We report on a female case of rheumatoid arthritis (RA) with hepatitis C virus comorbidity. The patient was treated once weekly over ten consecutive weeks with Adacolumn device. Clinical assessment and HCV-RNA concentration were monitored at weeks-1, 4, 9, 14 and during follow-up over 6 months. At the end of the treatment: the number of tender and swollen joints, patient's global assessment of disease activity (VAS), physician's VAS, C-reactive protein (CRP) decreased, respectively; ACR response was >20. This improvement was maintained for over 2 months. At week 38, the patient was re-treated achieving again an ACR response >20.