Investigation on the Middle Size Molecule Elimination Characteristics of the FXCorDiax 100 in Relation to the FX 100 and the Polyflux 210 H Dialyser

Inclusion Criteria: * hemodialysis patients 18 years and older * treated by post dilution on-line Hemodiafiltration (HDF) for at least one month * who reached a dialysis dose (Kt/V) of at least 1.2 at each of the last two monthly checks * who are on a stable anticoagulation and anemia management * whose hemoglobin is between 10.5 and 13.0 g/dl * who are clinically stable based on judgment of nephrologist * who are on a regular thrice weekly HDF schedule, e.g. Monday-Wednesday-Friday or Tuesday-Thursday-Saturday, * who have a good vascular access (fistula or graft) which enables easy insertion of the needles and suitable effective blood flow (\> 300 ml/min) * who are able to understand the nature and requirements of the clinical investigation and who have given written informed consent Exclusion Criteria: Patients * with active Hepatitis B, Hepatitis C or HIV infection * who are severely malnourished as judged by the principal investigator * who are known or suspected to have allergy to the trial products or related products * with a central venous catheter based vascular access * who are abusing non-legal drugs or alcohol * who have currently active malignant disease * who are female of child-bearing age without effective measures of contraception, pregnant or breastfeeding * who participate simultaneously in another clinical investigation * who have participated in othe clinical investigations during the last month * who are uncooperative