The US Food and Drug Administration (FDA) has accepted for review the New Drug Application (NDA) for Zilretta (FX006; Flexion Therapeutics, Burlington, MA) for the treatment of patients with knee osteoarthritis (OA).

The NDA submission was based on data from a randomized, double blind, placebo and active-comparator (immediate-release triamcinolone acetonide) controlled Phase 3 trial in 484 patients with OA of the knee. 

Results showed that Zilretta demonstrated a highly significant (P<0.0001) reduction in average daily pain vs. placebo at week 12 (primary endpoint), with durable and clinically meaningful pain relief in patients with moderate to severe OA knee pain. Additionally, Zilretta was found to have a tolerable safety profile, with no serious drug-related adverse events reported.

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Zilretta is an intra-articular, extended-release formulation of triamcinolone acetonide in a poly lactic-co-glycolic acid (PLGA) co-polymer matrix. It is formulated using Flexion’s proprietary microsphere technology to enhance and prolong the clinical effect of intra-articular corticosteroid treatment for OA knee pain.

The FDA has established a Prescription Drug User Fee Act (PDUFA) target action date of October 6, 2017 to make a decision on the NDA.

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Flexion Therapeutics announces new drug application for Zilretta™ (FX006) accepted by U.S. Food and Drug Administration [news release]. Burlington, MA. Flexion Therapetics. Accessed February 8, 2017.

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This article originally appeared on MPR