Xyrem(Sodium Oxybate) and Ambien(Zolpidem Tartrate) in the Treatment of Chronic Insomnia.

• 1. To assess the long term efficacy of sodium oxybate and zolpidem tartrate in reducing insomnia and
• improving sleep quality.

• Secondary aims:
• To compare the magnitude of sleep improvement sodium oxybate produces with that of zolpidem tartrate.
• To compare and contrast the profile of effects of oxybate and zolpidem on sleep architecture, sleep
• latency, wake after sleep onset, and sleep efficiency.
• To explore the extent to which sodium oxybate and zolpidem tartrate improve daytime functions that are
• adversely affected by poor/inadequate sleep.
• To assess the extent of rebound insomnia that is associated with abrupt discontinuation of sodium oxybate
• and zolpidem tartrate.

The primary purpose of the study is to evaluate the long term efficacy of sodium oxybate (Xyrem®) and zolpidem tartrate (Ambien®) in treating chronic insomnia. We will compare the efficacy of sodium oxybate with zolpidem tartrate (Ambien®), and compare the efficacy of each of these two medications with placebos.

Primary aim:

1. To assess the long term efficacy of sodium oxybate and zolpidem tartrate in reducing insomnia and improving sleep quality.

Secondary aims:

To compare the magnitude of sleep improvement sodium oxybate produces with that of zolpidem tartrate.

To compare and contrast the profile of effects of oxybate and zolpidem on sleep architecture, sleep latency, wake after sleep onset, and sleep efficiency.

To explore the extent to which sodium oxybate and zolpidem tartrate improve daytime functions that are adversely affected by poor/inadequate sleep.

To assess the extent of rebound insomnia that is associated with abrupt discontinuation of sodium oxybate and zolpidem tartrate.

• Drug: zolpidem tartrate
• Drug: sodium oxybate
• Drug: Matching Placebos

Inclusion Criteria:

1. Written informed consent is obtained.
2. The patient is an outpatient, man or woman of any ethnic origin, 18-75 years of age (inclusive).
3. Patient reports insomnia for at least six months, and insomnia causes the patient distress.
4. The Investigator determines that the patient meets diagnostic criteria for Chronic Insomnia according to International Classification of Sleep Disorders (ICSD) criteria.
5. Sleep diary based screening shows sleep onset latency >30 minutes, and /or wake after sleep onset >30 minutes per night at least 3 nights per week, with combined wake-time-in-bed _> 45 minutes.
6. The patient is in good health as determined by a medical and psychiatric history, and physical examination.
7. Women must be surgically sterile, 2 years post-menopausal, or if of child-bearing potential, using a medically accepted method of birth control, and agree to continued use of this method for the duration of the study.
8. The patient is willing and able to comply with study restrictions and to attend regularly scheduled clinic visits as specified in this protocol.

Exclusion Criteria:

1. Has any clinically significant, uncontrolled medical or psychiatric conditions. (treated or untreated)
2. Has a probable diagnosis of a current sleep disorder other than Chronic Insomnia.
3. Used any prescription drugs disallowed by the protocol or clinically significant use of over-the counter(OTC) drugs within 14 days before the screening visit.
4. Has a history of alcohol, narcotic, or any other abuse as defined by the DSM-V.
5. Has a clinically significant deviation from normal in the physical examination.
6. Is a pregnant or lactating woman. (Any woman becoming pregnant during the study will be withdrawn from the study.)
7. Has any disorder that may interfere with drug absorption, distribution, metabolism, or excretion (including gastrointestinal surgery and succinic semialdehyde dehydrogenase deficiency)
8. Has a known clinically significant drug sensitivity to sodium oxybate or sedative hypnotics.