Background Etanercept (ETN) is an established bDMARDs for therapy of rheumatoid arthritis and some other inflammatory diseases. In rheumatoid arthritis patients ETN could be given in combination therapy with sDMARDs as well as in monotherapy.
Objectives To investigate and compare etanercept monotherapy versus combination with sDMARDs in RA patients regarding survival on drug, efficacy, quality of life and reason for discontinuation.
Methods Observational, open, long-term study of patients from the ATTRA registry starting the ETN therapy since 2010 either on monotherapy or in combination with sDMARDs (n=605). 461 patients (80.7%) were females, rheumatoid factor was positive in 429 (76.6%), anti CCP antibodies in 412 (74.5%) patients. The following groups of patients were assessed: Etanercept monotherapy (ETN-mono, n=83), combination with methotrexate (Combo-MTX, n=378), combination with other sDMARDs (Combo-other sDMARDs, n=110).
Mean ± SD and absolute/relative frequencies were used to describe continuous and categorical variables, respectively. P-value of Pearson Chi-square test and Kruskal-Wallis test is given when assessing differences between groups in categorical and continuous variables. Results are presented as hazard ratio (HR) with corresponding p-value. Statistical evaluation was processed by IBM SPSS Statistics ver. 24.
Results In the first measurement of activity after 3 months, there were significantly lower disease activity in both Combo groups compared to ETN mono (3.2±0.1 resp. 2.9±0.1 versus 3.7±0.2, p<0.001). However since the month 6 the differences lost their significance and the disease activity were comparable in all groups up to the month 24.
The HAQ value was significantly higher already at the time of ETN onset at month 0 in the ETN-mono group (1.7 versus 1.4 resp. 1.5, p<0.001) and stayed significantly higher at the month 3 and 12.
The hazard ratio (HR) for ETN discontinuation was higher in ETN mono group compared to Combo-MTX (HR=1.330) and also compared to Combo-other sDMARDs (HR=1.098), even if the differences did not reach statistical significance (p=0.131, resp. 0.671). Similar trend was evident, if the etanercept was given in the first and any subsequent line of biological therapy. The HR for ETN discontinuation was also numerically higher in Combo-other sDMARDs than in Combo MTX group (HR=1.211, p=0.244).
The patients on ETN mono have higher risk of discontinuation due to inefficacy compared to Combo-MTX (HR=1.415) and also to Combo-other sDMARDs (HR=1.670). The patients of combo-other sDMARDs group had lower risk of discontinuation due to inefficacy also in comparison with combo-MTX (HR=0.847). None of the differences reach statistical significance.
The patients on ETN mono have higher risk of discontinuation due to adverse event compared to Combo-MTX and also to Combo-other sDMARDs. This trend is higher, if ETN is given in the subsequent line of biological therapy, but not in first line. Nevertheless like in other situations, the differences showed some trend, but were not statistically significant.
Conclusions Results support the evidence of advantages of ETN combination with methotrexate – quicker onset of efficacy and give some evidence of better survival on etanercept therapy in combination with methotrexate.
Acknowledgements Supported by AZV 15–28659A
Disclosure of Interest None declared