To evaluate efficacy and safety of 3.5-mg zolpidem tartrate sublingual tablets (ZST) on latency to sleep onset after middle-of-the-night (MOTN) awakenings in patients with insomnia characterized by difficulty returning to sleep after MOTN awakenings.
Multicenter randomized, double-blind, placebo-controlled, parallel-group.
There were 295 adults (median age 43 y; 68.1% female) with primary insomnia and difficulty returning to sleep after MOTN awakenings (three or more MOTN awakenings/wk during screening).
After a 2-wk, single-blind placebo eligibility period, participants were randomized 1:1 to as-needed MOTN dosing with 3.5 mg ZST or placebo for 28 nights. An interactive voice response system determined if the study drug could be taken and recorded sleep/wake efficacy measures.
ZST significantly (P < 0.0001) decreased latency to sleep onset over 4 wk (baseline 68.1 min; ZST 38.2 min) compared with placebo (baseline 69.4 min; placebo 56.4 min). Ratings of morning sleepiness/alertness significantly (P = 0.0041) favored the ZST group on nights medication was taken but not on other nights. Participants in the ZST group took the study drug on 62% of nights during the 4 wk; members of the placebo group took study medication on 64% of nights. Adverse events were generally mild and at the same rate (19.3% of participants) in both groups. There were no treatment-related serious adverse events (SAEs), and one adverse event-related study discontinuation from the placebo group. Dosing/week did not increase across the study.
3.5 mg ZST used as needed significantly reduced latency to return to sleep in comparison with placebo in these patients with insomnia. Sleep quality was improved, and morning sleepiness/alertness scores also improved. ZST was well tolerated. These data demonstrate the utility of a sleep-promoting agent when used as needed in the MOTN.
Roth T; Krystal A; Steinberg FJ; Singh NN; Moline M. Novel sublingual low-dose zolpidem tablet reduces latency to sleep onset following spontaneous middle-of-the-night awakening in insomnia in a randomized, double-blind, placebo-controlled, outpatient study. SLEEP 2013;36(2):189-196.