer these patients an important non-surgical alternative that could provide substantial and durable pain relief.”

The Phase 2 trial, known as the RANGE study, will separate cohorts of patients by their diagnosis of shoulder OA or AC into two parallel groups. Patients in each cohort will be randomized (1:1) to either a single intra-articular injection of ZILRETTA or normal saline. The primary endpoint for both cohorts of the trial is the magnitude of pain relief versus placebo as measured by the overall change in daily shoulder pain with movement score from baseline to 8 weeks post injection. Patients in each cohort will be stratified by baseline pain scores. Shoulder AC patients will be further stratified by pain duration since onset and will also utilize a home exercise program during the study.

Each participant will be evaluated for 24 weeks following injection. The trial is expected to complete in the first half of 2021.

Indication and Select Important Safety Information for ZILRETTA® (triamcinolone acetonide extended-release injectable suspension)

Indication: ZILRETTA is indicated as an intra-articular injection for the management of osteoarthritis pain of the knee. It is not intended for repeat administration.

Contraindication: ZILRETTA is contraindicated in patients who are hypersensitive to triamcinolone acetonide, corticosteroids or any components of the product.

Warnings and Precautions:

  • Intra-articular Use Only: ZILRETTA has not been evaluated and should not be administered by epidural, intrathecal, intravenous, intraocular, intramuscular, intradermal, or subcutaneous routes. ZILRETTA should not be considered safe for epidural or intrathecal administration.
  • Serious Neurologic Adverse Reactions with Epidural and Intrathecal Administration: Serious neurologic events have been reported following epidural or intrathecal corticosteroid administration. Corticosteroids are not approved for this use.
  • Hypersensitivity reactions: Serious reactions have been reported with triamcinolone acetonide injection. Institute appropriate care if an anaphylactic reaction occurs.
  • Joint infection and damage: A marked increase in joint pain, joint swelling, restricted motion, fever and malaise may suggest septic arthritis. If this occurs, conduct appropriate evaluation and if confirmed, institute appropriate antimicrobial treatment.

Adverse Reactions: The most commonly reported adverse reactions (incidence ≥1%) in clinical studies included sinusitis, cough, and contusions.

Please see ZilrettaLabel.com for full Prescribing Information.

On October 6, 2017, ZILRETTA was approved by the U.S. FDA as the first and only extended-release intra-articular therapy for patients confronting osteoarthritis-related knee pain. ZILRETTA employs proprietary microsphere technology combining triamcinolone acetonide — a commonly administered, short-acting corticosteroid — with a poly lactic-co-glycolic acid (PLGA) matrix to provide extended pain relief. The pivotal Phase 3 trial on which the approval of ZILRETTA was based showed that ZILRETTA significantly reduced knee pain for 12 weeks, with some people experiencing pain relief through Week 16. Learn more at www.zilretta.com.

About Shoulder Osteoarthritis & Adhesive Capsulitis
Osteoarthritis (OA), also known as degenerative joint disease, affects more than 30 million adults living in the United States and accounts for more than $185 billion in annual expenditures. It is estimated that more than 30% of the population over the age of 60 have symptomatic shoulder OA.¹ Adhesive capsulitis (AC) is a long lasting, painful shoulder condition commonly known as “frozen shoulder,” with patients experiencing significant loss of range of motion. The average age of onset in patients is 55 years of age, with AC being more common in females and people with diabetes mellitus.²

About Flexion Therapeutics
Flexion Therapeutics (Nasdaq:FLXN) is a biopharmaceutical company focused on the development and commercialization of novel, local therapies for the treatment of people with musculoskeletal conditions, beginning with osteoarthritis, the most common form of arthritis. Flexion is building a portfolio of non-opioid therapeutics, with the goal of making a meaningful difference in the lives of patients. The Company’s core values are focus, ingenuity, tenacity, transparency and fun. Visit flexiontherapeutics.com.

Forward-Looking Statements
This release contains forward-looking statements that are based on the current expectations and beliefs of Flexion. Statements in this press release regarding matters that are not historical facts, including, but not limited to, statements relating to the future of Flexion; expected timing and scope of clinical trials; expected increases in the rate of individuals with OA of the knee; and the potential therapeutic and other benefits of ZILRETTA, 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 inherent in clinical development and the regulatory approval process, including the risk of delays in clinical trials and that future clinical results may not be consistent with prior results; risks related to the market and market conditions; and other risks and uncertainties described in our filings with the Securities and Exchange Commission (SEC), including under the heading “Risk Factors” in our Quarterly Report on Form 10-Q for the quarter ended September 30, 2019 filed with the SEC on November 7, 2019 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.


  1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3556427/
  2. https://www.ncbi.nlm.nih.gov/books/NBK532955/


Scott Young
Vice President, Corporate Communications & Investor Relations
Flexion Therapeutics, Inc.
T: 781-305-7194

Julie Downs
Senior Manager, Corporate Communications & Investor Relations
Flexion Therapeutics, Inc.
T: 781-305-7137

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