Chondroitin Rivals Celecoxib for Osteoarthritis Symptoms

Laird Harrison

November 10, 2015

SAN FRANCISCO — Chondroitin, typically considered more a nutritional supplement than a treatment option, can slow the long-term progression of knee osteoarthritis while matching the symptom relief of celecoxib, an eyebrow-raising study presented here at the American College of Rheumatology 2015 Annual Meeting has found.

"This is quite significant," said presenter Jean-Pierre Pelletier, MD, from the division of rheumatology at the University of Montreal.

Researchers have long debated the effectiveness of chondroitin, which is derived from sources such as beef and shark cartilage, for the treatment osteoarthritis. In the United States, it is sold as a nutritional supplement; in Europe, it is sometimes prescribed as a pharmaceutical.

To assess the effectiveness of chondroitin, Dr Pelletier and his team recruited 194 patients with primary knee osteoarthritis.

All had radiographic evidence of Kellgren–Lawrence grade 2 or 3, signs of synovitis, and a minimum joint space width of at least 2 mm in the medial femorotibial compartment evident on standing knee x-ray. And all had knee pain for the previous month and a visual analogue scale (VAS) score of pain while walking of at least 40 mm.

Half the patients were randomized to receive pharmaceutical-grade chondroitin sulphate (Condrosan, Bioibérica) 1200 mg daily. The other half, who served as the control group, were randomized to receive celecoxib (Celebrex, Pfizer) 200 mg daily.

Patients at risk for cardiovascular or gastrointestinal events were excluded from the analysis because of the fear that celecoxib would trigger such an event.

All patients were allowed acetaminophen, up to 3 g per day, as a rescue medication.

Changes in Cartilage

The researchers chose celecoxib rather than a placebo because it has been shown to relieve symptoms but does not have any effect on the structure of the knee in osteoarthritis. It was important to provide some pain relief so the patients in the control group would stay in the study, Dr Pelletier explained.

The two groups were similar in sex, age, pain, and body mass index. They were also similar in pain, stiffness, and physical function, measured on the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index and the VAS. Average age was 61 years, and average BMI was 31 kg/m².

Over the 2-year study period, the number of patients who dropped out because of lack of efficacy, adverse events, loss to follow-up, protocol violation, and miscellaneous other problems was similar in the two groups. In the final analysis, there were 58 in the chondroitin group and 63 patients in the control group.

The researchers used MRI to measure changes in the cartilage and other structural elements of the knees. After 12 months, a difference in cartilage loss in the medial compartment emerged between the two groups, which persisted out to 24 months.

"Chondroitin sulfate was significantly better at reducing cartilage loss, and both treatments were found to be equally effective at reducing symptoms over time," Dr Pelletier reported.

Table. Two-Year Outcomes

Outcome Chondroitin Group Celecoxib Group P Value
Global knee cartilage loss, % –5.76 –6.51 .054
Medial compartment cartilage loss, % –6.69 –8.14 .013
Synovial fluid volume change, mL –3.86 –2.13 .494
WOMAC pain change, % –46.4 –53.0 .415
VAS pain change, % –49.2 –55.4 .439


Although there was no overall difference between the two groups in the thickness of the synovial membrane, there was a marked reduction in synovial thickness in a subgroup of the chondroitin patients, said Dr Pelletier.

But chondroitin sold as a nutritional supplement might not provide the same benefits as the pharmaceutical-grade chondroitin used in the study, he cautioned.

Dr Pelletier said he is already using chondroitin in osteoarthritis. He typically starts with a "soft" drug, such as acetaminophen, and if that doesn't work, he progresses to chondroitin and glucosamine, he told Medscape Medical News.

If these treatments don't produce satisfactory results, he tries short-term treatment with nonsteroidal anti-inflammatory drugs to control spikes in pain.

The evidence is equivocal.

However, it might be too early to recommend the use of chondroitin, said session moderator Kelli Allen, PhD, from the University of North Carolina at Chapel Hill.

This study has not yet passed the scrutiny of a peer-reviewed journal, and must be balanced against negative outcomes in other chondroitin trials, she said. "The evidence is equivocal."

American College of Rheumatology (ACR) 2015 Annual Meeting: Abstract 950. Presented November 8, 2015.


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