%0 Journal Article %A Berthold, E %A Månsson, B %A Gullstrand, B %A Geborek, P %A Saxne, T %A Bengtsson, AA %A Kahn, R %D 2017 %T Tumour necrosis factor-α/etanercept complexes in serum predict long-term efficacy of etanercept treatment in seronegative rheumatoid arthritis %U https://tandf.figshare.com/articles/journal_contribution/Tumour_necrosis_factor-_etanercept_complexes_in_serum_predict_long-term_efficacy_of_etanercept_treatment_in_seronegative_rheumatoid_arthritis/4986371 %R 10.6084/m9.figshare.4986371.v1 %2 https://tandf.figshare.com/ndownloader/files/8393900 %K drug survival %K seronegative RA %K biological-na ïve adults %K 129 seropositive RA %K serum %K 6  week follow-up %K 145 biological-na ïve patients %K etanercept %K TNF -α %K enzyme-linked immunosorbent assay %K tumour necrosis factor -α %K drug survival time %X

Objective: To study whether serum levels of tumour necrosis factor-α (TNF-α), free or bound to etanercept, in biological-naïve adults with rheumatoid arthritis (RA) could predict the long-term efficacy of etanercept, measured as drug survival.

Method: We identified 145 biological-naïve patients with RA starting treatment with etanercept at the Department of Rheumatology, Skåne University Hospital (1999–2008), of whom 16 had seronegative and 129 seropositive RA. TNF-α in serum was quantified using enzyme-linked immunosorbent assay in samples from the onset of treatment and at 6 week follow-up. Drug survival time was used to evaluate the long-term efficacy of etanercept.

Results: Levels of TNF-α were significantly increased at follow-up compared to at the start. At the 6 week follow-up, circulating TNF-α mainly comprised TNF-α in complex with etanercept. Longer drug survival time correlated with increased TNF-α at 6 week follow-up in the patients with seronegative RA, but not in the seropositive patients.

Conclusion: We demonstrated that levels of circulating TNF-α increased in almost all individuals after initiation of treatment with etanercept and that this increase mainly comprised TNF-α in complex with etanercept. More importantly, this increase may predict drug survival in adults with seronegative, but not seropositive, RA and suggests that measuring TNF-α/etanercept complexes in serum may be relevant in patients with seronegative RA.

%I Taylor & Francis