Chondroitin Sulfate Equals Celecoxib for Knee Osteoarthritis

Chondroitin sulfate at 800 mg/d is superior to placebo and similar to celecoxib for patients who have symptomatic knee osteoarthritis, a new study found.

Researchers examined the efficacy of pharmaceutical-grade chondroitin sulfate for managing symptomatic knee osteoarthritis using the European Medicines Agency’s recommendations for assessing novel agents.

Led by Jean-Yves Reginster, MD, PhD of Liege State University in Belgium, the investigators compared the impact of chondroitin sulfate on pain and functioning with that of celecoxib and placebo.

Osteoarthritis can occur in any joint, but osteoarthritis of the knees and hips has a particularly large impact because they are weight-bearing joints, the authors noted.

Although there have been differences in evidence-based guidelines on how best to treat patients with knee osteoarthritis, symptomatic slow-acting drugs for osteoarthritis such as chondroitin sulfate have grown in favor because of their safety and tolerability. For example, chondroitin sulfate alone and in combination with crystalline glucosamine sulfate has been shown to reduce pain in persons with osteoarthritis.

In 2010, the European Medicines Agency produced a “Guideline on Clinical Investigation of Medicinal Products Used in the Treatment of Osteoarthritis” that recommended testing of the efficacy of chemical entities used in the treatment of symptomatic osteoarthritis using the following parameters: (1) a minimum 6-month study duration; (2) a 3-arm study design, including a placebo and an active comparator; and (3) 2 co-primary endpoints evaluating pain and function.

This, the first-known study of chondroitin sulfate for the management of knee osteoarthritis conducted in total accordance with the European Medicines Agency recommendations, was published online May 22 in Annals of the Rheumatic Diseases.

The study

This study was a prospective, randomized, double blind, placebo- and celecoxib-controlled trial with 604 outpatients age 50 years and older who had a diagnosis of primary knee osteoarthritis based on American College of Rheumatology criteria. Patients were enrolled between June 2014 and October 2015 and represented Belgium, the Czech Republic, Italy, Poland, and Switzerland.

Patients were randomly assigned to 1 of 3 groups: (1) chondroitin sulfate: 1 tablet of chondroitin sulfate 800 mg and 1 capsule of placebo celecoxib; (2) celecoxib: 1 tablet of placebo chondroitin sulfate and 1 capsule of celecoxib 200 mg (Celebrex Pfizer); and (3) placebo: 1 tablet of placebo chondroitin sulfate and 1 capsule of placebo celecoxib. All treatments were taken daily, in the evening, for a total of 182 days (~6 months). No other interventions for osteoarthritis were allowed during the study.

The primary endpoints were 2-fold: (1) pain reported by the patient and assessed on a 100 mm Visual Analogue Scale and (2) the Lequesne Index, which integrates function and pain to generate a score ranging from 0 to 24.

Pain scores in the intent-to-treat analysis showed a significant improvement in all 3 groups compared with baseline at day 30, 91, and 182 (all p<0.001). In particular, the chondroitin sulfate and celecoxib groups showed a statistically greater reduction in pain compared with the placebo group (p=0.001 for chondroitin sulfate and p=0.009 for celecoxib) at 6 months. There was no significant difference in pain scores observed between the chondroitin sulfate and celecoxib groups.

In addition, both the chondroitin sulfate and celecoxib groups had significantly greater reductions in the Lequesne Index compared with placebo (p=0.023 for chondroitin sulfate and p=0.015 for celecoxib) at 6 months. Again, no difference was observed between the chondroitin sulfate and celecoxib groups for the Lequesne Index.

“We confirmed the excellent safety profile of CS that has been previously observed by others,” wrote Reginster and colleagues. “This compelling benefit-risk profile, in light of the known clinical risks associated with chronic usage of NSAIDs and paracetamol, underscores the potential importance of pharmaceutical-grade CS in the management of knee OA, especially in this older population requiring long-term treatment.”

Disclosures:

The study was sponsored by IBSA Institut Biochimique SA, Pambio-Noranco, Switzerland, a pharmaceutical company that markets chondroitin sulfate.

References:

Reginster JY, Dudler J, Blicharski T, Pavelka K. “Pharmaceutical-grade Chondroitin sulfate is as effective as celecoxib and superior to placebo in symptomatic knee osteoarthritis: the ChONdroitin versus CElecoxib versus Placebo Trial (CONCEPT).” Ann Rheum Dis. 2017 May 22. pii: annrheumdis-2016-210860. doi: 10.1136/annrheumdis-2016-210860. [Epub ahead of print]