Study Shows No Benefit with Hyaluronic Acid

Reporting in the Annals of Rheumatic Diseases (December2004), French researchers discovered that injections of the newhyaluronic acid compound called NRD101 have the same resultfor osteoarthritis (OA) of the knee as placebo injections.Hyaluronic acid is believed to restore elasticity to the synovialfluid that surrounds the knee joint, which is depleted in patientswith OA of the knee. Yet, the effectiveness of this approach isunproven. Therefore, the researchers compared the safety andeffectiveness of NRD101 with an orally administered drug, diacerein,in 300 patients. Previous research had shown that diacereinhad a structural benefit in hip OA.

For the study, the participants were assigned to receive 3courses of NRD101 injections, each involving 1 injection weeklyfor 3 weeks, every 3 months, along with a placebo capsule;placebo injections and diacerein twice daily; or placebo injectionsand capsules. During the 1-year study, the patients and cliniciansevaluated symptoms, and x-rays were done to assessthe effects of treatment on the knee structure at the beginningand end of the study.

The results of the study showed that the patients in all 3groups had improvements of their symptoms. A small degree ofstructural weakening, however, occurred in each group. Theresearchers concluded that more research is needed to examineother treatment approaches using this route of administration.