The purpose of the study is to show equivalent performance of the Revaclear dialyzer when compared to a dialyzer with larger membrane surface area.

Study design: open, randomized, cross-over, multicentric, controlled prospective

Medical devices: Revaclear 200 versus FX 60 or Revaclear 400 versus FX 100, depending on patient needs

Patients/sample size: 30 adult chronic hemodialysis patients

Treatment: Each patient will be treated by hemodialysis for one week (3 dialysis sessions) with Revaclear dialyzers and one week (3 dialysis sessions) with FX dialyzers.

Objectives: intraindividual comparison of dialysis dose; reduction rates and total removal of urea, phosphate, creatinine and ß2-microglobulin; albumin loss

Primary variable: dialysis dose Kt/V urea

Secondary variable: reduction rates and total removal of urea, phosphate, creatinine and ß2-microglobulin

Safety variable: albumin loss, blood count

Inclusion Criteria:

• chronic renal failure and stable treatment with hemodialysis or hemodiafiltration for at least 3 months
• patients aged 18 years or more
• written consent to participate in the study (informed consent)
• dialysis via native fistula or Gore-Tex graft capable of providing a blood flow rate of at least 300 mL/min

Exclusion Criteria:

• single-needle dialysis
• pregnant and lactating women
• participation in other interventional studies less than 3 months prior to study start
• non-compliance with the dialysis prescription
• hematocrit less than 28%
• hospitalization
• antibiotic therapy
• active infection
• active cancer
• known positive serology for HIV, hepatitis B or C
• serious hemostasis disorders
• any comorbidity possibly conflicting with the study purpose or procedures