Semisolid Matrix-Filled Hard Gelatin Capsules of Candesartan Cilexetil

Candesartan cilexetil, an anti-hypertensive drug belonging to BCS Class II, exhibits low solubility and bioavailability.The present study was to develop semisolid matrix-filled hard gelatin capsules containing candesartan cilexetil to enable controlled release, improve bioavailability, and reduce the lag time of drug release.Solid dispersions of the drug were prepared using PEG6000 and PEG4000 as carriers and converted to semisolid matrix using Gelucire50/13, and Labrafil M 2130 CS as carriers.The drug exhibited the highest solubility in the carriers PEG6000 and PEG4000 and hence were selected as carriers for the formulation of solid dispersions.Solid dispersion was prepared using the fusion and solvent evaporation method.The formulation F3, prepared by the fusion method, demonstrated a higher drug release of 91.24 0.74% within 75 minutes.Hence, it was chosen to prepare a semisolid matrix, using Gelucire50/13 or Labrafil M 2130 CS.The semisolid matrix prepared using Labrafil M 2130 CS released 98.20.75% in 10 minutes whereas the marketed formulation released 63.840.69%at the end of 90 mins.The solid dispersions and semisolid matrix were characterized using SEM and XRD.The SEM revealed that the drug was uniformly embedded in the solid dispersion and semisolid matrix.The XRD results showed that the intensity of the peaks decreased in the solid dispersions and semisolid matrix, indicating the conversion of the drug from crystalline to amorphous form which explains the improvement in dissolution rate.