Evaluation of the Genotoxic Impurities of Selpercatinib Through HPLC and LCMS/MS Identification of Selpercatinib Stress Degradation Products

Abstract

The current investigation entails the characterization of seven degradation products (DPs) formed in different stress conditions of selpercatinib employing liquid chromatography–tandem mass spectrometry (LCMS/MS). Additionally, high-performance liquid chromatographic (HPLC) method for precise quantifying genotoxic impurities of selpercatinib. To explore the stability profile of selpercatinib, it was subjected to forced degradation experiments including acidic, basic, oxidative, photolytic, and thermal stress were conducted. These experiments revealed the degradation of selpercatinib under basic, acidic and photolytic conditions, resulting in the formation of seven distinct DPs. The chromatographic resolution of selpercatinib and its impurities along with DPs was effectively attained on Zorbax C18 (250 mm × 4.6 mm, 5 μm) column using aqueous ammonium acetate and methanol in 70:30 (v/v) at pH 4.5 with 0.1% formic acid as mobile phase, pumped isocratically at 0.9 mL/min and 226 nm wavelength. The approach generates a precise calibration curve that accurately fits within 15-120 μg/mL range for selpercatinib and LOQ (0.015 μg/mL) to 0.12 μg/mL for impurities with acceptable precision, accuracy and recovery. The efficacy of this method was validated through LCMS/MS, which allowed for the verification of the chemical structures of newly generated degradation products of selpercatinib. Hence this approach can appropriate for resolution and quantification of genotoxic impurities of selpercatinib and can also applicable for evaluation stress degradation products.