Determination of Olmesartan in Bulk and Pharmaceutical Dosage Forms through the Development and Validation of Stability-indicating RP-HPLC Method

Background: Angiotensin II type 1 (AT 1) receptor antagonist (angiotensin receptor blocker (ARB) called Olmesartan medoxomil (OLM) prevents angiotensin II from acting on the renin-angiotensin-aldosterone pathway, which is a crucial factor in the development of hypertension. OLM is reported to rapidly hydrolyze into its active metabolite, Olmesartan, in plasma after oral treatment. Objective: The objective of the ongoing study was to develop an easy-to-use, precise, and reliable RP-HPLC method for the determination of Olmesartan in bulk as well as pharmaceutical dosage forms. Methods: The stability indicating HPLC method for assay includes the use of Kromasil 100-5-C8 (100 mm × 4.6 mm) column, UV detector 265 nm, and mobile phase composition was a mixture of Acetonitrile: water (70:30) and flow rate of 1.0 mL/min. ICH guidelines were followed in the method's validation. To assess the method's specificity and stability in showing characteristics, stress degradation studies were carried out. The working standard solution of Olmesartan was exposed to 0.1 N HCl at room temperature, 0.1 N NaOH at room temperature, 30 percent hydrogen peroxide by volume, and UV radiation in order to conduct a degradation study. Results: The retention periods of the drug were found to be 1.36 and 1.47 min for standard and sample solutions, respectively. The degradation behaviour of drug under different conditions was studied. The drug was found susceptible to acidic, alkaline and oxidative conditions while it was found stable in photolytic condition. The developed stability-indicating RP-HPLC method for assay was validated as per ICH Q2 guidelines and the validation parameters such as accuracy, precision and specificity were obtained within the accepted criteria. Conclusion: It may be concluded that this method is stability-indicating and specific and can successfully be applied to analyze tablet dosage form containing Olmesartan.