Determination of the binding parameter constants of Renagel capsules and tablets at pH 7 by high performance capillary electrophoresis.

Sevelamer hydrochloride is a cross-linked polymeric amine; it is the active ingredient in Renagel capsules and tablets. Sevelamer hydrochloride is indicated for the control of hyperphosphatemia in patients with end-stage renal disease (ESRD). The binding parameter constants of sevelamer hydrochloride were determined using high performance capillary electrophoresis (HPCE) and the Langmuir approximation for three different dosage forms at pH 7.0. The three dosage forms were Renagel 403 mg capsules, Renagel 400 mg tablets and Renagel 800 mg tablets. The results demonstrate the in vitro bioequivalence of all three dosage forms at pH 7.0. These results are in very good agreement with previously published results obtained by ion chromatography.