Background Combination therapy with biologics and synthetic disease-modifying antirheumatic drugs (sDMARD) is the standard treatment in patients with rheumatoid arthritis (RA) in which biologics are indicated. However, this is not always the case in daily clinical practice. The reasons and profile of patients on monotherapy have been poorly explored.
Objectives To analyze the profile of RA patients treated with biologics in monotherapy and compare it with the standard combination treatment.
Methods An observational cross-sectional study was conducted. Drug dispensation databases and patient clinical records from a tertiary hospital were reviewed. Patients with a clinical diagnosis of RA on any biologic in 2013 were selected for analysis. Demographic and clinical characteristics (age, gender, disease duration, rheumatoid factor status), reason for monotherapy and combination therapy with sDMARD were studied. Statistical comparison was performed by T-test and Chi-squared test. Disease activity was measured by DAS28 and multivariate analysis was used to evaluate the impact of individual parameters on DAS28.
Results The analysis included 268 patients with RA treated with biologics. Monotherapy accounted for 11.2% of all patients. Patients on monotherapy showed a tendency without statistical significance to longer disease duration compared with combination therapy [15.8 (12.1) vs 13.6 (8.8); *p>0.05], similar age 62.6 (14.5) vs 62.1 (12.6), gender (female 90.0% vs 82.7%), and positive rheumatoid factor (77.8% vs 73.2%). Monotherapy was more frequent as third or later line of biological therapy (24.1% vs 8%; p<0.05). Among patients on monotherapy, Tocilizumab was the most frequently used agent (30%). Regarding to each individual biologic, monotherapy was more frequent in Tocilizumab (36%), and Abatacept (17.4%) than in anti-TNF (7-10%) patients. Reasons for monotherapy were sDMARD intolerance (60.9%) and contraindications (39.1%), such as lung disease (21.7%), liver disease (8.7%), neutropenia (4.3%), and pregnancy (4.3%). DAS28 was non-significantly greater in monotherapy than in combined therapy (p>0.05). Multivariate analysis showed higher DAS28 for third line or later biologic treatment but not for monotherapy (p=0.004).
Conclusions Biologic monotherapy in RA is related to third or later line of treatment in clinical practice, being Tocilizumab the most frequently used medication for these patients.
Disclosure of Interest None declared