EFFECTS OF METHOTREXATE ON EXTRACELLULAR MATRIX AND TISSUE INFLAMMATION BIOMARKERS IN PEOPLE WITH KNEE OSTEOARTHRITIS

Purpose: Inflammation is highly prevalent in OA and is associated with pain. In inflammatory arthritides such as rheumatoid arthritis, methotrexate (MTX) is the gold standard treatment for synovitis and has a well-known, acceptable toxicity profile. The Pain Reduction with Oral Methotrexate in knee Osteoarthritis, a pragmatic phase III trial of Treatment Effectiveness (PROMOTE) trial showed significant pain reduction in response to MTX compared to placebo. Here we investigate the effect of MTX on tissue remodelling by measuring blood-based extracellular matrix markers reflecting aggrecan (ARGS), type I and III collagen degradation (C1M, C3M), as well as tissue inflammation with C-reactive protein metabolite (CRPM).