Zolpidem Tartrate Sublingual

1 INDICATIONS AND USAGE Zolpidem tartrate sublingual tablets are indicated for use as needed for the treatment of insomnia when a middle-of-the-night awakening is followed by difficulty returning to sleep. Limitations of Use: Zolpidem tartrate sublingual tablets are not indicated for the treatment of middle-of-the-night insomnia when the patient has fewer than 4 hours of bedtime remaining before the planned time of waking. Zolpidem tartrate sublingual tablets are a GABA A agonist indicated for use as needed for the treatment of insomnia when a middle-of-the-night awakening is followed by difficulty returning to sleep Limitation of Use : Not indicated for the treatment of middle-of-the night awakening when the patient has fewer than 4 hours of bedtime remaining before the planned time of waking

2 DOSAGE AND ADMINISTRATION Take only if 4 hours of bedtime remain before the planned time of waking (2.1, 5.1) Zolpidem tartrate sublingual tablets should be placed under the tongue and allowed to disintegrate completely before swallowing. The tablet should not be swallowed whole. (2.1) The effect of zolpidem tartrate sublingual tablets may be slowed if taken with or immediately after a meal (2.1) Recommended dose is 1.75 mg for women and 3.5 mg for men, taken only once per night if needed (2.2) Lower doses of CNS depressants may be necessary when taken concomitantly with zolpidem tartrate sublingual tablets (2.3) Co-administration with CNS depressants: Recommended dose is 1.75 mg for men and women (2.3) Geriatric patients and patients with hepatic impairment: Recommended dose is 1.75 mg for men and women (2.4, 2.5) 2.1 Important Administration Instructions Zolpidem tartrate sublingual tablets are to be taken in bed when a patient wakes in the middle of the night and has difficulty returning to sleep. Zolpidem Tartrate Sublingual Tablets should only be taken if the patient has at least 4 hours of bedtime remaining before the planned time of waking [see Warnings and Precautions (5.1)]. Zolpidem tartrate sublingual tablets should be placed under the tongue and allowed to disintegrate completely before swallowing. The tablet should not be swallowed whole. For optimal effect, zolpidem tartrate sublingual tablets should not be administered with or immediately after a meal. The tablet should be removed from the pouch just prior to dosing. 2.2 Basic Dosing Information The recommended and maximum dose of zolpidem tartrate sublingual tablets are 1.75 mg for women and 3.5 mg for men, taken only once per night as needed if a middle-of-the-night awakening is followed by difficulty returning to sleep. The recommended doses for women and men are different because women clear zolpidem from the body at a lower rate than men [see Use in Specific Populations (8.6)] . 2.3 Use with CNS Depressants The recommended zolpidem tartrate sublingual tablets dose for men and women who are taking concomitant CNS depressants is 1.75 mg. Dose adjustment of concomitant CNS depressants may be necessary when co-administered with zolpidem tartrate sublingual tablets because of potentially additive effects. The use of zolpidem tartrate sublingual tablets with other sedative-hypnotics (including other zolpidem products) at bedtime or the middle of the night is not recommended [see Warnings and Precautions (5.1)]. 2.4 Use in Geriatric Patients Geriatric patients may be especially sensitive to the effects of zolpidem. The recommended dose of zolpidem tartrate sublingual tablets in men and women over 65 years old is 1.75 mg, taken only once per night if needed [see Use in Specific Populations (8.5)]. 2.5 Use in Patients with Hepatic Impairment The recommended dose of zolpidem tartrate sublingual tablets in patients with hepatic impairment is 1.75 mg, taken only once per night if needed [see Clinical Pharmacology (12.3)].

6 ADVERSE REACTIONS The following serious adverse reactions in zolpidem-treated patients are discussed in greater detail in other sections of the labeling: Complex Sleep Behaviors [See Warnings and Precautions (5.1)] CNS-Depressant Effects and Next-Day Impairment [See Warnings and Precautions (5.2)] Serious Anaphylactic and Anaphylactoid Reactions [See Warnings and Precautions (5.2)] Abnormal Thinking and Behavioral Changes [See Warnings and Precautions (5.5)] Withdrawal Effects [See Warnings and Precautions (5.8)] Most commonly observed adverse reactions (> 1% in adult patients) are headache, nausea, and fatigue. (6.1) To report SUSPECTED ADVERSE REACTIONS, contact Endo at 1-800-828-9393 or FDA at 1-800-FDA-1088 or http://w ww.fda.gov/medwatch . 6.1 Clinical Trials Experience The safety data described below are based on two double-blind placebo-controlled trials of zolpidem tartrate in adult patients with insomnia characterized by difficulty returning to sleep after a middle-of-the-night awakening [see Clinical Studies (14.1)]. These two trials included 230 and 82 patients treated with 3.5 mg and 1.75 mg of zolpidem tartrate, respectively. The first study was a 3-way crossover sleep-laboratory study in 82 patients (58 female and 24 male; median age 47 years; 51% Caucasian, 44% African-American) of 1.75 mg and 3.5 mg of zolpidem tartrate compared to placebo (Study 1). The second study was a 4-week, parallel-group at-home study in 295 patients (201 female and 94 male; median age 43 years) of 3.5 mg of zolpidem tartrate compared to placebo, used on an as-needed basis after spontaneous middle-of-the-night awakenings (Study 2). In Study 2, patients took zolpidem tartrate during the night on 62% of study nights. Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in actual practice. Table 1 shows the incidence of adverse reactions reported in Study 2 that occurred in 2% or more of zolpidem tartrate-treated (3.5 mg) patients in which the incidence was greater than the incidence in placebo-treated patients. For women and other patients taking the 1.75 mg dose in Study 1, the incidence of adverse reactions was similar to the incidence seen with 3.5 mg of zolpidem tartrate in Table 1. The most commonly reported adverse reactions in all treatment groups were headache, nausea, and fatigue. Table 1: Summary of Adverse Reactions (≥ 2%) in Outpatient, Double-Blind, Parallel-Group, Placebo-Controlled Study (Study 2) MedDRA System Organ Class Preferred Term 3.5 mg zolpidem tartrate (n=150) Placebo (n=145) Gastrointestinal Disorders 4% 2% Nausea 1% 1% General Disorders and Administration Site Conditions 3% 0% Fatigue 1% 0% Nervous System Disorders 5% 3% Headache 3% 1%

12.3 Pharmacokinetics Absorption Zolpidem tartrate disintegrates in the sublingual cavity after administration. On average, zolpidem tartrate is rapidly absorbed in both genders, with a mean T max across studies of about 35 minutes to about 75 minutes. In healthy normal volunteers (age 21 to 45 years) dosed with 3.5 mg zolpidem tartrate, the average C max and AUC were 77 ng/mL and 296 ng·h/mL, respectively in women. The average C max and AUC were 53 ng/mL and 198 ng·h/mL, respectively in men. In women, the average C max and AUC of the 1.75 mg zolpidem tartrate dose were 37 ng/mL and 151 ng·h/mL, respectively. Food decreased the overall C max and AUC of zolpidem tartrate 3.5 mg by 42% and 19%, respectively, and increased the time to peak exposure (T max ) to nearly 3 hours. For optimal effect, zolpidem tartrate should not be administered with or immediately after a meal. Distribution Based on data obtained with oral zolpidem, the total protein binding was found to be 93% ± 0.1% and remained constant independent of concentration between 40 ng/mL and 790 ng/mL. Metabolism Based on data obtained with oral zolpidem, zolpidem tartrate is converted to inactive metabolites that are eliminated primarily by renal excretion. Elimination The elimination half-life of a single-dose of a 3.5 mg zolpidem tartrate sublingual tablet is approximately 2.5 hours (range 1.4 to 3.6 hours). Special Populations Elderly : The recommended dose for Zolpidem tartrate is 1.75 mg. A pharmacokinetic study of 1.75 mg and 3.5 mg doses of zolpidem tartrate showed that the plasma C max and AUC 0-4 hr in elderly subjects following the 3.5 mg dose was higher by 34% and 30%, respectively, than the non-elderly subjects. The C max and AUC of 1.75 mg in elderly subjects were consistently lower than those observed for the 3.5 mg dose in non-elderly subjects but consistently higher than the 1.75 mg dose in non-elderly subjects. The elimination half-life remained unchanged. Hepatic Impairment : The pharmacokinetics of oral zolpidem tartrate in eight patients with chronic hepatic insufficiency were compared to results in subjects with normal hepatic function. Following a single 20 mg oral zolpidem tartrate dose, mean C max and AUC were found to be two times (250 ng/mL vs. 499 ng/mL) and five times (788 ng·hr/mL vs. 4203 ng·hr/mL) higher, respectively, in hepatically compromised patients compared to subjects with normal hepatic function. T max did not change. The mean half-life in cirrhotic patients of 9.9 hr (range: 4.1 to 25.8 hr) was greater than that observed in subjects with normal hepatic function of 2.2 hr (range: 1.6 to 2.4 hr). Dosing should be modified accordingly in patients with hepatic insufficiency [see Dosage and Administration (2.5)]. Renal Impairment: The pharmacokinetics of zolpidem tartrate were studied in 11 patients with end-stage renal failure (mean Cl Cr = 6.5 ± 1.5 mL/min) undergoing hemodialysis three times a week, who were dosed with zolpidem tartrate 10 mg orally each day for 14 or 21 days. No statistically significant differences were observed for C max , T max , half-life, and AUC between the first and last day of drug administration when baseline concentration adjustments were made. Zolpidem was not hemodialyzable. No accumulation of unchanged drug appeared after 14 or 21 days. Zolpidem pharmacokinetics were not significantly different in renally-impaired patients. No dosage adjustment is necessary in patients with renal impairment. Drug Interactions CNS-depressants Co-administration of zolpidem with other CNS depressants increases the risk of CNS depression [see Warnings and Precautions (5.1)]. Zolpidem tartrate was evaluated in healthy volunteers in single-dose interaction studies for several CNS drugs. Imipramine in combination with zolpidem produced no pharmacokinetic interaction other than a 20% decrease in peak levels of imipramine, but there was an additive effect of decreased alertness. Similarly, chlorpromazine in combination with zolpidem produced no pharmacokinetic interaction, but there was an additive effect of decreased alertness and psychomotor performance. A study involving haloperidol and zolpidem revealed no effect of haloperidol on the pharmacokinetics or pharmacodynamics of zolpidem. The lack of a drug interaction following single-dose administration does not predict the absence of an effect following chronic administration. An additive adverse effect on psychomotor performance between alcohol and oral zolpidem was demonstrated [see Warnings and Precautions (5.1)]. Following five consecutive nightly doses at bedtime of oral zolpidem tartrate 10 mg in the presence of sertraline 50 mg (17 consecutive daily doses, at 7:00 am, in healthy female volunteers), zolpidem C max was significantly higher (43%) and T max was significantly decreased (-53%). Pharmacokinetics of sertraline and N-desmethylsertraline were unaffected by zolpidem. A single-dose interaction study with zolpidem tartrate 10 mg and fluoxetine 20 mg at steady-state levels in male volunteers did not demonstrate any clinically significant pharmacokinetic or pharmacodynamic interactions. When multiple doses of zolpidem and fluoxetine were given at steady-state and the concentrations evaluated in healthy females, an increase in the zolpidem half-life (17%) was observed. There was no evidence of an additive effect in psychomotor performance. Drugs that Affect Drug Metabolism via Cytochrome P450 Some compounds known to inhibit CYP3A may increase exposure to zolpidem. The effect of inhibitors of other P450 enzymes on the pharmacokinetics of zolpidem is unknown. A single-dose interaction study with zolpidem tartrate 10 mg and itraconazole 200 mg at steady-state levels in male volunteers resulted in a 34% increase in AUC 0-∞ of zolpidem tartrate. There were no pharmacodynamic effects of zolpidem detected on subjective drowsiness, postural sway, or psychomotor performance. A single-dose interaction study with zolpidem tartrate 10 mg and rifampin 600 mg at steady-state levels in female subjects showed significant reductions of the AUC (-73%), C max (-58%), and T 1/2 (-36 %) of zolpidem together with significant reductions in the pharmacodynamic effects of zolpidem tartrate. Rifampin, a CYP3A4 inducer, significantly reduced the exposure to and the pharmacodynamic effects of zolpidem. A single-dose interaction study with zolpidem tartrate 5 mg and ketoconazole, a potent CYP3A4 inhibitor, given as 200 mg twice daily for 2 days increased C max of zolpidem (30%) and the total AUC of zolpidem (70%) compared to zolpidem alone and prolonged the elimination half-life (30 %) along with an increase in the pharmacodynamic effects of zolpidem. Consideration should be given to using a lower dose of zolpidem when ketoconazole and zolpidem are given together. Other Drugs with No Interactions with Zolpidem A study involving cimetidine/zolpidem tartrate and ranitidine/zolpidem tartrate combinations revealed no effect of either drug on the pharmacokinetics or pharmacodynamics of zolpidem. Zolpidem tartrate had no effect on digoxin pharmacokinetics and did not affect prothrombin time when given with warfarin in healthy subjects.