Pharmacokinetics of zolpidem from sublingual zolpidem tartrate tablets in healthy elderly versus non-elderly subjects.

BACKGROUND: Pharmacokinetic parameters of sedative-hypnotic medications can be influenced by age and gender. OBJECTIVE: This study analyzed pharmacokinetic parameters of zolpidem, formulated as a sublingual zolpidem tartrate tablet (ZST; Intermezzo®), in healthy elderly males and females (mean age 72 years) and in non-elderly males and females (34 years). METHODS: This was a randomized, single-dose, open-label, two-way crossover study evaluating pharmacokinetic parameters of 1.75 and 3.5 mg dosages of ZST in elderly subjects (n = 22), and 3.5 mg dosages of ZST in non-elderly subjects (n = 24). Main outcome measures were pharmacokinetic parameters, including area under the plasma concentration-time curve (AUC), maximum observed concentration (C(max)), time to reach C(max) (T(max)), elimination half-life (T(½)), and apparent oral clearance (CL/F). RESULTS: Dose proportionality in zolpidem exposure was maintained between 1.75 and 3.5 mg doses for both elderly females and males. With administration of the 3.5 mg dose of ZST to elderly and non-elderly subjects, significantly higher systemic exposure was seen in elderly females (C(max) +44.6 %, P < 0.01; AUC +40.4 %) compared with non-elderly females. However, systemic exposure was only modestly higher in elderly males compared with non-elderly males. Greater exposure was seen in elderly females compared to males (C(max) +46.8 %, P < 0.01; AUC +31.4 %). In this study, exposure between non-elderly females and males was equivalent. Changes in T(½) and T(max) values were not observed, with no significant age effect on oral clearance. There were no apparent differences in tolerability among age and gender groups. CONCLUSION: Elderly individuals were found to have higher C(max) and AUC values compared with non-elderly subjects. C(max) and AUC were greater in elderly women compared with elderly men.

Gender influences on efficacy and safety of sublingual zolpidem tartrate for middle-of-the-night awakening in insomnia.

OBJECTIVE: Evaluate potential gender effects on efficacy and safety of a buffered zolpidem sublingual tablet (ZST) formulation. METHODS: Post hoc analysis of the pivotal sleep laboratory and outpatient studies, per gender. RESULTS: In the sleep laboratory study, polysomnography-derived latency to persistent sleep after middle-of-the-night was significantly improved for both genders at both 1.75 mg and 3.5 mg ZST (females: 15.7 and 8.6 min, respectively, vs. 27.7 min [placebo]; males: 19.0 and 12.7 min vs. 29.0 min [placebo]) with no significant gender differences. In the outpatient study, subjective sleep onset latency after middle-of-the-night was significantly shorter for both genders treated with ZST 3.5 mg versus placebo over the 4-week average (females: 37.3 vs. 59.4 min, p < 0.0001; males: 38.6 vs. 55.1 min, p ≤ 0.01). There were no gender differences in subjective sleep onset latency after middle-of-the-night awakening. In the outpatient study, weekly usage of ZST and placebo by both genders declined throughout the study. Morning alertness following dosing nights improved in both genders, although significant only in females. In both studies, there were no gender differences in adverse events. CONCLUSION(S): Time to return to sleep after middle-of-the-night dosing with ZST improved in both genders, with no gender differences in efficacy and safety.

Gender differences in pharmacokinetics and pharmacodynamics of zolpidem following sublingual administration.

The effect of dose and gender on the pharmacokinetics (PK) and pharmacodynamics (PD) of zolpidem after administration of a buffered zolpidem sublingual tablet (ZST; Intermezzo®, Purdue Pharma L.P., Stamford, CT, USA) was evaluated in healthy non-elderly male and female volunteers. Subjects received a single morning dose of ZST (1.0, 1.75, and 3.5 mg) or placebo in a four-way crossover study. In male and female subjects zolpidem PK were linear, with area under the curve (AUC) proportional to dose, and apparent oral clearance and elimination half-life independent of dose. However, AUC averaged 40% to 50% higher in females than in males receiving the same dose. The gender effect was incompletely explained by body weight. In females, ZST produced PD changes consistent with benzodiazepine agonist effects, particularly at the 3.5-mg dose. For several PD variables, PD effects were significantly related to plasma zolpidem concentrations when data were aggregated across subjects. However, there was variability in response among individuals. In males, PD effects of zolpidem seldom differed from placebo regardless of plasma concentration. The findings confirm that zolpidem clearance is lower in females than in males. PD effects of zolpidem from ZST are greater in female subjects, due to a combination of higher plasma concentrations and greater intrinsic sensitivity.

Influence of food on pharmacokinetics of zolpidem from fast dissolving sublingual zolpidem tartrate tablets.

Ingesting food can impact the pharmacokinetics of sedative-hypnotic drugs. A buffered zolpidem sublingual tablet (ZST) recently became available for the treatment of middle-of-the-night awakening. In this randomized, open-label, single-site study, the pharmacokinetic profile of ZST was evaluated when administered while fasting and following a standard high-fat meal (fed state). Healthy adults aged 18-64 years received a single morning dose of 3.5 mg ZST in the fed or fasting state. From 20 min to 3 h post-dose, zolpidem plasma levels were lower in the fed state compared to the fasting state. After 4 h post-dose (corresponding to "morning wake time"), higher zolpidem plasma levels were evident in the fed state. Area under the concentration-time curve (AUC) values for the 0-8 h interval were 160 ng/mL h in the fed state and 203 ng/mL h in the fasting state (P < .001). In the fed versus fasting states, Cmax was 32.0 ng/mL versus 57.3 ng/mL (P < .001), respectively, and Tmax was 3.0 h versus 0.92 h (P < .001), respectively. Together these data suggest that administration of ZST in the fed state is not optimal for maximizing the likelihood of therapeutic benefit and minimizing the probability of residual sedation.

Comparison of pharmacokinetic profiles of zolpidem buffered sublingual tablet and zolpidem oral immediate-release tablet: results from a single-center, single-dose, randomized, open-label crossover study in healthy adults.

BACKGROUND: A zolpidem sublingual tablet (ZST) formulation was recently approved by the US Food and Drug Administration to treat middle-of-the-night (MOTN) awakening with difficulty returning to sleep. OBJECTIVE: The aim of this study was to compare the zolpidem pharmacokinetic profiles of 3.5-mg ZST and 10-mg immediate-release (IR) oral zolpidem in healthy female and male adults. METHODS: This randomized, open-label crossover study compared the pharmacokinetic profile of ZST with that of IR oral zolpidem in healthy adults. RESULTS: The study enrolled 19 males and 14 females. After 3.5-mg ZST and 10-mg IR, respectively, mean zolpidem plasma concentrations at 15 minutes (22 vs 17 ng/mL, respectively, in females and 18 vs 10 ng/mL in males) and AUCs from zero to 15 minutes (2.3 vs 0.8 ng · h/mL in females and 1.6 vs 0.5 ng · h/mL in males) were substantially greater for ZST, despite the larger absolute IR dose. After 3.5-mg ZST and 10-mg IR, respectively, clearance was lower in females, even after correcting for body weight (2.63 vs 2.88 mL/min/kg in females and 3.63 vs 3.91 mL/min/kg in males). The lag time prior to the start of first-order absorption was notably shorter for ZST than IR in both males (8 vs 21 minutes) and females (5 vs 22 minutes). Both zolpidem formulations were generally well tolerated by both genders. CONCLUSIONS: Systemic exposure of zolpidem was higher in females for both formulations. Plasma levels and AUC were higher, and clearance was lower, in females with both zolpidem formulations. The initial rate of absorption was faster, and initial systemic exposure was greater, with ZST compared with oral IR.

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.

STUDY OBJECTIVES: 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. DESIGN: Multicenter randomized, double-blind, placebo-controlled, parallel-group. SETTING: Outpatient. PATIENTS: 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). INTERVENTIONS: 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. RESULTS: 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. CONCLUSIONS: 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. CLINICAL TRIALS REGISTRATION: NCT00466193: "A Study of Zolpidem Tartrate Tablet in Adult Patients with Insomnia" http://www.clinicaltrials.gov/ct2/show/NCT00466193?spons=%22Transcept+Pharmaceuticals%22&spons_ex=Y&rank=2

Daytime pharmacodynamic and pharmacokinetic evaluation of low-dose sublingual transmucosal zolpidem hemitartrate.

OBJECTIVES: Buffered low-dose sublingual transmucosal zolpidem lozenge hemitartrate (ST zolpidem) is being developed for the treatment of middle-of-the-night insomnia. The objective of this double-blind placebo-controlled cross-over study (n = 24) was to evaluate the pharmacokinetics (PK) and daytime-sedative profile of 1.0, 1.75, and 3.5 mg dose of the formulation. METHODS: Daytime sedation was measured pre-dose and up to 5 h post-dose objectively by the Digit Symbol Substitution Test (DSST) and subjectively using the Visual Analog Scale (VAS). Blood samples for PK assessment was collected pre-dose and up to 12 h post-dose. RESULTS: The 1.75 and 3.5 mg, but not the 1 mg, ST zolpidem produced significant sedation versus placebo within 20 min of dosing which lasted for up to 3 h. Zolpidem from the formulation was rapidly absorbed and reached maximum plasma concentrations within 38 min of dosing, however the half-life was independent of the dose and side effects were consistent with the known pharmacology of the drug. CONCLUSIONS: ST zolpidem produced rapid, short duration of sedation and the effect was consistent with its PK profile. This novel low-dose formulation of zolpidem may provide clinicians and patients with a prn option for the management of sleep maintenance insomnia.