Background/Purpose: Real-world data on adherence to TNFα inhibitors in patients with RA are missing from many regions, including the Middle East. This study evaluated the real-world 1- and 5-year adherence to etanercept (ETN) among Iraqi patients with RA.

Methods: This observational, retrospective study assessed patient data entered in the National Center of Rheumatology in Iraq database during the period May 2012 – May 2017. Individuals aged >18 years, with a diagnosis of RA, and who required treatment with ETN, with or without MTX, were identified and included in the analysis. Those previously treated with a different biologic or who were enrolled in a randomized clinical trial were excluded. Adherence was assessed for 1- and 5-year periods, with 1-year adherence defined as 7 consecutive patient visits. Demographics, Disease Activity Score 28 (DAS28), Clinical Disease Activity Index (CDAI) scores, and adverse events (AEs) data were also collected. Editorial support was provided by Charlene Rivera, PhD, and Vojislav Pejovic, PhD, of Engage Scientific Solutions and was funded by Pfizer.

Results: In total, data from 1293 individuals were collected. Approximately half (51.7%, n=668) were treated concomitantly with MTX and 40.4% were taking prednisolone. At baseline, the mean (± standard deviation) disease duration was 10.0 ± 8.3 years, and mean CDAI and DAS28 scores were 27.6 ± 13.0 and 5.7 ± 2.0, respectively. The adherence to treatment at 1 year was 86.5% (n=1119) for all patients and 85.5% (n=571) for those also receiving MTX. Among patients who discontinued treatment at 1 year, 75.2% (n=112) did not specify a reason, 20.8% (n=31) reported lack of efficacy, and 4.0% (n=6) reported side effects as reasons for discontinuation. Patients who discontinued treatment at 1 year due to side effects or other unspecified reasons had significantly improved CDAI and DAS28 scores at the last follow-up visit compared with baseline scores (16.3 and 19.9 vs 26.3 and 26.3 for CDAI, respectively; 4.5 and 4.8 vs 5.4 and 5.5 for DAS28, respectively; p≤0.001). The adherence at 5 years was 61.3% (50.4% for patients treated concomitantly with MTX). Among patients who discontinued treatment at 5 years, 84.6% did not specify a reason, 12.2% reported lack of efficacy, and 3.2% reported side effects as reasons for discontinuation. Average CDAI and DAS28 scores significantly decreased at the last follow-up visit compared with baseline among patients still on treatment at 5 years (19.9 vs 26.6 and 4.7 vs 5.6, respectively; p=0.001).

Conclusion: A majority of real-world Iraqi patients with RA were adherent to ETN treatment after 5 years. Furthermore, most patients tolerated treatment with ETN and had significant improvements in treatment scores at 5 years. Adherence was higher among patients in the total population compared with the subset receiving concomitant MTX.

ACR Meeting Abstracts - https://acrabstracts.org/abstract/adherence-of-etanercept-in-iraqi-patients-with-rheumatoid-arthritis-one-and-five-year-data-from-a-local-registry/