Objectives: To evaluate the efficacy and tolerability of chondroitin sulfate (CS) in knee osteoarthritis.
Patients and methods: A 24-week, randomized placebo controlled trial of CS (1 g/day) was performed on patients with symptomatic knee osteoarthritis. Pain on daily activities and Lequesne’s index were the primary efficacy criteria. Secondary outcomes include the rate of responders according to the OMERACT-OARSI criteria, quality of life, patient's/physician's global assessments and carry-over effect after treatment. Biochemical markers of bone (CTX-I), cartilage (CTX-II) and synovium (hyaluronic acid) metabolism were also measured. Safety was assessed by recording adverse events (AEs). Statistical analysis was performed on the inter-group differences in the intention-to-treat population.
Results: 307 patients were included. Twenty-eight (9%) discontinued the study for lack of efficacy or AEs. At the end of treatment, decrease of pain was -26.2±24.9 mm and -19.9±23.5 mm and improved function was -2.4±3.4 (-25%) and -1.7±3.3 (-17%) in the CS and placebo groups, respectively (P=0.029 and 0.109). The OMERACT-OARSI responder rate was 68% in the CS and 56% in the placebo group (P=0.03). Investigator's assessments and SF-12 physical component reported improvement more frequently in the CS than in the placebo group (P=0.044 and 0.021 respectively). No significant difference was observed between treatment groups for changes in biomarkers over 24 weeks. However, there was a significant difference between non-responders and responders according to the OARSI criteria for 24 week changes of CTX-I (P=0.018) and CTX-II (P=0.014). Tolerance was considered as satisfactory.
Conclusion: This study failed to demonstrate an efficacy of CS on the two primary criteria considered together, although CS was slightly more effective than placebo on pain, OMERACT-OARSI response rate, investigator's assessment and quality of life.
- OMERACT-OARSI responders
- biological markers
- chondroitin sulfate
- knee osteoarthritis
- randomised controlled trial