GRX-917 is a proprietary (patent-protected until 2036), improved version of Etifoxine, an anxiety drug first approved in France 39 years ago. GRX-917 is a deuterated version of Etifoxine (specific hydrogen atoms were replaced by isotopic deuterium (heavy hydrogen) atoms). Like the vast majority of deuterated drug analogs, GRX-917 retains the same mechanism of action and pharmacological properties as etifoxine, because their biological properties are identical.

Clinically, GRX-917’s speed of onset, efficacy and side effects profile will be identical to the original drug. However, the pharmacokinetic profile is significantly improved as a result of reduced metabolism due to deuterium stabilization.  Critically, GRX-917’s metabolism remains identical to etifoxine, but with a reduced rate. This is expected to lead to lower and/or less frequent dosing and more consistent exposure, leading to better efficacy and less potential side effects/adverse effects than the original drug.