In patients with psoriatic arthritis (PsA), cotreatment with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) and tumor necrosis factor inhibitors (TNFi), specifically methotrexate plus adalimumab or infliximab, is associated with improved remission rates, according to study results published in Annals of the Rheumatic Diseases.
Current treatment guidelines are limited regarding the cotreatment of PsA with TNFi and csDMARDs. The American College of Rheumatology (ACR) recommends first-line treatment with TNFi. In patients with a lack of response to csDMARDs, the ACR recommends switching to rather than adding a TNFi. The European Alliance of Associations for Rheumatology (EULAR) recommends csDMARDs as a first-line treatment and adding a TNFi if needed.
The current observational study included adult patients with PsA from 13 European rheumatology registers. Patients were initiated with TNFi treatment between 2006 and 2017. The researchers compared 1-year TNFi retention and remission by csDMARD cotreatment status and across countries. Subtypes of TNFi (adalimumab, infliximab, and etanercept) were also evaluated.
Of 15,332 patients, 9440 (62%) were in the cotreatment group and 5892 (38%) were in the TNFi monotherapy group. Among csDMARDs, methotrexate was most frequently used (79%). Retention of TNFi monotherapy and comedication treatment varied significantly across countries, precluding overall comparisons.
Less heterogeneity was noted across countries for remission. Combined data showed comedication was associated with improved remission (odds ratio [OR], 1.25; 95% CI, 1.12-1.41). Specifically, cotreatment of methotrexate was associated with improved remission for adalimumab (OR, 1.45; 95% CI, 1.23-1.72) and infliximab (OR, 1.55; 95% CI, 1.21-1.98), but not for etanercept (OR, 1.12; 95% CI, 0.95-1.31).
Limitations of the study included unknown between-country factors affecting retention rates, the use of 28-joint counts to define remission of PsA rather than 66/68-joint counts, potential misclassification of PsA, small sample sizes in some countries, potential confounding by different PsA disease states and other comorbidities, and the inability to consider changes in csDMARD treatment over the 1-year follow-up period.
The researchers concluded, “Our findings support the prevailing strategy, in a situation of incomplete response, to continue methotrexate therapy when commencing treatment with infliximab or adalimumab, while for etanercept methotrexate may be discontinued.”
Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.
Lindström U, Giuseppe DD, Delcoigne B, et al. Effectiveness and treatment retention of TNF inhibitors shen used as monotherapy versus comedication with csDMARDs in 15,332 patients with psoriatic arthritis. Data from the EuroSpA collaboration. Ann Rheum Dis. 2021;80:1410-1418. doi:10.1136/annrheumdis-2021-220097