the effect of hydroxychloroquine on symptoms of knee osteoarthritis: a double-blind randomized controlled clinical trial

background: osteoarthritis is a degenerative joint disorder of articular cartilage and is the most common type of arthritis in the elderly. there are only a few reports regarding the use of hydroxychloroquine in the treatment of osteoarthritis. methods: to investigate the effects of hydroxychloroquine on the symptoms of mild to moderate knee osteoarthritis (kellgren and lawrence grade ii and iii), we performed a double-blind, placebo-controlled study in 44 patients. the patients were randomly assigned to two groups: one group received hydroxychloroquine pills (200 mg twice daily) and the other group received placebo pills. symptoms were assessed by the western ontario and mcmaster universities osteoarthritis index (womac) at baseline and at the end of weeks 4, 8, 12, 16, 20, and 24. results: approximately, 98% of the patients were women at an average age of 47 years. there was no significant difference in the baseline characteristics between the two groups. in the placebo group, maximum improvement occurred at the 4th week; and during the remaining time, there was no significant improvement. in the hydroxychloroquine group, maximum improvement occurred at the 8th week and persisted over the entire remaining follow-up period. there were significant differences between the two groups regarding the degree of reduction in the womac total score and the womac subscales scores of pain, stiffness, and function at the end of weeks 4, 8, 12, 16, 20, and 24. conclusion: hydroxychloroquine conferred significant improvement in the symptoms of mild to moderate knee osteoarthritis in our patients and may, accordingly, be recommended for knee osteoarthritis treatment. trial registration number: irct138709121479n1