Cochrane review confirms viscosupplement efficacy on knee OA

Meta-analysis shows hyaluronic acid injections have significant effect on knee arthritis symptoms compared to placebo.

Viscosupplementation using hyaluronic acid-based drugs provides superior relief of osteoarthritic knee pain compared to placebo injections, according to the results of a systematic meta-analysis by the Cochrane Collaboration, an independent international organization.

In the study, the organization reviewed published clinical trials conducted in the United States, Europe and Canada to determine the weighted mean difference (WMD) in efficacy between hyaluronic acid-based viscosupplementation and placebo. The study included 37 trials comparing such drugs to placebo, nine trials that included comparisons with intra-articular corticosteroids and five trials that included comparisons with nonsteroidal anti-inflammatory drugs. All patients included in the trials had radiologically confirmed knee osteoarthritis (OA), according to the study.

The authors of the study concluded that viscosupplementation effectively reduces knee pain and improved function caused by OA, particularly five to 13 weeks after injection.

Additionally, the study found that several viscosupplement products, including Synvisc (hylan G-F 20, Genzyme Corp.), had greater efficacy than steroid injections, according to a press release from Genzyme Corp.

The Cochrane review included 18 randomized, controlled trials comparing Synvisc to placebo. The review found that Synvisc had a significantly better WMD than placebo on weight-bearing pain at 13 to 26 weeks after treatment (P=.006). The drug also provided significantly better functional improvement at five to 13 weeks after treatment (P<.00001), according to the Genzyme press release.

“The Cochrane review has shown that hyaluronic acid has a significant effect on controlling knee arthritis symptoms when compared to placebo, and that Synvisc and other hyaluronic acid products have a clinically proven, solid position as a treatment option for pain associated with knee osteoarthritis,” Vijay Vad, MD, assistant professor of rehabilitation at the Hospital for Special Surgery, New York City, said in the release.

Synvisc is currently approved in more than 60 countries worldwide for treating OA knee pain. It is also approved in the European Union and Canada for treating OA hip pain, according to the release.

For more information:
Bellamy N, Campbell J, Robinson V, et. al. Viscosupplementation for the treatment of osteoarthritis of the knee. Cochrane Database Syst Rev. 2005. Issue 2; No.:CD005321.