Development and Validation of a Reverse Phase High-Performance Liquid Chromatographic Method for Quantitative Estimation of Etifoxine Hydrochloride in Capsule Dosage Form

Abstract

Etifoxine Hydrochloride (ETH) is a non-benzodiazepine anxiolytic agent widely used for the management of anxiety disorders. The drug exhibits a unique dual mechanism of action involving positive allosteric modulation of GABAA receptors and stimulation of neurosteroid synthesis, resulting in effective anxiolytic activity with fewer sedative adverse effects compared to conventional benzodiazepines. Despite its increasing therapeutic use, limited analytical methods have been reported for the quantitative estimation of Etifoxine Hydrochloride in pharmaceutical dosage forms. The present study aimed to develop and validate a simple, rapid, accurate, precise, and robust reverse-phase high-performance liquid chromatographic (RP-HPLC) method for the quantitative estimation of Etifoxine Hydrochloride in capsule dosage forms. Methods: Chromatographic separation was achieved using a Thermo Hypersil Gold C18 column (4.6 × 250 mm) with a mobile phase consisting of water adjusted to pH 3.2 with 0.1% orthophosphoric acid and acetonitrile (60:40, v/v) under isocratic conditions. The flow rate was maintained at 1.0 mL/min, and detection was performed at 260 nm using a PDA detector. The developed method was validated according to ICH Q2(R1) guidelines for system suitability, linearity, accuracy, precision, ruggedness, robustness, and specificity. Etifoxine Hydrochloride exhibited a well-resolved chromatographic peak with a retention time of approximately 4.9 min. The method demonstrated excellent linearity over the selected concentration range with a correlation coefficient (R²) of 0.999. Accuracy studies showed recoveries ranging from 99.70% to 99.87%, while precision studies yielded %RSD values below 2%. The assay of the marketed capsule formulation showed a drug content of 99.60% of the labeled claim. Robustness and ruggedness studies confirmed the reliability and reproducibility of the method. The developed RP-HPLC method was found to be simple, precise, accurate, specific, and economical. The method is suitable for routine quality control analysis and estimation of Etifoxine Hydrochloride in pharmaceutical capsule formulations.