Clinical efficacy and safety of glucosamine, chondroitin sulphate, their combination, celecoxib or placebo taken to treat osteoarthritis of the knee: 2-year results from GAIT

Sawitzke AD, Shi H, Finco MF, et al. · Annals of the Rheumatic Diseases

Over two years no arm, including celecoxib, beat placebo on WOMAC pain or function. The odds of a 20% WOMAC pain response against placebo were 1.21 for celecoxib (95% CI 0.71 to 2.07), 1.16 for glucosamine (0.65 to 2.04), 0.83 for the combination (0.51 to 1.34) and 0.69 for chondroitin alone (0.40 to 1.21) — every interval spanning 1. The moderate-to-severe pain subgroup that appeared to favour the combination in the original GAIT report was tested here as a treatment interaction, and none of those interactions was significant.

Population

GAIT participants with knee OA who continued blinded treatment for 2 years

Intervention

Glucosamine HCl 1500 mg/day, chondroitin 1200 mg/day, both, or celecoxib for 24 months

Comparator

Placebo

Limitations

Substantial dropout from the original cohort; wide confidence intervals mean modest effects cannot be fully excluded. Rescue paracetamol use ran lowest in the celecoxib arm (465 mg/day) and highest on placebo (645 mg/day), in the same rank order as the primary outcome, so some of the flat result may sit in the rescue medication rather than in the treatments.