(S)-Etifoxine is a first in class pain-relieving drug candidate, with the power of morphine and oxycodone, but without the addictive, sedative and GI side effects. (S)-etifoxine is an isomer, chemically isolated from Etifoxine (Stresam), an approved racemic drug (off patent) prescribed in Europe. Preclinical studies determined that the (S)-isomer of Stresam® ((S)-etifoxine) is a non-sedating anxiolytic. It was also discovered that (S)-etifoxine possesses highly potent analgesic activity comparable to morphine (the gold standard) which is consistent with Stresam®’s TSPO-mediated effects on chemotherapy-induced neuropathy and peripheral nerve injury. However, (S)-etifoxine does not display any of the negative side-effects associated with morphine. Even more notably, Stresam® has demonstrated peripheral nerve regeneration and functional recovery. It is believed that (S)-etifoxine will retain these same properties.

(R)-Etifoxine is an isomer, chemically isolated from Etifoxine (Stresam), an approved racemic drug (off patent) prescribed in Europe. (R)-Etifoxine was developed by Xytis Inc for treatment pain, mental disease, and central nervous system disorders. However future development has been discontinued.