Objectives To assess the efficacy of methotrexate (MTX) in decreasing pain and inflammation in symptomatic knee osteoarthritis (OA).
Methods One hundred and forty-four patients with primary knee OA were randomised in a 1:1 ratio to receive up to 25 mg/week oral MTX (n=72) or placebo (n=72) for 28 weeks. Outcome measures included reduction in pain and inflammation and improvements in physical function scores. Pain was assessed using the visual analogue pain scale, (VAS, 0–100 mm). Functional assessment was performed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and activities of daily living (ADL) scores. Synovitis was detected clinically and by ultrasound imaging at baseline and at the end of the study.
Results There was a clinically relevant reduction in the intervention group compared with the placebo group for knee pain, physical function and ADL scores at 28 weeks. The mean difference between treatment arms (95% CI) was 11.4 (2.8 to 20.0), p=0.009; 9.5 (3.7 to 15.3) p=0.001 and 1.2 (0.1 to 2.3), p=0.032, respectively. Furthermore, a clinically relevant reduction in synovitis (both clinically and by ultrasound) was noted in the MTX group compared with the placebo group at 28 weeks. The proportion of patients who had a reduction in VAS of >20 mm was significantly higher in the MTX group (n=38) 53% than in the placebo group (n=17) 24%, p=0.018.
Conclusions MTX significantly reduced pain and improved synovitis. There was a significant improvement in physical function. MTX may be a therapeutic option in the treatment of pain and inflammation related to knee OA.
Trial registration number: NCT01927484