Single intra-articular injection of lightly cross-linked hyaluronic acid reduces knee pain in symptomatic knee osteoarthritis: a multicenter, double-blind, randomized, placebo-controlled trial

Purpose The primary objective was to demonstrate the safety and effectiveness of Monovisc (TM) in the relief of joint pain in patients with idiopathic knee OA compared to saline injection. It was hypothesized that patient success, defined as >= 50% improvement from baseline and = 20 mm absolute improvement from baseline in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) visual analog scale (VAS) pain score, would be greater in the Monovisc (TM) group compared to the Saline control group. Methods In this multicenter, double-blind, randomized, placebo-controlled trial, patients with idiopathic, symptomatic, knee OA were randomized to either 4 ml single injection of Monovisc (TM) or 4 ml injection of 0.9% saline. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was used to assess patient outcomes at 2, 4, 8, 12, 20, and 26 weeks post-injection. The primary effectiveness endpoint was a 50% improvement and >= 20 mm improvement from baseline in the WOMAC pain through 26 weeks. Secondary outcome measures included a >= 20 mm improvement from baseline on the WOMAC physical function, patient global assessment, evaluator global assessment, and knee range of motion. Results 369 patients (154 male, 215 female) were randomized to either Monovisc (TM) or saline. The Monovisc (TM) group had a significantly greater rate of patient success (e.g. >= 50% improvement and >= 20 mm absolute improvement from baseline in the WOMAC pain through Week 26) compared to saline (p = 0.043). Conclusions Monovisc (TM), a single-injection intra-articular HA device, is a safe and effective treatment for providing a clinically meaningful reduction in knee pain within 2 weeks. The results of this study support the use of a single injection of hyaluronic acid (Monovisc (TM)) for patients with symptomatic knee OA in patients older than 45 years, as a safe and effective alternative for patients who may want an alternative treatment modality or may not be candidates for partial or total knee replacement.