A Novel RP-HPLC Method for Simultaneous Estimation of Vilanterol Trifenatate, Umeclidinium Bromide and Fluticasone Furoate in Inhalation Dry Powder Formulation.

The dry powder inhalation formulation containing vilanterol trifenatate, umeclidinium bromide and fluticasone furoate intended for the therapy of bronchospasm related to chronic obstructive pulmonary disease and bronchial asthma was selected for the development and validation of a novel, selective, accurate, precise, quick and cost-efficient reversed-phase, high-performance liquid chromatography method. Neither an official monograph nor a single method has yet been published for the simultaneous estimation of these three compounds, which makes this method novel. The stationary phase of an ACE-C18-PFP column (250 mm × 4.6 mm, 5 μ) was used with a mobile phase of 25-mM sodium perchlorate buffer (pH 2.5 adjusted with ortho-phosphoric acid) and acetonitrile (40:60% v/v) at a flow rate of 1 mL/min to optimize chromatographic variables. The column temperature was kept at 40°C, and detection was at 224 nm, which was the isosbestic point of these three drugs. Well-resolved good peak symmetry was obtained for all three molecules by isocratic elution in less than 10 min, and the retention times of vilanterol trifenatate, umeclidinium bromide and fluticasone furoate were found to be 3.7, 5.4 and 8.3 min, respectively. The proposed method was validated as per ICH Q2 (R1) guidelines, and the calibration curves were linear in concentration ranges of 5-35 μg/mL for vilanterol trifenatate, 5-80 μg/mL for umeclidinium bromide and 5-150 μg/mL for fluticasone furoate, with mean % recoveries of 99-100%. The limits of detection and quantitation are 0.15 and 0.45 μg/mL for vilanterol trifenatate, 0.58 and 1.77 μg/mL for umeclidinium bromide and 0.32 and 0.96 μg/mL for fluticasone furoate, respectively. Hence, the proposed RP-HPLC technique was successfully used to quantify the inhalation formulation containing all three compounds.