Chiral LC method development for stereo-selective separation and quantification of Ivosidenib and its S,R and R,R isomeric impurities in drug substance and finished product

A robust and reliable chiral HPLC method was developed and validated for the separation and quantification of ivosidenib and its stereoisomeric impurities (S,R and R,R forms) in pharmaceutical formulations and bulk drug samples. The study optimized various analytical parameters including the mobile phase composition, pH modifiers, flow rate, detector wavelength and column temperature. A mobile phase comprising of methanol and 0.1% formic acid in 65:35 (v/v) ratio, with a flow rate of 0.8 mL/min and a detection wavelength of 248 nm, was identified as optimal. These conditions provided high-resolution symmetrical peaks with retention times of 6.5, 5.7 and 4.8 minutes for ivosidenib, S,R and R,R impurities respectively, ensuring a total analysis time of 10 minutes. System suitability parameters including peak resolution and retention time reproducibility, were within acceptable limits. Linearity studies demonstrated a strong correlation (R² > 0.999) for ivosidenib (25–250 μg/mL) and its impurities (0.25–2.50 μg/mL). Sensitivity analysis revealed detection limits as low as 0.075 μL/mL for the impurities. Accuracy studies across multiple concentrations showed recovery rates within 98–102%, with low relative standard deviations, indicating the method's high precision and reproducibility. Robustness testing confirmed the method's reliability. Stability studies validated that ivosidenib and its isomeric impurities remained stable for at least 15 days under both room temperature (25°C) and refrigeration (2°C) conditions. The results demonstrated compliance with pharmacopoeial standards, with ivosidenib content at 99.15% and impurity levels below the detection limit, confirming the stereoselective efficiency of the formulation. The method’s reliability, simplicity and applicability to both bulk batch and formulation samples make it an essential tool for pharmaceutical quality assurance.