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.