Long-Term Survival of Subcutaneous Biosimilar Tumor Necrosis Factor Inhibitors Compared to Originators: Results From a Multicenter Prospective Registry.

OBJECTIVE: To analyze the long-term survival of subcutaneous biosimilar tumor necrosis factor inhibitors compared to the originator molecules in patients with rheumatic diseases, as well as the factors associated with drug discontinuation. METHODS: Retrospective analysis of BIOBADASER, the Spanish multicenter prospective registry of patients with rheumatic disease receiving biologic and targeted disease-modifying antirheumatic drugs. Patients who started etanercept (ETN) or adalimumab (ADA) from January 2016 to October 2023 were included. The survival probabilities of biosimilars and originators were compared using Kaplan-Meier estimating curves. To identify factors associated with differences in the retention rates, hazard ratios (HR) were estimated using Cox regression models for all and specific causes (inefficacy or adverse events [AEs]) of discontinuation. RESULTS: A total of 4162 patients received 4723 treatment courses (2991 courses of ADA and 1732 courses of ETN), of which 722 (15.29%) were with originator molecules and 4001 (84.71%) were with biosimilars. The originators were more frequently discontinued than biosimilars (53.32% vs 33.37%, respectively). The main reason for discontinuation was inefficacy (60.35% of the treatments). The risk of overall discontinuation was lower for biosimilars (adjusted HR 0.84, 95% CI 0.75-0.95). Female sex, obesity, and second or later treatment lines increased the risk of discontinuation, whereas disease duration and the use of concomitant methotrexate were associated with a greater survival. When assessing cause-specific reasons of discontinuation, excluding nonmedical switching, the results from the crude and adjusted analyses showed no significant differences in the retention rate between biosimilars and originators. CONCLUSION: No significant differences were found between treatments in long-term survival due to inefficacy or AEs.

Anti-TNFα drug levels in patients with rheumatoid arthritis and spondyloarthritis.

BACKGROUND AND OBJECTIVES: Knowledge of the levels of anti-TNFa drugs can modify treatment in patients with rheumatoid arthritis (RA) and spondyloarthritis (SpA). OBJECTIVES: To compare the levels of anti-TNFa in patients with RA vs SpA, in different clinical situations. MATERIALS AND METHODS: A retrospective, observational study was conducted. Levels of anti-TNFa and the presence of anti-drug antibodies were measured in consecutively selected patients, using the ELISA technique. RESULTS: Fifty-three, 73 and 78 patients treated with infliximab, adalimumab and etanercept were studied, respectively. The median drug levels in patients using standard doses were infliximab 2.2 µg/mL (1.4-5.2), adalimumab 4.9 µg/mL (0.8-8.9) and etanercept 3.1 µg/mL (2.3-4.4). There were no differences in drug levels according to disease activity but we found differences in etanercept and infliximab levels according to DMARD use. CONCLUSIONS: Levels of anti-TNFa drugs will change with DMARD treatment.

Anti-TNFα Drug Levels in Patients with Rheumatoid Arthritis and Spondyloarthritis. / Niveles de fármacos anti-TNFα en pacientes con artritis reumatoide y espondiloartritis.

BACKGROUND AND OBJECTIVES: Knowledge of the levels of anti-TNFα drugs can modify treatment in patients with rheumatoid arthritis (RA) and spondyloarthritis (SpA). OBJECTIVES: To compare the levels of anti-TNFα in patients with RA vs SpA, in different clinical situations. MATERIALS AND METHODS: A retrospective, observational study was conducted. Levels of anti-TNFα and the presence of anti-drug antibodies were measured in consecutively selected patients, using the ELISA technique. RESULTS: Fifty-three, 73 and 78 patients treated with infliximab, adalimumab and etanercept were studied, respectively. The median drug levels in patients using standard doses were infliximab 2.2µg/ml (1.4-5.2), adalimumab 4.9µg/ml (0.8-8.9) and etanercept 3.1µg/ml (2.3-4.4). There were no differences in drug levels according to disease activity but we found differences in etanercept and infliximab levels according to DMARD use. CONCLUSIONS: Levels of anti-TNFα drugs will change with DMARD treatment.

[Tumour necrosis factor alpha antagonists in established rheumatoid arthritis: effectiveness comparative study]. / Estudio comparativo de efectividad de los inhibidores del factor de necrosis tumoral alfa en la artritis reumatoide establecida.

BACKGROUND AND OBJECTIVE: Knowing the differences in the effectiveness between three tumour necrosis factor alpha antagonists (anti-TNF alpha) in rheumatoid arthritis (RA) has important clinical implications. The aim of this study was to assess anti-TNF alpha effectiveness and to study possible differences in outcomes between them. PATIENTS AND METHOD: We included all patients with rheumatoid arthritis (RA) attended in consulting room from Zaragoza Area II between May 2000 and December 2006 who completed a year with anti-TNF alpha treatment. Several demographic and clinical parameters at the beginning and after a year with three different agents were analysed and compared. RESULTS: 119 patients completed a year with anti-TNF alpha, 28 with infliximab, 44 with etanercept and 37 with adalimumab. After a year with treatment, DAS 28 descended 1,82 (1,42) points and HAQ 0,3 (0,58) (p<0,05). Comparing the clinical parameters after a year DAS 28 was 3,8 in the three groups. HAQ was 1,2 for patients in treatment with infliximab and 0,9 for patients with etanercept and adalimumab. There were no significant differences in effectiveness between the 3 drugs. CONCLUSIONS: Anti-TNF alpha drugs are effective to treat RA and the effectiveness is similar in all them.