The aim of the paper was to formulate a combined oral dosage form of rosuvastatin calcium and amlodipine besylate and to develop and validate an analytical method to be adopted for both routine quality control assay and in vitro dissolution studies of the formulation. The proposed combination formulation has shown compatibility with the chosen excipients, verified through FT-IR study. A novel gradient RP-HPLC method was developed and validated according to the ICH guideline which was found to be suitable for the simultaneous estimation of rosuvastatin calcium and amlodipine besylate from the formulation. The retention time of 2.7 and 6.08 min allows the analysis of large amount of samples with less mobile phase which makes the method economic. The dissolution profiles of both the drugs in different dissolution medium were encouraging which makes the combination formulation of rosuvastatin calcium and amlodipine besylate superior and effective in achieving patient compliance.
Keywords: % RSD, percentage relative standard deviation; Amlodipine besylate; BP, British Pharmacopeia; CVD, cardiovascular disease; Ca2+, calcium; Combination formulation; Compatible; FDA, Food and Drug Administration; FT-IR, Fourier Transform Infrared spectroscopy; HMG-CoA, 3-hydroxy-3-methylglutaryl coenzyme-A; ICH, International Conference on Harmonization; IR, infrared; LC, liquid chromatography; LOD, limit of detection; LOQ, limit of quantitation; Method validation; PDA, photo diode array; RP-HPLC, reverse phase high performance liquid chromatography; Rosuvastatin calcium; THF, tetrahydrofuran; USP, United States Pharmacopeia; ml, milliliter; μg, microgram; μl, microliter.