Hylan G-F 20 single-injection formulation

Hylan G-F 20, a cross-linked hyaluronic acid derivative, is an elastoviscous, high-molecular-weight (average 6000 kDa) fluid with rheological properties similar to those of knee synovial fluid of healthy young individuals. In a 26-week, randomized, double-blind, multicentre study in patients with symptomatic primary osteoarthritis of the knee (n = 253), one intra-articular injection of hylan G-F 20 (single-injection formulation) into the target knee significantly relieved pain (as measured by the Western Ontario and McMaster Universities Osteoarthritis Index pain [WOMAC A] subscale), including pain while walking on a flat surface (as assessed by the WOMAC A1 subscore), compared with placebo. Observer-reported disease status and patient-reported health status were also significantly improved in hylan G-F 20-treated patients compared with placebo-treated patients. A single intra-articular injection of hylan G-F 20 was generally well tolerated, with an adverse event profile similar to that of placebo. Repeat administration of hylan G-F 20 after 6 months had a similar tolerability profile to that of the initial injection. However, no patient who developed a target-knee adverse event after their first injection experienced such an event following their second injection.