Chiral HPLC Method Development and Validation for Content Of S-Isomer in Fezolinetant on Cellulose Based Stationary Phase

Abstract

Fezolinetant (RFZL) is a small molecule, selective neurokinin-3 (NK3) receptor antagonist recommended for the management of menopausal vasomotor symptoms (hot flashes). In the proposed research work, a normal-phase HPLC method was developed for content of  Fezolinetant (S) isomer (SFZL) in Fezolinetant (R) isomer (RFZL) and validated in accordance with ICH Q2(R1) guidelines. Satisfactory resolution of the enantiomer was achieved using a Chiralpak IB chiral stationary phase. The mobile phase consisted of a 70:30 (v/v) mixture of n-hexane and ethanol 70:30 (v/v), operated in isocratic mode at a flow rate of 1.0 mL/min. The column temperature was maintained at 45°C, and the total analysis run time was 15 minutes. The developed method was fully validated and demonstrated to be suitable for the quantitative determination of the Fezolinetant (S) isomer (SFZL) in Fezolinetant (R) isomer (RFZL). Linearity for Fezolinetant (S) isomer (SFZL) was plotted with concentration between 0.67 µg/ml to 13.3 µg/ml. Limit of quantification and limit of detection of Fezolinetant (S) isomer (SFZL) were determined 0.67 µg/ml and 0.22 µg/ml respectively and average recovery of Fezolinetant (S) isomer (SFZL) in Fezolinetant (R) isomer (RFZL) was 100% ± 4%. Newly developed normal phase HPLC method was successfully adopted to control Fezolinetant (S) isomer (SFZL) in Fezolinetant (R) isomer (RFZL). by HPLC.