486 patients with Kellgren-Lawrence grade II-III knee osteoarthritis were randomized to one of three groups: single intraarticular injection of 32mg extended-release triamcinolone (FX006; Flexion Therapeutics); single intraarticular injection of 40mg triamcinolone acetonide crystalline suspension (TAcs); or single intraarticular injection of placebo saline. Patients were assessed primarily with respect to change pain scores and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Follow-up was performed at 12 weeks and 24 weeks after injection. Results at 12 weeks demonstrated significantly greater reduction from baseline in average daily pain in the FX006 group compared to the placebo group, and significantly greater reduction in WOMAC scales in the FX006 group compared to both the placebo group and TAcs group. By 24 weeks, there were no significant between-group differences in efficacy measures.