Major Trial Finds Diacerein Does Not Relieve Knee Osteoarthritis Pain

Diacerein, a plant-derived anti-inflammatory drug used to treat osteoarthritis in parts of Europe and Asia, did not relieve pain or improve function in people with knee osteoarthritis, according to a major trial led by the University of Tasmania's Menzies Institute for Medical Research. The drug failed even among patients with inflammation inside the joint, known as effusion synovitis, who were considered especially likely to benefit.

The trial, called DICKENS, was led by Associate Professor Dawn Aitken, head of the Musculoskeletal Research Group at Menzies, and is the largest global study to examine whether diacerein can reduce pain in people with knee osteoarthritis who also have effusion synovitis. Diacerein comes from plants including rhubarb and aloe vera and works differently from conventional pain relievers by targeting inflammatory pathways involved in joint disease.

"We designed this large trial to test diacerein in a group of osteoarthritis patients who we thought would have the best chance at benefiting from the drug and found that it did not improve pain or function or decrease local knee inflammation," Aitken said. "We were hoping that if the drug was effective, it could be included on the Australian Register of Therapeutic Goods as an approved treatment for osteoarthritis in Australia. Unfortunately, it's back to the drawing board to find more effective drug therapies."

Osteoarthritis is the most common type of arthritis, affecting one in five Australians older than 45 and driving much of the pain, disability and joint replacement surgery linked to the disease, yet few effective medication options exist. The trial was published in JAMA Internal Medicine, which Aitken said underscores the importance and rigor of the research.

Aitken said the most effective therapies currently available for osteoarthritis are education, exercise, weight management and psychological support, and that anyone taking diacerein should speak with their doctor before stopping the medication.