A clinical study for FS-501 (hollow fiber dialyzer)

INTERVENTION: Dialyze using FS‐501 (FS‐501BG or FS‐501BK) for two weeks. CONDITION: Renal failure PRIMARY OUTCOME: 1)Adverse events(from the first investigational device use to right before using the other approved hemodialyzer or hemodiafilter); 2)Device problems (from the day of investigational devices receipt to the day of Investigational devices return); 3)Blood compatibility (change of a white blood‐cell count and platelets count during the hemodialysis) (Once on any given day in two weeks of hemodialysis) SECONDARY OUTCOME: 1) Vital signs (blood pressure and heart rate); 2) Clinical laboratory test results INCLUSION CRITERIA: 1) Patient who signed informed consent form to participate in this study. 2) Patient who is 20 years of age or more and under 80 years at first consent with this study. 3) Renal failure patient under hemodialysis or hemodiafiltration stably for three times per week and 3 to 6 hours per session for more than a half year.