Remdesivir: A Review on Analytical Methods for Drug Substances, Pharmaceutical Formulations, and Biological Matrices

Remdesivir (RDV) is a nucleoside analogue prodrug that acts as a viral RNA polymerase inhibitor, triggering chain termination following its incorporation. Approved for the treatment of COVID-19 in 2020, RDV is administered intravenously. This article presents the main physicochemical characteristics of the compound and outlines the most relevant pharmacokinetic and pharmacodynamic aspects. The main analytical methods described in the literature for the detection and quantification of RDV in biological matrices, raw materials, and formulations are presented herein, as well as those for the analysis of degradation products and synthesis impurities. Discussion includes the advantages and disadvantages of these methods, alongside their limits of detection and quantification. Chromatographic methods using a C18 stationary phase, gradient elution with a mobile phase containing up to 100% acetonitrile, and mass spectrometry detection with electron spray ionization in positive mode represent the main choice for RDV determination in biological matrices. While for raw material and formulation analysis, detection is conducted mainly by employing UV in the 237-254 nm range. Impurity detection primarily utilizes C18 columns, isocratic elution with a mobile phase containing up to 70% acetonitrile, and UV detection (237-247 nm). The literature reports fifteen impurities, requiring further RDV stability studies for identifying and quantifying impurities, as well as the development of chiral methods and pharmacopeia standardization.