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Updated: Jun 21, 2026

Quantitative Structure-Activity Relationship, Activity Prediction, and Molecular Dynamics of Non-nucleotide Reverse Transcriptase Inhibitors
Published on: May 9, 2025
Structural determinants for histamine H(1) affinity, hERG affinity and QTc prolongation in a series of terfenadine
Robert Aslanian1, John J Piwinski, Xiaohong Zhu
1The Schering Plough Research Institute, 2015 Galloping Hill Rd., Kenilworth, NJ 07033, USA. robert.aslanian@spcorp.com
Abstract:
In the late 1980's reports linking the non-sedating antihistamines terfenadine and astemizole with torsades de pointes, a form of ventricular tachyarrhythmia that can degenerate into ventricular fibrillation and sudden death, appeared in the clinical literature. A substantial body of evidence demonstrates that the arrhythmogenic effect of these cardiotoxic antihistamines, as well as a number of structurally related compounds, results from prolongation of the QT interval due to suppression of specific delayed rectifier ventricular K+ currents via blockade of the hERG-IKr channel. In order to better understand the structural requirements for hERG and H(1) binding for terfenadine, a series of analogs of terfenadine has been prepared and studied in both in vitro and in vivo hERG and H(1) assays.
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