Previous clinical studies investigating the efficacy of chondroitin in the management of knee osteoarthritis (OA) yielded inconclusive findings due to idiosyncratic study design or differences in the composition and purity of the chondroitin used. As a result, the European Medicines Agency (EMA) recommended that testing be done according to a standard study design of 6-months duration and a 3-arm study design including a placebo and an active comparator assessing 2 co-primary endpoints of pain and function. Results from this landmark, double blind, randomized trial found that chondroitin sulfate is as effective as celecoxib (a non-steroidal anti-inflammatory drug, or NSAID) and superior to placebo in reducing pain and improving function in patients with knee OA.
Researchers led by the Department of Public Health, Epidemiology and Health Economics at Liège State University (Liège, Belgium) recruited 604 patients (>50 y/o) with primary knee OA from Belgium, Czech Republic, Italy, Poland and Switzerland. Patients were randomly assigned to (1) pharmaceutical-grade chondroitin sulfate (≥ 95% purity of 4 & 6 isomers of chondroitin sulfate; 800 mg/day), celecoxib (200 mg/day), or (3) placebo for 6 months. Pain and function were assessed by the Visual Analog Scale (VAS) and the Lequesne Index (LI), respectively, at 1 month, 3 months and 6 months.
The researchers found that both the chondroitin sulfate and celecoxib resulted in a statistically greater reduction in VAS scores compared with the placebo after 6 months; the difference between chondroitin sulfate and celecoxib was not statistically different. Similarly, both chondroitin sulfate and celecoxib induced a significantly greater reduction in LI at 3 and 6 months compared with the placebo, with no difference between chondroitin sulfate and celecoxib. The study authors concluded that pharmaceutical-grade chondroitin sulfate should be considered as a first-line treatment in the management of knee OA.
The study results were published in the journal Annals of the Rheumatic Diseases (May 2017).
Why is this clinically important?
- OA is the most common form of arthritis and a major cause of pain, loss of function and disability
- The main medications for symptom suppression are acetaminophen and NSAIDs; however, the former is linked to liver toxicity and questionable efficacy whereas the latter is associated with gastrointestinal and cardiovascular side effects when used long-term
- Compounds with a preferable efficacy and safety profile such as chondroitin would be a valuable alternative for these patients
- Clinicians should consider implementing high-quality chondroitin sulfate (from reputable nutraceutical or pharmaceutical companies) as first-line therapy in management of OA
[1.] Reginster, J.Y., et al., Pharmaceutical-grade Chondroitin sulfate is as effective as celecoxib and superior to placebo in symptomatic knee osteoarthritis: the ChONdroitin versus CElecoxib versus Placebo Trial (CONCEPT). Ann Rheum Dis, 2017.