Indiplon in the management of insomnia

Indiplon is a novel pyrazolopyrimidine, nonbenzodiazepine γ-aminobutyric acid (GABA) agonist studied for the treatment of insomnia. This article reviews the chemistry, pharmacology, clinical pharmacokinetics, drug interactions, clinical trials, safety, tolerability, contraindications, use in special populations, and dosing of indiplon. OVID, International Pharmaceutical Abstracts (IPA), and PubMed databases were searched (1966 to February 2009) for the keywords indiplon, NBI-34060, and insomnia. References of key articles were also reviewed to identify additional publications. Only English language articles were selected for review. Indiplon has been shown to have high affinity and selectivity for the GABAα(1) receptor subunit associated with sedation. In clinical studies, indiplon has demonstrated efficacy in improving latency to sleep onset, latency to persistent sleep, total sleep time, wake time after sleep onset, number of awakenings after sleep onset, and overall sleep quality when compared to placebo. Indiplon has a favorable safety profile with limited rebound insomnia and no tolerance. Neurocrine Biosciences, Incorporated received an Approvable Letter from the United States Food and Drug Administration in December 2007 for the indiplon IR 5 mg and 10 mg capsules based on meeting three additional requirements. At the time of this writing, indiplon remains unapproved.