Effective tumour necrosis factor-blocking therapy reduces reactive oxygen metabolite level in rheumatoid arthritis

OBJECTIVE To assess circulating levels of derived reactive oxygen metabolites (ROMs) in patients with active rheumatoid arthritis (RA), before and during antitumour necrosis factor (TNF)-α therapy. METHODS Patients with active RA and failed previous treatment with disease-modifying antirheumatic drugs received subcutaneous anti-TNF-α for 52 weeks. Circulating hydrogen peroxide was quantified as a marker of oxidative stress at baseline and at 24 and 52 weeks. RESULTS The study included 40 patients. Circulating dROM levels were significantly reduced compared with baseline after 24 and 52 weeks' of anti-TNF-α treatment (33.2 ± 10.0 mgH2O2/dl, 29.5 ± 7.0 mgH2O2/dl and 29.3 ± 9.0 mgH2O2/dl, respectively). There was a significant direct correlation between disease activity score and ROM levels. CONCLUSION TNF-α inhibition can control disease activity and reduce circulating levels of reactive oxygen species in patients with RA.