Daily Oral Chondroitin Sulfate Oligosaccharides for Knee Joint Pain in Healthy Subjects: A Randomized, Blinded, Placebo-Controlled Study

The increased rate of population aging in Japan has led to an increase in the incidence of osteoarthritis (OA). Chondroitin sulfate has been reported to reduce the pain and swelling associated with OA and to improve knee function. We evaluated the safety and effects of oral chondroitin sulfate oligosaccharides on knee function in a randomized, double-blinded, placebo-controlled parallel group comparison study of healthy Japanese subjects with knee joint pain. Subjects were randomly divided into test and placebo groups and given either active-test capsules containing 100 mg of chondroitin sulfate oligosaccharides or placebo capsules daily for 8 weeks. The Japanese Knee Osteoarthritis Measure (JKOM), Visual Analog Scale (VAS), blood and physical examinations, and medical interviews were performed at weeks 0, 4, and 8, and the locomotive syndrome risk test was performed at weeks 0 and 8 during the test intake period. The JKOM scores did not significantly differ between the test groups. However, among subjects with worse VAS scores, those in the active test group had significantly lower JKOM scores at 8 weeks, compared to those in the placebo group. Moreover, chondroitin sulfate oligosaccharide treatment tended to improve the subjects' scores on the stand-up test, which evaluates the risk of locomotive syndrome. Furthermore, no abnormal changes or severe adverse events were observed during physical or blood examinations or medical interviews. Our results suggest that chondroitin sulfate oligosaccharides improve knee pain and are safe for 8-week intake.