Intermittent treatment of knee osteoarthritis with oral chondroitin sulfate: a one-year, randomized, double-blind, multicenter study versus placebo.

Objective: To investigate the efficacy and tolerability of a 3-month duration, twice a-year, intermittent treatment with oral chondroitin sulfate (CS) in knee osteoarthritis (OA) patients.

Design: A total of 120 patients with symptomatic knee OA were randomized into two groups receiving either 800mg CS or placebo (PBO) per day for two periods of 3 months during 1 year. Primary efficacy outcome was Lequesne's algo-functional index (AFI); secondary outcome parameters included VAS, walking time, global judgment, and paracetamol consumption.