« Back

"No rationale" seen for continued use of hylan in knee osteoarthritis

Wednesday, December 05 2007 | Comments

---

What's This? NEW YORK (Reuters Health) - For osteoarthritis of the knee, intra-articular injections of hylan or hyaluronic acids are equally effective, although hylan has the potential to cause more local adverse events, a study shows. This coupled with the higher cost of hylan prompted researchers to conclude, "We see no rationale for the continued use of hylan in patients with knee OA."

Treatment with hylan or hyaluronic acids is thought to restore synovial fluid viscoelasticity, which is depleted in patients with OA, note Dr. Peter Juni from University Berne, Switzerland and colleagues. Hyaluronic acids were modified to form high molecular weight hylans, to increase viscosity and decrease clearance from the joint.

In the current study, reported in the November issue of Arthritis and Rheumatism, Dr. Juni's team compared the efficacy and safety of hylan and two hyaluronic acids in 660 patients with symptomatic knee OA.

Patients were randomly assigned to receive one cycle of three intra-articular injections per knee of one of the three preparations: a high molecular weight cross-linked hylan; a non-cross-linked medium molecular weight hyaluronic acid of avian origin, or a non-cross-linked low molecular weight hyaluronic acid of bacterial origin.

Pain scores were measured after 6 months, after which patients were offered a second cycle of treatment.

There was no evidence for clinically relevant differences in efficacy between any of the three evaluated preparations in any of the analyses performed. "Pain relief was similar in all 3 groups," the investigators report.

"However, the most expensive, cross-linked, high molecular weight hylan was associated with a trend toward more local adverse events, particularly during the second cycle," they note.

To their knowledge, Dr. Juni and colleagues say, this study is the largest viscosupplementation trial to date, and the only industry-independent trial.

"Given the consistent and robust lack of an advantage in efficacy of hylan over hyaluronic acids and the potential for an increased risk of local adverse events," the researchers conclude, "we see no indication for further clinical trials with this preparation."

Arthritis Rheum 2007;56:3610-3619.

Print  |  E-mail