Prediction of response and adverse events to methotrexate treatment in patients with rheumatoid arthritis

Methotrexate is the disease-modifying antirheumatic drug of first choice for most patients with rheumatoid arthritis. Although methotrexate has been on the market for a few decades now, we are still unable to predict with great accuracy who will respond to methotrexate treatment and who will develop adverse events. A number of studies have identified several demographic, clinical and genetic factors associated with (non)-response or adverse events, but results are controversial. This paper describes the findings to date and possible explanations for the inconsistent findings.