Slow-acting, disease-modifying osteoarthritis agents

This article describes agents used in the treatment of osteoarthritis (OA) that potentially modify the articular cartilage, synovial fluid, and synovium of the affected joint. The composition, pharmacokinetics,mechanism of action, in vitro and in vivo evidence of efficacy, and safety aspects of slow-acting, disease-modifying OA agents are described. Included are descriptions of the use of the orally administered nutritional supplements Cosequin and Glycoflex and the parenterally administered products polysulfated glycosaminoglycan (PSGAG), pentosan polysulfate (Cartrophen), and hyaluronan. Information on the use of tetracyclines also is presented.