Adipiplon is an anxiolytic

Anxiolytic

An anxiolytic is a drug used for the treatment of anxiety, and its related psychological and physical symptoms...

 drug developed by Neurogen Corporation. It has similar effects to benzodiazepine

Benzodiazepine

A benzodiazepine is a psychoactive drug whose core chemical structure is the fusion of a benzene ring and a diazepine ring...

 drugs, but is structurally distinct and so is classed as a nonbenzodiazepine

Nonbenzodiazepine

The nonbenzodiazepines, also called benzodiazepine-like drugs, are a class of psychoactive drugs pharmacologically resembling the benzodiazepines, with similar benefits, side effects and risks, despite having dissimilar or entirely different chemical structures.-Classes:There are currently three...

 anxiolytic.

Adipiplon is a subtype

Protein subunit

In structural biology, a protein subunit or subunit protein is a single protein molecule that assembles with other protein molecules to form a protein complex: a multimeric or oligomeric protein. Many naturally occurring proteins and enzymes are multimeric...

-selective

Binding selectivity

Binding selectivity refers to the differing affinities with which different ligands bind to a substrate forming a complex. A selectivity coefficient is the equilibrium constant for the reaction of displacement by one ligand of another ligand in a complex with the substrate...

 GABA_A receptor partial agonist

Partial agonist

Partial agonists bind and activate a given receptor, but have only partial efficacy at the receptor relative to a full agonist...

, which binds preferentially to the α₃

GABRA3

Gamma-aminobutyric acid receptor subunit alpha-3 is a protein that in humans is encoded by the GABRA3 gene.- Function :GABA is the major inhibitory neurotransmitter in the mammalian brain where it acts at GABAA receptors, which are ligand-gated chloride channels...

 subtype. This is significant as while several previous nonbenzodiazepine drugs have been developed that are selective for α_2/3 over the other subtypes, adipiplon is one of the first drugs selected for clinical development which is able to discriminate between α₂ and α₃, as well as showing little affinity for the α₁ or α₅ subtypes - alpidem

Alpidem

Alpidem is an anxiolytic drug from the imidazopyridine family, related to the more well known sleeping medication zolpidem. Unlike zolpidem however, alpidem does not produce sedative effects at normal doses, and is instead used specifically for the treatment of anxiety.Alipidem was developed by ...

 is selective for α₃ over α₂, but still has moderate affinity for α₁, whereas adipiplon is highly α₃-selective with little affinity for either α₁, α₂ or α₅.

Adipiplon is being researched as a potential medication for the treatment of anxiety

Anxiety

Anxiety is a psychological and physiological state characterized by somatic, emotional, cognitive, and behavioral components. The root meaning of the word anxiety is 'to vex or trouble'; in either presence or absence of psychological stress, anxiety can create feelings of fear, worry, uneasiness,...

 and insomnia

Insomnia

Insomnia is most often defined by an individual's report of sleeping difficulties. While the term is sometimes used in sleep literature to describe a disorder demonstrated by polysomnographic evidence of disturbed sleep, insomnia is often defined as a positive response to either of two questions:...

, and is currently (as of 2008) in Phase IIb trials.