Pain Reduction With Oral Methotrexate in Knee Osteoarthritis

BACKGROUND: Treatments for osteoarthritis (OA) are limited. Previous small studies suggest that the antirheumatic drug methotrexate may be a potential treatment for OA pain. OBJECTIVE: To assess symptomatic benefits of methotrexate in knee OA (KOA). DESIGN: A multicenter, randomized, double-blind, placebo-controlled trial done between 13 June 2014 and 13 October 2017. (ISRCTN77854383; EudraCT: 2013-001689-41). SETTING: 15 secondary care musculoskeletal clinics in the United Kingdom. PARTICIPANTS: A total of 207 participants with symptomatic, radiographic KOA and knee pain (severity ≥4 out of 10) on most days in the past 3 months with inadequate response to current medication were approached for inclusion. INTERVENTION: Participants were randomly assigned 1:1 to oral methotrexate once weekly (6-week escalation 10 to 25 mg) or matched placebo over 12 months and continued usual analgesia. MEASUREMENTS: The primary end point was average knee pain (numerical rating scale [NRS] 0 to 10) at 6 months, with 12-month follow-up to assess longer-term response. Secondary end points included knee stiffness and function outcomes and adverse events (AEs). RESULTS: = 0.008). Treatment adherence analysis supported a dose-response effect. Four unrelated serious AEs were reported (methotrexate: 2, placebo: 2). LIMITATION: Not permitting oral methotrexate to be changed to subcutaneous delivery for intolerance. CONCLUSION: Oral methotrexate added to usual medications demonstrated statistically significant reduction in KOA pain, stiffness, and function at 6 months. PRIMARY FUNDING SOURCE: Versus Arthritis.