Methotrexate therapy in rheumatoid arthritis after failure to sulphasalazine: to switch or to add?

MTX, either alone or in combination with SSZ, is effective in the treatment of RA. Trials have shown that, after SSZ failure, the addition of MTX to SSZ is more effective than a switch to MTX. Whether this is also the case in daily practice has not been analysed yet. In this study, we compared the efficacy of a switch to MTX monotherapy with that of the addition of MTX to SSZ in the daily clinical practice of RA patients who had failed SSZ monotherapy in the Nijmegen RA Inception Cohort.

For this study, 230 patients who failed to SSZ monotherapy were followed for up to 52 weeks. A total of 124 underwent a switch to MTX alone, whereas 106 patients received the combination of MTX and SSZ. The primary outcome measure was the mean change in the disease activity score (DAS28) after 24 weeks.

Both treatment groups showed a significant decrease in DAS28 after 24 weeks, which was similar in both groups. Drug survival analysis showed that the chance to stop with a DMARD within 52 weeks was higher in the MTX-SSZ group (P <0.01).

In RA patients who failed to SSZ the clinical efficacy of a switch to MTX monotherapy was similar to that of the addition of MTX, suggesting that in daily clinical practice a switch to MTX is a good option for patients with an inadequate response to SSZ.