Characterization and in silico Mutagenic Assessment of a New Betahistine Degradation Impurity

Currently, the pharmaceutical industry devotes great attention to drug degradation products because these compounds can offer risks to patients. A previous degradation study of betahistine (N-α-methyl-2-pyridylethylamine) conducted under different stress conditions detected three main impurities named A, B and C. Degradation products were analyzed by high-resolution mass spectrometry in electrospray source and time of flight analyzer (ESI-TOF) and nuclear magnetic resonance (NMR). Impurity mutagenicity was evaluated by Derek Nexus and Sarah Nexus softwares. Liquid chromatography hyphenate with tandem mass spectrometry (LC-MS/MS) analysis of the betahistine forced degradation sample indicated the presence of a new impurity, which was named impurity C1. 2D NMR experiments allowed the complete structural characterization of the new entity. The active pharmaceutical ingredient and degradation impurities were classified as inactive in the in silico mutagenic studies. Systematic investigation of a forced degradation sample led to the characterization of a new betahistine impurity. The in silico mutagenicity study of the betahistine degradation impurities may be useful in the risk assessment of the drug products.