Indiplon works by enhancing the action of the inhibitory neurotransmitter GABA, like most other nonbenzodiazepine sedatives.

[4]: 454  In 1998 Lederle licensed it, along with other early stage drug candidates, to DOV Pharmaceutical, a startup formed by former Lederle employees, and Dov exclusively sublicensed its rights in the drug to Neurocrine Biosciences in that same year.

[4] Indiplon was originally scheduled for release in 2007, when Sanofi-Aventis' popular hypnotic zolpidem lost its patent rights in the United States and thus became available as a much less expensive generic.

In 2002, Neurocrine Biosciences had entered into an agreement with Pfizer to co-market indiplon in the US, in a deal worth a potential $400mn.

[10] Following the 2007 FDA letter, Neurocrine decided to discontinue all clinical and marketing development of Indiplon in the United States.