Adipiplon to be developed in two new indications – anxiety and schizophrenia

Anxiety disorders are commonly treated with the benzodiazepine class of drugs, including drugs such as Valium™, and the Selective Serotonin Reuptake Inhibitors (SSRI’s), such as Paxil™.  While the benzodiazepines typically demonstrate a strong anxiety relieving effect, this class of drugs suffers from a high rate of behavior impairing effects, such as sedation and ataxia (loss of muscle coordination). Side effects commonly associated with the SSRI’s include sexual dysfunction and somnolence.  Approximately 40 million adults in the U.S. suffer from anxiety disorders according to the National Institute for Mental Health. 

In recent primate studies with a compound from its GABA alpha 3 selective partial agonist program, we have demonstrated efficacy equivalent to that of the benzodiazepine class of drugs but with a much wider therapeutic window between anxiety relieving doses and behavior impairing effects typically seen with the benzodiazepines. We believe that at doses lower than those previously explored for insomnia, adipiplon may be a useful therapeutic agent for patients suffering from anxiety while improving on the side-effect profile of currently available drugs such as the benzodiazapines and the SSRI’s. Neurogen plans to commence an exploratory proof-of-concept clinical study in anxiety with adipiplon mid-2008.

We also believe that the wide therapeutic window observed in primates between beneficial effects and impairing effects also opens an opportunity in schizophrenia, where evidence has been growing that links the GABA system to the treatment of cognitive deficits in schizophrenic patients.  We plan to commence an exploratory proof-of-concept clinical study in schizophrenia patients in mid-2008.