Published online Jul 12, 2015. doi: 10.5499/wjr.v5.i2.108
Peer-review started: June 29, 2014
First decision: Steptember 27, 2014
Revised: October 24, 2014
Accepted: October 31, 2014
Article in press: November 3, 2014
Published online: July 12, 2015
AIM: To evaluate the effectiveness of the biological disease-modifying antirheumatic drugs (bDMARD) in the treatment of rheumatoid arthritis through a systematic review of observational studies.
METHODS: The studies were searched in the PubMed, EMBASE, Cochrane Controlled Trials Register and LILACS databases (until August 2014), in the grey literature and conducted a manual search. The assessed criteria of effectiveness included the EULAR, the disease activity score (DAS), the Clinical Disease Activity Index, the Simplified Disease Activity Index, the American College of Rheumatology and the Health Assessment Questionnaire. The meta-analysis was performed with Review Manager® 5.2 software using a random effects model. A total of 35 studies were included in this review.
RESULTS: The participants anti-tumor necrosis factor inhibitors (TNF) naïve, who used adalimumab (P = 0.0002) and etanercept (P = 0.0006) exhibited greater good EULAR response compared to the participants who used infliximab. No difference was detected between adalimumab and etanercept (P = 0.05). The participants who used etanercept exhibited greater remission according to DAS28 compared to the participants who used infliximab (P = 0.01). No differences were detected between adalimumab and infliximab (P = 0.12) or etanercept (P = 0.79). Better results were obtained with bDMARD associated with methotrexate than with bDMARD alone. The good EULAR response and DAS 28 was better for combination with methotrexate than bDMARD monotherapy (P = 0.03 e P < 0.00001). In cases of therapeutic failure, the participants who used rituximab exhibited greater DAS28 reduction compared to those who used anti-TNF agents (P = 0.0002). The participants who used etanercept achieved greater good EULAR response compared to those who did not use that drug (P = 0.007). Studies that assessed reduction of the CDAI score indicated the superiority of abatacept over rituximab (12.4 vs +1.7) and anti-TNF agents (7.6 vs 8.3). The present systematic review with meta-analysis found that relative to anti-TNF treatment-naïve patients, adalimumab and etanercept were more effective when combined with methotrexate than when used alone. Furthermore, in case of therapeutic failure with anti-TNF agents; rituximab and abatacept (non anti-TNF) and etanercept (as second anti-TNF) were more effective. However, more studies of effectiveness were found for the rituximab.
CONCLUSION: The best treatment for treatment-naïve patients is adalimumab or etanercept combined with methotrexate. For anti-TNF therapeutic failure, the best choice is rituximab, abatacept or etanercept.
Core tip: Rheumatoid arthritis is a chronic, progressive, systemic inflammatory disease that preferentially affects the synovial membranes of joints, eventually leading to bone and cartilage destruction. Its worldwide prevalence is estimated to be 0.3% to 1%. Observational studies could provide relevant information for deciding the choice of treatments, the elaboration of clinical protocols, and the formulation of health policies. The present systematic review of biological disease-modifying antirheumatic drugs included cohort observational studies that reported treatment results applied in real-life conditions; thus, these studies are able to fill in gaps in knowledge left by clinical trials.