Ion channels are transmembrane pores that allow the passage of ions (charged molecules) into or out of a cell. There are hundreds of different ion channels, distinguished by ion selectivity, opening mechanism, and protein sequence. Ion channels can be opened by chemical ligands, voltage fluctuations, acidity changes, temperature variations, or mechanical stimuli (e.g. touch or sound).

Initially, Actelion established an in-house in-vitro electrophysiology group to provide internal support for early preclinical evaluation of drug safety in the area of cardiac electrophysiology. Since the scientific knowledge and technical capabilities required in this area are very similar to those in the area of cardiovascular ion channel therapies, research programs were soon initiated looking for modulators of selected ion channels to treat cardiovascular diseases.

Expansion of the electrophysiology group and integration of new expertise and technologies led to the initiation of research projects targeting ion channels to treat neurological and immunological diseases.