Access to Highly Purified Chondroitin Sulfate for Appropriate Treatment of Osteoarthritis: A Review

Current pharmacological therapies for osteoarthritis are symptom-focused and aimed at controlling pain. However, currently approved symptom-modifying agents do not restore the structure and function of damaged joints. Symptomatic slow-acting drugs in osteoarthritis (SySADOAs), including the sulfated glycosaminoglycan, chondroitin sulfate, have shown promising beneficial effects on the pain and other symptoms of osteoarthritis, and some may also have a positive effect on cartilage, slowing the progression of joint deterioration in osteoarthritis. A highly-purified, standardized, pharmaceutical-grade preparation of chondroitin sulfate has shown activity in osteoarthritis and has become one of the most prescribed SySADOAs. However, in many countries, formulations of chondroitin sulfate of various sources and purity are available as food supplements or nutraceuticals. As the effects of chondroitin sulfate could vary according to the characteristics of the chondroitin sulfate employed, including source, purity, or structural organization, clinical data from well-designed studies of pharmaceutical-grade chondroitin sulfate should not be extrapolated to support clinical efficacy claims of food supplements; nor should results from trials of chondroitin sulfate-containing food supplements be used to draw conclusions about the efficacy of pharmaceutical-grade chondroitin sulfate. This article reviews the evidence for the role of highly-purified pharmaceutical-grade chondroitin sulfate in the treatment of osteoarthritis and examines the efficacy and safety concerns of other formulations of chondroitin sulfate. Highly-purified pharmaceutical-grade chondroitin sulfate has mild-to-moderate efficacy in the treatment of symptomatic osteoarthritis, with clinically meaningful efficacy.