sodium oxybate

1 INDICATIONS AND USAGE Sodium oxybate oral solution is indicated for the treatment of cataplexy or excessive daytime sleepiness (EDS) in patients with narcolepsy. Pediatric use information is approved for Jazz Pharmaceuticals Inc.’s XYREM (sodium oxybate) Oral Solution. However, due to Jazz Pharmaceuticals Inc.’s marketing exclusivity rights, this drug product is not labeled with that pediatric information. Sodium oxybate oral solutio n is a central nervous system depressant indicated for the treatment of cataplexy or excessive daytime sleepiness (EDS) in patients with narcolepsy (1).

2 DOSAGE AND ADMINISTRATION Dosage for Adult Patients Initiate dosage at 4.5 g per night orally, divided into two doses ( 2.1 ). Titrate to effect in increments of 1.5 g per night at weekly intervals (0.75 g at bedtime and 0.75 g taken 2.5 to 4 hours later) ( 2.1 ). Recommended dosage range: 6 g to 9 g per night orally ( 2.1 ). Total Nightly Dose Take at Bedtime Take 2.5 to 4 Hours Later 4.5 g per night 2.25 g 2.25 g 6 g per night 3 g 3 g 7.5 g per night 3.75 g 3.75 g 9 g per night 4.5 g 4.5 g Important Administration Information Prepare both doses prior to bedtime; dilute each dose with approximately ¼ cup of water in pharmacy-provided containers ( 2.3 ). Allow 2 hours after eating before dosing ( 2.3 ). Take each dose while in bed and lie down after dosing ( 2.3 ). Patients with Hepatic Impairment Recommended starting dosage is one-half of the original dosage per night administered orally, divided into two doses ( 2.4 ). 2.1 Adult Dosing Information The recommended starting dosage is 4.5 grams (g) per night administered orally, divided into two doses: 2.25 g at bedtime and 2.25 g taken 2.5 to 4 hours later (see Table 1). Increase the dosage by 1.5 g per night at weekly intervals (additional 0.75 g at bedtime and 0.75 g taken 2.5 to 4 hours later) to the effective dosage range of 6 g to 9 g per night orally. The dosage may be gradually titrated based on efficacy and tolerability. Doses higher than 9 g per night have not been studied and should not ordinarily be administered. Table 1: Recommended Adult Sodium oxybate oral solution Dose Regimen (g = grams) If a Patient’s Total Nightly Dose is: Take at Bedtime: Take 2.5 to 4 Hours Later: 4.5 g per night 2.25 g 2.25 g 6 g per night 3 g 3 g 7.5 g per night 3.75 g 3.75 g 9 g per night 4.5 g 4.5 g Pediatric use information is approved for Jazz Pharmaceuticals Inc.’s XYREM (sodium oxybate) Oral Solution. However, due to Jazz Pharmaceuticals Inc.’s marketing exclusivity rights, this drug product is not labeled with that pediatric information. 2.3 Important Administration Instructions for All Patients The total nightly dosage of sodium oxybate oral solution is divided into two doses. Prepare both doses of sodium oxybate oral solution prior to bedtime. Prior to ingestion, each dose of sodium oxybate oral solution should be diluted with approximately ¼ cup (approximately 60 mL) of water in the empty pharmacy containers provided. Take the first nightly dose of sodium oxybate oral solution at least 2 hours after eating [see Clinical Pharmacology (12.3)]. Take the second nightly dose 2.5 to 4 hours after the first dose. Patients should take both doses of sodium oxybate oral solution while in bed and lie down immediately after dosing, and remain in bed following ingestion of each dose. Sodium oxybate oral solution may cause patients to fall asleep abruptly without first feeling drowsy [see Adverse Reactions (6.2)]. Patients will often fall asleep within 5 minutes of taking sodium oxybate oral solution, and will usually fall asleep within 15 minutes, though the time it takes any individual patient to fall asleep may vary from night to night. Patients may need to set an alarm to awaken for the second dose. Rarely, patients may take up to 2 hours to fall asleep. If the second dose is missed, that dose should be skipped and sodium oxybate oral solution should not be taken again until the next night. Both sodium oxybate oral solution doses should never be taken at one time. 2.4 Dosage Modification in Patients with Hepatic Impairment The recommended starting dosage in patients with hepatic impairment is one-half of the original dosage per night, administered orally divided into two doses [see Use in Specific Populations (8.6) and Clinical Pharmacology (12.3)]. 2.5 Dosage Adjustment with Co-administration of Divalproex Sodium When initiating divalproex sodium in patients taking a stable dosage of sodium oxybate oral solution, a reduction of the sodium oxybate oral solution dosage by at least 20% is…

5 WARNINGS AND PRECAUTIONS CNS depression: Use caution when considering the concurrent use of sodium oxybate oral solution with other CNS depressants (5.1). Caution patients against hazardous activities requiring complete mental alertness or motor coordination within the first 6 hours of dosing or after first initiating treatment until certain that sodium oxybate oral solution does not affect them adversely (5.1). Depression and suicidality: Monitor patients for emergent or increased depression and suicidality (5.5). Confusion/Anxiety: Monitor for impaired motor/cognitive function (5.6). Parasomnias: Evaluate episodes of sleepwalking (5.7). High sodium content in sodium oxybate oral solution: Monitor patients with heart failure, hypertension, or impaired renal function (5.8). 5.1 Central Nervous System Depression Sodium oxybate is a central nervous system (CNS) depressant. In adult clinical trials at recommended doses, obtundation and clinically significant respiratory depression occurred in patients treated with sodium oxybate oral solution. Sodium oxybate oral solution is contraindicated in combination with alcohol and sedative hypnotics. The concurrent use of sodium oxybate oral solution with other CNS depressants, including but not limited to opioid analgesics, benzodiazepines, sedating antidepressants or antipsychotics, sedating anti-epileptic drugs, general anesthetics, muscle relaxants, and/or illicit CNS depressants, may increase the risk of respiratory depression, hypotension, profound sedation, syncope, and death. If use of these CNS depressants in combination with sodium oxybate oral solution is required, dose reduction or discontinuation of one or more CNS depressants (including sodium oxybate oral solution) should be considered. In addition, if short-term use of an opioid (e.g., post- or perioperative) is required, interruption of treatment with sodium oxybate oral solution should be considered. Healthcare providers should caution patients about operating hazardous machinery, including automobiles or airplanes, until they are reasonably certain that sodium oxybate oral solution does not affect them adversely (e.g., impair judgment, thinking, or motor skills). Patients should not engage in hazardous occupations or activities requiring complete mental alertness or motor coordination, such as operating machinery or a motor vehicle or flying an airplane, for at least 6 hours after taking sodium oxybate oral solution. Patients should be queried about CNS depression-related events upon initiation of sodium oxybate oral solution therapy and periodically thereafter. Sodium oxybate oral solution is available only through a restricted program under a REMS [see Warnings and Precautions (5.3)]. 5.2 Abuse and Misuse Sodium oxybate oral solution is a Schedule III controlled substance. The active ingredient of sodium oxybate oral solution, sodium oxybate or gamma-hydroxybutyrate (GHB), is a Schedule I controlled substance. Abuse of illicit GHB, either alone or in combination with other CNS depressants, is associated with CNS adverse reactions, including seizure, respiratory depression, decreases in the level of consciousness, coma, and death. The rapid onset of sedation, coupled with the amnestic features of sodium oxybate oral solution, particularly when combined with alcohol, has proven to be dangerous for the voluntary and involuntary user (e.g., assault victim). Because illicit use and abuse of GHB have been reported, physicians should carefully evaluate patients for a history of drug abuse and follow such patients closely, observing them for signs of misuse or abuse of GHB (e.g., increase in size or frequency of dosing, drug-seeking behavior, feigned cataplexy) [see Drug Abuse and Dependence (9.2)]. Sodium oxybate oral solution is available only through a restricted program under a REMS [see Warnings and Precautions (5.3)]. 5.3 Sodium Oxybate REMS Program Sodium oxybate oral solution is available only through a restricted d…

4 CONTRAINDICATIONS Sodium oxybate oral solution is contraindicated for use in: combination with sedative hypnotics [see Warnings and Precautions (5.1)]. combination with alcohol [see Warnings and Precautions (5.1)]. patients with succinic semialdehyde dehydrogenase deficiency [see Clinical Pharmacology (12.3)]. In combination with sedative hypnotics or alcohol ( 4 ) Succinic semialdehyde dehydrogenase deficiency ( 4 )

7 DRUG INTERACTIONS Concomitant use with divalproex sodium: An initial reduction in sodium oxybate oral solution dose of at least 20% is recommended (2.5, 7.2). 7.1 Alcohol, Sedative Hypnotics, and CNS Depressants Sodium oxybate oral solution is contraindicated for use in combination with alcohol or sedative hypnotics. Use of other CNS depressants may potentiate the CNS-depressant effects of sodium oxybate oral solution [see Warnings and Precautions (5.1)]. 7.2 Divalproex Sodium Concomitant use of sodium oxybate oral solution with divalproex sodium results in an increase in systemic exposure to GHB, which was shown to cause a greater impairment on some tests of attention and working memory in a clinical study [see Clinical Pharmacology (12.3)]. An initial dose reduction of sodium oxybate oral solution is recommended when used concomitantly with divalproex sodium [see Dosage and Administration (2.5)]. Prescribers are advised to monitor patient response closely and adjust dose accordingly if concomitant use of sodium oxybate oral solution and divalproex sodium is warranted.

8.1 Pregnancy Risk Summary There are no adequate data on the developmental risk associated with the use of sodium oxybate in pregnant women. Oral administration of sodium oxybate to pregnant rats (150, 350, or 1,000 mg/kg/day) or rabbits (300, 600, or 1,200 mg/kg/day) throughout organogenesis produced no clear evidence of developmental toxicity; however, oral administration to rats throughout pregnancy and lactation resulted in increased stillbirths and decreased offspring postnatal viability and growth, at a clinically relevant dose [see Data] . In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively. The background risk of major birth defects and miscarriage for the indicated population is unknown. Clinical Considerations Labor or Delivery Sodium oxybate oral solution has not been studied in labor or delivery. In obstetric anesthesia using an injectable formulation of sodium oxybate, newborns had stable cardiovascular and respiratory measures but were very sleepy, causing a slight decrease in Apgar scores. There was a fall in the rate of uterine contractions 20 minutes after injection. Placental transfer is rapid and gamma-hydroxybutyrate (GHB) has been detected in newborns at delivery after intravenous administration of GHB to mothers. Subsequent effects of sodium oxybate on later growth, development, and maturation in humans are unknown. Data Animal Data Oral administration of sodium oxybate to pregnant rats (150, 350, or 1,000 mg/kg/day) or rabbits (300, 600, or 1,200 mg/kg/day) throughout organogenesis produced no clear evidence of developmental toxicity. The highest doses tested in rats and rabbits were approximately 1 and 3 times, respectively, the maximum recommended human dose (MRHD) of 9 g per night on a body surface area (mg/m 2 ) basis. Oral administration of sodium oxybate (150, 350, or 1,000 mg/kg/day) to rats throughout pregnancy and lactation resulted in increased stillbirths and decreased offspring postnatal viability and body weight gain at the highest dose tested. The no-effect dose for pre- and post­natal developmental toxicity in rats is less than the MRHD on a mg/m 2 basis.

6 ADVERSE REACTIONS The following clinically significant adverse reactions appear in other sections of the labeling: CNS depression [see Warnings and Precautions (5.1)] Abuse and Misuse [see Warnings and Precautions (5.2)] Respiratory Depression and Sleep-Disordered Breathing [see Warnings and Precautions (5.4)] Depression and Suicidality [see Warnings and Precautions (5.5)] Other Behavioral or Psychiatric Adverse Reactions [see Warnings and Precautions (5.6)] Parasomnias [see Warnings and Precautions (5.7)] Use in Patients Sensitive to High Sodium Intake [see Warnings and Precautions (5.8)] Most common adverse reactions in adults (≥5% and at least twice the incidence with placebo) were nausea, dizziness, vomiting, somnolence, enuresis, and tremor (6.1). To report SUSPECTED ADVERSE REACTIONS, contact Camber Pharmaceuticals, Inc. at 1-866-495-8330, or FDA at 1-800-FDA-1088 or www.fda.gov/Medwatch. 6.1 Clinical Trials Experience 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 clinical practice. Adult Patients Sodium oxybate oral solution was studied in three placebo-controlled clinical trials (Trials N1, N3, and N4, described in Sections 14.1 and 14.2) in 611 patients with narcolepsy (398 subjects treated with sodium oxybate oral solution, and 213 with placebo). A total of 781 patients with narcolepsy were treated with sodium oxybate oral solution in controlled and uncontrolled clinical trials. Section 6.1 and Table 4 present adverse reactions from three pooled, controlled trials (N1, N3, N4) in patients with narcolepsy. Adverse Reactions Leading to Treatment Discontinuation: Of the 398 patients with narcolepsy treated with sodium oxybate oral solution, 10.3% of patients discontinued because of adverse reactions compared with 2.8% of patients receiving placebo. The most common adverse reaction leading to discontinuation was nausea (2.8%). The majority of adverse reactions leading to discontinuation began during the first few weeks of treatment. Commonly Observed Adverse Reactions in Controlled Clinical Trials: The most common adverse reactions (incidence ≥5% and twice the rate seen with placebo) in patients treated with sodium oxybate oral solution were nausea, dizziness, vomiting, somnolence, enuresis, and tremor. Adverse Reactions Occurring at an Incidence of 2% or Greater: Table 4 lists adverse reactions that occurred at a frequency of 2% or more in any treatment group for three controlled trials and were more frequent in any sodium oxybate oral solution treatment group than with placebo. Adverse reactions are summarized by dose at onset. Nearly all patients in these studies initiated treatment at 4.5 g per night. In patients who remained on treatment, adverse reactions tended to occur early and to diminish over time. Table 4 Adverse Reactions Occurring in ≥2% of Adult Patients and More Frequently with Sodium oxybate oral solution than Placebo in Three Controlled Trials (N1, N3, N4) by Body System and Dose at Onset Adverse Reaction Placebo (n=213) % Sodium oxybate oral solution 4.5g (n=185) % Sodium oxybate oral solution 6g (n=258) % Sodium oxybate oral solution 9g (n=178) % ANY ADVERSE REACTION 62 45 55 70 GASTROINTESTINAL DISORDERS Nausea 3 8 13 20 Vomiting 1 2 4 11 Diarrhea 2 4 3 4 Abdominal pain upper 2 3 1 2 Dry mouth 2 1 2 1 GENERAL DISORDERS AND ADMINISTRATIVE SITE CONDITIONS Pain 1 1 <1 3 Feeling drunk 1 0 <1 3 Edema peripheral 1 3 0 0 MUSCULOSKELETAL AND CONNECTIVE TISSUE DISORDERS Cataplexy 1 1 1 2 Muscle spasms 2 2 <1 2 Pain in extremity 1 3 1 1 NERVOUS SYSTEM DISORDERS Dizziness 4 9 11 15 Somnolence 4 1 3 8 Tremor 0 0 2 5 Disturbance in attention 0 1 0 4 Paresthesia 1 2 1 3 Sleep paralysis 1 0 1 3 PSYCHIATRIC DISORDERS Disorientation 1 1 2 3 Irritability 1 0 <1 3 Sleepwalking 0 0 0 3 Anxiety 1 1 1 2 RENAL AND UR…