Objective: To assess the efficacy and safety of chondroitin sulfate (CS) 1 g/day per os compared to placebo, in a double blind, randomized, parallel group study, with 3 months treatment followed by a 3 month posttreatment period, in patients with femorotibial osteoarthritis (OA).
Methods: The main criterion was the functional handicap assessed by Lequesne's algofunctional index (AFI). Secondary efficacy criteria were: self-assessed pain with activity and at rest, self-assessed impact of OA on daily living, patient and physician assessed overall change in patient state since the previous visit, and daily NSAID and analgesic consumption, all evaluated monthly. The main analysis was performed on the intent-to-treat (ITT) population at treatment endpoint compared to baseline (Day 0).
Results: The ITT efficacy data set comprised 130 patients (63 in CS group and 67 in placebo group). At treatment endpoint, the AFI showed greater but nonsignificant improvement in the CS than in the placebo group. Improvement became significant (p = 0.02) in the completer population (n = 114). In the ITT population, all variables tended towards greater improvement in the CS than the placebo group. In the completer population, pain at rest also significantly decreased in the CS group compared to the placebo group (p = 0.03), and, one month after treatment, CS had a significantly higher persistent effect than placebo on the AFI (p = 0.01), pain with activity (p = 0.001), physician assessed patient state (p = 0.05), and most other efficacy criteria. Adverse event rates did not differ significantly.
Conclusion: We observed a trend towards efficacy of CS 1 g/day compared to placebo with good tolerability after 3 month treatment, and persistent efficacy one month posttreatment. Further investigations are required to confirm this trend.