Zaleplon placebo-controlled studies

The pharmacokinetics and pharmacodynamics of zaleplon (10 or 20 mg) and zolpidem (10 or 20 mg) have been investigated in a randomized, double-blind, crossover, placebo-controlled study in 10 healthy volunteers with no history of sleep disorder (15). The half-life of zaleplon was significantly shorter than that of zolpidem. Zaleplon produced less sedation than zolpidem at the two doses studied, and the sedation scores in the zaleplon groups returned to baseline sooner than in the zolpidem groups. Zaleplon had no effect on recent or remote recall, whereas zolpidem had a significant effect on both measures. 

The results of a 1-year open extension of two randomized, double-blind studies of zaleplon have been reported (9). In 316 older patients who took zaleplon nightly from 6 to 12 months and were then followed through a 7-day singleblind, placebo-controlled, run-out period, the safety profile was similar to that observed in a short-term trial in an equivalent population. The data also suggested that therapy for up to 12 months produced and maintained statistically significant improvement in time to persistent sleep onset, duration of sleep, and the number of nocturnal wakenings. Withdrawal was not associated with rebound insomnia. The authors concluded that placebo-controlled, double-blind trials are needed to confirm these results. 

Zaleplon and triazolam have been compared in two concurrent multicenter, randomized, double-blind, placebo-controlled crossover studies in chronic insomniacs (12). Study 1 compared zaleplon (10 and 40 mg) with triazolam (0.25 mg) and placebo study 2 compared zaleplon (20 and 60 mg) with triazolam (0.25 mg) and placebo. All doses of zaleplon produced significant reductions in... 

Zaleplon and zolpidem have been compared in two concurrent multicenter, randomized, double-blind, placebo-controlled crossover studies in chronic insomniacs (12). In study 1, zaleplon 10 mg, zolpidem 10 mg, or placebo were given double-bhnd to 36 healthy subjects under standardized conditions in a six-period, incomplete-block, crossover study (13). The subjects were gently awakened and given the medication at predetermined times, 5, 4, 3, or 2 hours before morning awakening, which occurred 8 hours after bedtime. When they awoke in the morning, subjective and objective assessments of residual effects of hypnotics were administered. There were no serious adverse experiences during the study all adverse events were mild to moderate. The most commonly reported adverse events associated with zaleplon were weakness and somnolence. Weakness, depersonalization, dizziness, and somnolence were the most frequent nervous system adverse events associated with zolpidem. 

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