Psoriatic arthritis patients who are taking a tumor necrosis factor inhibitor for the first time do about the same with or without the addition of methotrexate, Dr. Karen M. Fagerli said at the annual European Congress of Rheumatology.
Patients who received concomitant methotrexate, however, were more likely to still be taking that therapy after 3 years than were patients on anti-TNF monotherapy.
Dr. Karen M. Fagerli
Dr. Fagerli of the Diakonhjemmet Hospital, Oslo, and her colleagues presented new data on the impact of concomitant medication with methotrexate for psoriatic arthritis patients who are taking a TNF inhibitor for the first time. Although comedication with methotrexate is known to be helpful in rheumatoid arthritis and ineffective in ankylosing spondylitis, its value has been unclear when comes to psoriatic arthritis.
"The jury is very much still out on this," Dr. Fagerli said in an interview.
The new data indicate that the combination of methotrexate and a TNF inhibitor doesn’t have the same synergistic effect in psoriatic arthritis as it does in rheumatoid arthritis, but the fact that patients on combination therapy had superior drug survival indicates that there is a role for methotrexate with a TNF inhibitor, she said.
"We saw similar responses in patients with or without concomitant methotrexate. However, there were improved 3-year drug survival rates seen with concomitant methotrexate. This was most prominent in patients on infliximab, but there was no clear trend in patients receiving etanercept," she reported.
Figuring out exactly what that role is and which patients can most benefit from this combination of treatments will require more research. Examining the treatment effect in psoriatic arthritis is a growing area of study, Dr. Fagerli said, as more researchers look for effects specifically in that condition, rather than adopting practice from other diseases.
"I think this is really an emerging issue," Dr. Fagerli said.
In this study, the researchers analyzed data from the NOR-DMARD register, a repository of data on adult patients with inflammatory arthropathies who are starting a new DMARD (disease-modifying antirheumatic drug) treatment. The register, which began in 2000, includes patients consecutively from across five rheumatology departments in Norway. The current analysis included 370 psoriatic arthritis patients who were being treated with their first TNF inhibitor. The patients were receiving either combined treatment with methotrexate or were not receiving a concomitant DMARD.
At 3 months, there was very little difference in either the state of disease or the change from baseline between the two groups. The researchers considered responses on the patient and physician global assessments and the Modified Health Assessment Questionnaire and SF-6D health status instruments. However, there was an improved 3-year drug survival in the group receiving combination treatment.
Dr. Fagerli reported that she has received speakers honoraria from Abbott, MSD, Pfizer, and Roche.