This is a list of investigational insomnia drugs, or drugs that are currently under development for clinical use for the treatment of insomnia but are not yet approved. They may also be referred to as investigational hypnotics.
Chemical/generic names are listed first, with developmental code names, synonyms, and brand names in parentheses. The format of list items is "Name (Synonyms) – Mechanism of Action [Reference]".
This list was last comprehensively updated in September 2025. It is likely to become outdated with time.
Benzodiazepines
Nonbenzodiazepines/Z-drugs
CEE-03-310 is a selective dopamine D1-like receptor antagonist with no appreciable binding affinity for other receptors. Although originally developed by Novo Nordisk A/S as NNC-687 for the treatment of schizophrenia, the company changed its therapeutic focus in the mid-1990s and the full rights to CEE-03-310 and several related compounds were subsequently granted to CeNeS Pharmaceuticals in 1999. CeNeS is currently investigating the drug's potential in the treatment of insomnia and alcohol dependency [340965], [382293], [401496],[416026]. A phase II, double-blind, placebo-controlled trial of CEE-03-310 demonstrated a dose-dependent enhancement of NREM sleep at the beginning of the night without any effects on the quantity of REM sleep [410739].
Moreover, clonidine helps in the treatment of neuroleptic-induced akathisia, stimulant-induced insomnia and clozapine-induced sialorrhea. Moreover, clonidine seems to be an attractive option targeting insomnia in ADHD [10] and remain a good remedy for paediatric insomnia in general [10] , and a case series has also reported that clonidine seems to be beneficial and fairly well tolerated in intractable sleep disorders in children and young adults with neurodevelopmental disorders [11] .