Can Diacerein Act as a Disease-Modifier for Osteoarthritis?

Researchers have studied Diacerein to see if the medication can slow the progression of osteoarthritis. Disease-modifying drugs are known treatment options for rheumatoid arthritis and other inflammatory types of arthritis. But drugs that may modify the progression of osteoarthritis, slowing joint damage and decreasing the chance of disability, remain unproven. Unfortunately, Diacerein has yet to show that the risks outweigh its benefits, and typical osteoarthritis treatments haven't slowed the disease from advancing.

The Usual Treatments Don't Slow Disease Progression

Traditional non-drug treatments for knee osteoarthritis and hip osteoarthritis, two of the joints most affected by osteoarthritis, include weight loss, exercise, and avoidance of weight-bearing activities that increase stress to the joints.

The drugs and supplements physicians use to treat osteoarthritis include adequate vitamin D intake; analgesics such as Tylenol; NSAIDs (nonsteroidal anti-inflammatory drugs) such as naproxen and ibuprofen; supplements such as glucosamine sulfate; and joint injections. Alternative therapies are also among the popular treatment options. Other than weight loss, there has been no conclusive evidence that these treatment regimens slow down or prevent osteoarthritis.

Studies of Diacerein as an Osteoarthritis Disease-Modifier 

Studies have explored the potential of using diacerein to treat osteoarthritis of the knees and hips. Diacerein is an anti-inflammatory medication that works differently from the typical NSAIDS. Diacerein blocks interleukin-1, as opposed to inhibiting the cyclooxygenase (COX) pathway as NSAIDs do.

In studies, patients typically received prescriptions of 50 mg of diacerein twice per day. In 2006, the Cochrane Collaboration published a review of seven clinical studies involving diacerein that included 2,069 patients. It concluded that diacerein had a small effect on improving pain and slowing the progression of osteoarthritis compared to standard treatment with NSAIDs or placebo. The most common side effect associated with diacerein was diarrhea.

The Cochrane Collaboration updated their systematic review in 2013, adding three new trials of 141 participants. The new research confirmed that the strength of evidence for diacerein's effectiveness outcomes was low to moderate, and pain reduction was minimal. In osteoarthritis of the hip, there was a small benefit for reducing joint space narrowing, but it was probably not clinically relevant. There is a 24 percent risk of developing diarrhea as a result of diacerein use.

European Medicines Agency Imposes Restrictions 

On March 19, 2014, the Co-ordination Group for Mutual Recognition and Decentralised Procedures - Human (CMDh) endorsed restricting diacerein in the European Union. The decision became legally binding on Sept. 4, 2014. The group based its decision on the risk of patients developing severe diarrhea and liver problems because of the drug. In short, the group decided that diacerein's risks outweighed its benefits.

Is More Research on Diacerein Needed?

Rheumatologist Dr. Scott J. Zashin discussed diacerein as a possible treatment for osteoarthritis. "At this time, there is no definitive evidence that diacerein produces significant results as a disease-modifying drug for osteoarthritis," he told VeryWell. "Further study is needed to establish the short and long-term safety and effectiveness of diacerein for osteoarthritis."

The drug is not available in the United States, the European Union, Canada, Britain, or Australia. It may be available in select countries, subject to further regulation. The 2014 decision of the European Union to restrict the drug indicates that the possible side effects of the drug are more troublesome than any of its potential advantages.