Therapeutic Equivalence of OsvaRen® Tablets and OsvaRen® Granules

Inclusion Criteria: * Signed written informed consent form is obtained prior to starting the screening visit * Male and female patients 18-80 years of age with dialysis dependent renal failure (CKD 5D) * Patients have been on 3x/week in-centre renal replacement therapy for at least 2 months on either low-flux or high-flux HD or OL- /HDF * Prescribed haemodialysis session duration is ≥ 4 hours * spKt/V ≥ 1.20 according to last in-centre measurement prior the study enrolment * Patients have been on OsvaRen® tablets for at least 12 weeks as sole phosphate binder and the titration phase has been completed according to physician´s discretion * Patients are able to take the study medication as prescribed particularly OsvaRen® stickpacks * Patients are willing to stop any calcium, magnesium or vitamin D containing supplements * Patients are willing to maintain their typical diet with regards to phosphate uptake for the time of the study * Patients are willing to comply with the study protocol Exclusion criteria * Pregnant women (by blood ß-hCG pregnancy test) or women breast-feeding or unwilling to use contraceptive measures during the entire course of the study or * Patients with a life expectancy shorter than the planned duration of the study or * Patients with any acute or chronic severe disease potentially interfering with study outcomes or * Patients with PTH levels \> 800 ng/l or * Patients who participated in an interventional clinical study during the preceding 30 days or * Patients suffering from any other, not mentioned condition which could interfere with the patient's ability to comply with the study or * Patients who previously participated in the same study are excluded from the study