Predicting treatment success in early RA: can biomarkers predict methotrexate response?

This study investigated if biomarkers (BMs) can predict the response to methotrexate (MTX) in early rheumatoid arthritis (RA).

They found that the level of BMs at baseline could predict the success of MTX treatment.

Rheumatoid arthritis (RA) is a condition caused by inflammation. This leads to painful swelling in the joints. RA is treated with medication to reduce inflammation. As RA is a long-term condition, the aim of treatment is to reduce symptoms. The goal of treatment is to achieve low disease activity (LDA) or remission (no symptoms). 

Methotrexate( MTX) is the first-line of treatment for RA. MTX suppresses inflammation in a number of ways. The majority of patients with RA (60-70%) do not achieve LDA with MTX. There are a number of factors that affect MTX response. Smoking is one factor that negatively impacts MTX treatment. Some studies suggest that measuring proteins in the blood might help predict the response to MTX. Proteins that can be used to predict outcomes are called biomarkers (BMs). In, RA certain proteins are indicators of inflammation. It is unclear if BMs can predict the response to MTX treatment in early RA.

This study included 298 patients with early RA. Patients were assigned to MTX therapy for 3 months initially. Blood samples were taken at the beginning and at follow-up. A series of 12 BMs were measured. These included C-reactive protein (CRP), leptin, tumor necrosis factor receptor 1 (TNF-R1) and vascular cell adhesion molecule 1 (VCAM-1). Disease activity was measured using the Disease Activity Score (DAS28).

After 3 months, 34.9% (104) of patients achieved LDA. Patients with lower levels of CRP and leptin at the beginning were more likely to achieve LDA with MTX (40% vs 23-25%). Patients with higher levels of TNF-R1 and VCAM-1 at the beginning were more likely to achieve LDA with MTX (43-41% vs. 27-25%). Patients with a combined score from these BMs had a 55% reduced chance of achieving LDA. 

The authors concluded that the level of BMs at baseline could predict the success of MTX treatment in patients with early RA.

There was variability in BM levels. These BMs will need to be validated in other groups of patients with RA to confirm the findings. 

If you have any concerns regarding rheumatoid arthritis treatment, please consult with your physician.