Results from Phase II studies demonstrated the effects of gaboxadol on sleep architecture (visual polysomnograph and computerized analysis of the waveform through the stages of sleep) in both primary and transient insomnia.
In a model of transient insomnia the traditional measures of sleep onset and maintenance were also reported. Gaboxadol, an investigational agent under clinical development by Merck and H. Lundbeck A/S for the treatment of insomnia, is a first-in-class selective extrasynaptic GABA(A) receptor agonist (SEGA).
In the clinical studies presented in primary and transient insomnia, electroencephalogram (EEG) analyses showed that gaboxadol caused statistically significant increases in deep sleep, i.e. visually scored slow wave sleep or objectively measured slow wave activity (SWA) as compared to placebo. Slow waves are the characteristic and predominant waveform during sleep stages 3 and 4.