Old drugs, old problems: where do we stand in prediction of rheumatoid arthritis responsiveness to methotrexate and other synthetic DMARDs?

Table 3 Summary of nongenetic biomarkers of response to MTX and other DMARDs.

Factors	Predictors of response?k	Comments
RF	No	Some results confounded by its poor prognostic role; however, most evidence is clear in that it does not influence treatment response
ACPA	Not likely	More data needed but does not seem to predict response; associated with worse outcomes in some studies but may reflect more severe disease; interesting reports in UA, pending confirmation
Anti-MCV	Unknown	Suggested to relate to more severe disease; not yet addressed in terms of response to treatment
Creatinine clearance	No	Few studies analyzed this factor, no association with MTX response in a meta-analysis
Hb levels	Uncertain	Anecdotal reports of association with better response; needs confirmation and its role should be clarified in future studies
Cytokines	Uncertain	Small/pilot studies suggesting association with response; potential promising role of baseline TNF levels, TNFID₅₀ and IL-1ra/IL-1β ratio
Others	Uncertain	Other interesting factors analyzed in small studies and not further confirmed include MMP-3, urinary 7-OH-MTX and IgG hypogalactosylation

Conclusions and comments are based on the findings reported and discussed in the text. ACPA, anti-citrullinated protein antibodies; anti-MCV, anti-modified citrullinated vimentin antibodies; DMARDs, disease modifying anti-rheumatic drugs; Hb, hemoglobin; IgG, immunoglobulin G; IL-1ra, interleukin-1 receptor antagonist; IL-1β, interleukin-1β; MMP-3, matrix metalloproteinase-3; MTX, methotrexate; RF, rheumatoid factor; TNF, tumor necrosis factor; TNFID₅₀, dose required to suppress by 50% the production of tumor necrosis factor; UA, undifferentiated arthritis; 7-OH-MTX, 7-hydroxy-methotrexate.

ISSN: 1741-7015