Glucosamine for osteoarthritis: part I, review of the clinical evidence.

Glucosamine is a popular nutritional supplement for OA. This supplement has shown moderate efficacy in meta-analysis and large industry-sponsored clinical trials. However, smaller independent studies have not shown significant benefit. It is difficult to compare these clinical trials due to heterogeneity in trial design, differences in glucosamine products, and differences in osteoarthritic populations being studied. The National Center for Complementary and Alternative Medicine and the National Institute of Arthritis and Musculoskeletal and Skin Disease (NIAMS/NCCAM) have funded a multicenter five arm placebo controlled study called The Glucosamine Arthritis Intervention Trial (GAIT). GAIT spans 24 weeks, enrolling 1588 subjects, at 13 centers comparing the efficacy of glucosamine sulfate, chondroitin sulfate, glucosamine with chondroitin, to placebo and compared to celecoxib for knee OA. This study may have final data in March 2005.