SAN FRANCISCO, CA—“Real world” patients with rheumatoid arthritis treated with infliximab (IFX) or golimumab (GLM) have comparable retention rates, found authors of an analysis from a prospective observational Canadian registry, presented at the 2015 ACR/ARHP Annual Meeting.

“Gender, enrollment year, and to a lesser degree age, possibly signifying differences in patient preferences or changes over time in clinical practice, as well as Clinical Disease Activity Index (CDAI) score of 15 or less at 6 or 12 months were identified as significant independent predictors of long-term retention,” reported lead study author Edward C. Keystone, MD, of the University of Toronto/Rebecca MacDonald Centre for Arthritis and Autoimmune Disease in Toronto, Ontario, Canada, and colleagues.

Previously, differences in treatment retention between anti-tumor necrosis factor (TNF) agents have been reported, with some data suggesting that concomitant methotrexate use, for example, might improve retention.

To compare long-term retention of infliximab and golimumab and identify independent predictors of retention, the investigators analyzed data from 972 patients with RA enrolled in BioTRAC, an ongoing registry. Included were those treated with infliximab (enrolled since 2002) or golimumab (enrolled since 2010).

At baseline, most patients were female (76.3%); mean (standard deviation, SD) age was 55.9 (13.8) years, and disease duration was 8.6 (9.1) years. The majority (94.5%) was biologic naïve and being treated with infliximab (84.8%). Concomitant DMARDs had been administered to 88.5% of the patients at baseline and 35.9% had been treated with corticosteroids.

Mean disease parameters were CDAI, 35.3 (17.5); Health Assessment Questionnaire (HAQ), 1.6 (0.7); swollen joint count (0-28), 10.3 (6.8); tender joint count (0-28), 12.0 (7.9); patient global assessment (Visual Analog Scale [VAS] cm), 6.0 (2.5); and physician global (0-10 Numerical Rating Scale [NRS]), 6.4 (2.1), Dr. Keystone reported.

Of the patients, 600 (61.7%) received treatment for 18 months or more.

Univariate analysis identified potential predictors of retention to be age (odds ratio [OR], 95% confidence interval [CI] 0.99 (0.98, 1.00)], disease duration (0.97 [0.95, 0.99]), enrollment year (1.10 [(1.06, 1.15]), male gender (0.68 [0.50, 0.94]), golimumab vs. infliximab use (2.24 [1.58, 3.19]), biologic naiveté (0.58 [0.33, 1.01]), and baseline DMARD use (0.54 [0.36, 0.80]) (P<0.100).

No effect was observed for baseline corticosteroid use (0.86 [0.66, 1.13]), CDAI (1.00 [0.99, 1.00]),or HAQ [0.98 (0.81, 1.17)].

However, on multivariate analysis, only older age (0.98 [0.97, 1.00]) and male gender (0.50 [0.29, 0.85]) were found to be associated with significantly lower odds of treatment discontinuation, while “more recent enrollment year was associated with higher odds (1.36 [1.20-1.54]),” they reported.

Lower disease activity—defined as CDAI remission vs. low. vs. moderate vs. high—at 6 or 12 months “was associated with significantly (P<0.001) higher probability of long-term retention,” Dr. Keystone noted.

An ROC curve analysis identified a CDAI score of ≤15.7 (AUC=0.652) at 6 months (P<0.001) and a score of ≤14.6 (AUC=0.679) at 12 months (P<0.001) to be most accurate at predicting long-term retention of the anti-TNF agents, they concluded.