Chiroscience Hopes Verapamil Isomer Could Cut Constipation

Chiroscience has started Phase I trials of the isomers of verapamil, acalcium antagonist, to see if a single-isomer form can offer advantages over the racemate. The company is conducting the research in partnership with BASF subsidiary Knoll AG.

The first Phase I study will compare the effects of the S- and R-isomers of verapamil in 15 healthy volunteers, with the primary aim of seeing whether the drug's constipating effects, which limit its use at high doses, are caused by a particular form. Results are expected in March.

Two other Phase I studies are to start by the end of this month. The first will see if verapamil's efficacy can be improved in an existing indication, and the second will investigate a new use for the drug. There were rumors that the first study would look at improving efficacy in hypertension - a condition which carries the highest recommended daily dose of verapamil's indications (which also include angina and arrhythmia) - but Chiroscience would not confirm this. Likewise, the firm would not reveal the potential new indication for the drug.