Dexmedetomidine Hcl

1 INDICATIONS AND USAGE Dexmedetomidine hydrochloride injection is a relatively selective alpha 2 -adrenergic agonist indicated for: Sedation of non-intubated patients prior to and/or during surgical and other procedures. (1.1) 1.1 Procedural Sedation Dexmedetomidine hydrochloride injection is indicated for sedation of non-intubated patients prior to and/or during surgical and other procedures.

2 DOSAGE AND ADMINISTRATION Individualize and titrate dexmedetomidine hydrochloride injection dosing to desired clinical effect. (2.1) Administer dexmedetomidine hydrochloride injection using a controlled infusion device. (2.1) Dilute the 200 mcg/2mL (100 mcg/mL) vial contents in 0.9% sodium chloride solution to achieve required concentration (4 mcg/mL) prior to administration. (2.4) For Adult Procedural Sedation: Generally initiate at one mcg/kg over 10 minutes , followed by a maintenance infusion initiated at 0.6 mcg/kg/ hour and titrated to achieve desired clinical effect with doses ranging from 0.2 to 1 mcg/kg/ hour . (2.2) Alternative doses : recommended for patients over 65 years of age and awake fiberoptic intubation patients. (2.2) 2.1 Dosing Guidelines Dexmedetomidine hydrochloride injection dosing should be individualized and titrated to desired clinical response. Dexmedetomidine hydrochloride injection is not indicated for infusions lasting longer than 24 hours. Dexmedetomidine hydrochloride injection should be administered using a controlled infusion device. 2.2 Dosage Information Table 1: Dosage Information INDICATION DOSAGE AND ADMINISTRATION Initiation of Procedural Sedation For adult patients: a loading infusion of one mcg/kg over 10 minutes . For less invasive procedures such as ophthalmic surgery, a loading infusion of 0.5 mcg/kg given over 10 minutes may be suitable. For awake fiberoptic intubation in adult patients: a loading infusion of one mcg/kg over 10 minutes . For patients over 65 years of age : a loading infusion of 0.5 mcg/kg over 10 minutes [ see Use in Specific Populations (8.5) ] . For adult patients with impaired hepatic function: a dose reduction should be considered [ see Use in Specific Populations (8.6), Clinical Pharmacology (12.3 ) ]. Maintenance of Procedural Sedation For adult patients: the maintenance infusion is generally initiated at 0.6 mcg/kg/ hour and titrated to achieve desired clinical effect with doses ranging from 0.2 to 1 mcg/kg/ hour . The rate of the maintenance infusion should be adjusted to achieve the targeted level of sedation. For awake fiberoptic intubation in adult patients: a maintenance infusion of 0.7 mcg/kg/ hour is recommended until the endotracheal tube is secured. For patients over 65 years of age: a dose reduction should be considered [ see Use in Specific Populations (8.5) ] . For adult patients with impaired hepatic function: a dose reduction should be considered [ see Use in Specific Populations (8.6 ), Clinical Pharmacology (12.3) ]. 2.3 Dosage Adjustment Due to possible pharmacodynamic interactions, a reduction in dosage of dexmedetomidine hydrochloride injection or other concomitant anesthetics, sedatives, hypnotics or opioids may be required when co-administered [see Drug Interactions (7.1)]. Dosage reductions may need to be considered for adult patients with hepatic impairment, and geriatric patients [see Warnings and Precautions (5.7), Use in Specific Populations (8.6 ), Clinical Pharmacology (12.3 )]. 2.4 Preparation of Solution Strict aseptic technique must always be maintained during handling of dexmedetomidine hydrochloride injection. Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit. Dexmedetomidine Hydrochloride Injection, 200 mcg/2 mL (100 mcg/mL) Dexmedetomidine hydrochloride injection must be diluted in 0.9% sodium chloride injection to achieve required concentration (4 mcg/mL) prior to administration. Preparation of solutions is the same, whether for the loading dose or maintenance infusion. To prepare the infusion, withdraw 2 mL of dexmedetomidine hydrochloride injection and add to 48 mL of 0.9% sodium chloride injection to a total of 50 mL. Shake gently to mix well. 2.5 Administration with Other Fluids Dexmedetomidine hydrochloride injection infusion should not be co-administered through the same intravenous catheter with blood or plasma because physical compatibility has not been established. Dexmedetomidine hydrochloride injection has been shown to be incompatible when administered with the following drugs: amphotericin B, diazepam. Dexmedetomidine hydrochloride injection has been shown to be compatible when administered with the following intravenous fluids: 0.9% sodium chloride in water 5% dextrose in water 20% mannitol Lactated Ringer’s solution 100 mg/mL magnesium sulfate solution 0.3% potassium chloride solution 2.6 Compatibility with Natural Rubber Compatibility studies have demonstrated the potential for absorption of dexmedetomidine hydrochloride injection to some types of natural rubber. Although dexmedetomidine hydrochloride injection is dosed to effect, it is advisable to use administration components made with synthetic or coated natural rubber gaskets.

6 ADVERSE REACTIONS The most common adverse reactions (incidence greater than 2%) are hypotension, bradycardia, and dry mouth. (6.1) To report SUSPECTED ADVERSE REACTIONS, contact West-Ward Pharmaceuticals Corp. at 1-877-845-0689, or the FDA at 1-800-FDA-1088 or www.fda.gov/medwatch 6.1 Clinical Studies Experience Because clinical trials are conducted under widely varying conditions, adverse reactions rates observed in the clinical trials of a drug cannot be directly compared to rates in clinical trials of another drug and may not reflect the rates observed in practice. Use of dexmedetomidine hydrochloride has been associated with the following serious adverse reactions: Hypotension, bradycardia and sinus arrest [see Warnings and Precautions (5.2 )] Transient hypertension [see Warnings and Precautions (5.3 )] Most common treatment-emergent adverse reactions, occurring in greater than 2% of patients in procedural sedation studies include hypotension, bradycardia and dry mouth. Procedural Sedation Adverse reaction information is derived from the two trials for procedural sedation [ see Clinical Studies (14.1)] in which 318 adult patients received dexmedetomidine hydrochloride. The mean total dose was 1.6 mcg/kg (range: 0.5 to 6.7), mean dose per hour was 1.3 mcg/kg/hr (range: 0.3 to 6.1) and the mean duration of infusion of 1.5 hours (range: 0.1 to 6.2). The population was between 18 to 93 years of age, ASA I-IV, 30% > 65 years of age, 52% male and 61% Caucasian. Treatment-emergent adverse reactions occurring at an incidence of >2% are provided in Table 2. The most frequent adverse reactions were hypotension, bradycardia, and dry mouth [see Warnings and Precautions (5.2 )] . Pre-­specified criteria for the vital signs to be reported as adverse reactions are footnoted below the table. The decrease in respiratory rate and hypoxia was similar between dexmedetomidine hydrochloride and comparator groups in both studies. Table 2. Adverse Reactions With an Incidence >2%— Procedural Sedation Population Adverse Event Dexmedetomidine hydrochloride N = 318 (%) Placebo N = 113 (%) Hypotension 1 54% 30% Respiratory depression 2 37% 32% Bradycardia 3 14% 4% Hypertension 4 13% 24% Tachycardia 5 5% 17% Nausea 3% 2% Dry mouth 3% 1% Hypoxia 6 2% 3% Bradypnea 2% 4% 1 Hypotension was defined in absolute and relative terms as Systolic blood pressure of <80 mmHg or < 30% lower than pre-study drug infusion value, or Diastolic blood pressure of <50 mmHg 2 Respiratory depression was defined in absolute and relative terms as respiratory rate (RR) <8 beats per minute or >25% decrease from baseline 3 Bradycardia was defined in absolute and relative terms as <40 beats per minute or < 30% lower than pre-study drug infusion value. 4 Hypertension was defined in absolute and relative terms as Systolic blood pressure >180 mmHg or > 30% higher than pre-study drug infusion value or diastolic blood pressure of >100 mmHg. 5 Tachycardia was defined in absolute and relative terms as >120 beats per minute or > 30% greater than pre-study drug infusion value. 6 Hypoxia was defined in absolute and relative terms as SpO 2 <90% or 10% decrease from baseline. 6.2 Postmarketing Experience The following adverse reactions have been identified during post approval use of dexmedetomidine hydrochloride. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Hypotension and bradycardia were the most common adverse reactions associated with the use of dexmedetomidine hydrochloride during post approval use of the drug. Table 3: Adverse Reactions Experienced During Post-approval Use of Dexmedetomidine hydrochloride System Organ Class Preferred Term Blood and Lymphatic System Disorders Anemia Cardiac Disorders Arrhythmia, atrial fibrillation, atrioventricular block, bradycardia, cardiac arrest, cardiac disorder, extrasystoles, myocardial infarction, supraventricular tachycardia, tachycardia, ventricular arrhythmia, ventricular tachycardia Eye Disorders Photopsia, visual impairment Gastrointestinal Disorders Abdominal pain, diarrhea, nausea, vomiting General Disorders and Administration Site Conditions Chills, hyperpyrexia, pain, pyrexia, thirst Hepatobiliary Disorders Hepatic function abnormal, hyperbilirubinemia Investigations Alanine aminotransferase increased, aspartate aminotransferase increased, blood alkaline phosphatase increased, blood urea increased, electrocardiogram T wave inversion, gammaglutamyltransferase increased, electrocardiogram QT prolonged Metabolism and Nutrition Disorders Acidosis, hyperkalemia, hypoglycemia, hypovolemia, hypernatremia Nervous System Disorders Convulsion, dizziness, headache, neuralgia, neuritis, speech disorder Psychiatric Disorders Agitation, confusional state, delirium, hallucination, illusion Renal and Urinary Disorders Oliguria, polyuria Respiratory, Thoracic and Mediastinal Disorders Apnea, bronchospasm, dyspnea, hypercapnia, hypoventilation, hypoxia, pulmonary congestion, respiratory acidosis Skin and Subcutaneous Tissue Disorders Hyperhidrosis Surgical and Medical Procedures Light anesthesia Vascular Disorders Blood pressure fluctuation, hemorrhage, hypertension, hypotension

12.3 Pharmacokinetics Following intravenous administration, dexmedetomidine exhibits the following pharmacokinetic parameters: a rapid distribution phase with a distribution half-life (t 1/2 ) of approximately 6 minutes; a terminal elimination half-life (t 1/2 ) of approximately 2 hours; and steady-state volume of distribution (V ss ) of approximately 118 liters. Clearance is estimated to be approximately 39 L/h. The mean body weight associated with this clearance estimate was 72 kg. Dexmedetomidine exhibits linear pharmacokinetics in the dosage range of 0.2 to 0.7 mcg/kg/hr when administered by intravenous infusion for up to 24 hours. Table 4 shows the main pharmacokinetic parameters when dexmedetomidine hydrochloride was infused (after appropriate loading doses) at maintenance infusion rates of 0.17 mcg/kg/hr (target plasma concentration of 0.3 ng/mL) for 12 and 24 hours, 0.33 mcg/kg/hr (target plasma concentration of 0.6 ng/mL) for 24 hours, and 0.7 mcg/kg/hr (target plasma concentration of 1.25 ng/mL) for 24 hours. Table 4. Mean ± SD Pharmacokinetic Parameters Parameter Loading Infusion (min)/Total infusion duration (hrs) 10 min/12 hrs 10 min/24 hrs 10 min/24 hrs 35 min/24 hrs Dexmedetomidine Target Plasma Concentration (ng/mL) and Dose (mcg/kg/hr) 0.3/0.17 0.3/0.17 0.6/0.33 1.25/0.7 t 1/2 *, hour 1.78 ± 0.3 2.22 ± 0.59 2.23 ± 0.21 2.5 ± 0.61 CL, liter/hour 46.3 ± 8.3 43.1 ± 6.5 35.3 ± 6.8 36.5 ± 7.5 V ss , liter 88.7 ± 22.9 102.4 ± 20.3 93.6 ± 17 99.6 ± 17.8 Avg C ss # , ng/mL 0.27 ± 0.05 0.27 ± 0.05 0.67 ± 0.1 1.37 ± 0.2 * Presented as harmonic mean and pseudo standard deviation. # Mean C ss = Average steady-state concentration of dexmedetomidine hydrochloride. The mean C ss was calculated based on post-dose sampling from 2.5 to 9 hours samples for 12 hour infusion and post-dose sampling from 2.5 to 18 hours for 24 hour infusions. The loading doses for each of the above indicated groups were 0.5, 0.5, 1 and 2.2 mcg/kg, respectively. Dexmedetomidine pharmacokinetic parameters after dexmedetomidine hydrochloride maintenance doses of 0.2 to 1.4 mcg/kg/hr for >24 hours were similar to the PK parameters after dexmedetomidine hydrochloride maintenance dosing for <24 hours in other studies. The values for clearance (CL), volume of distribution (V), and t 1/2 were 39.4 L/hr, 152 L, and 2.67 hours, respectively. Distribution The steady-state volume of distribution (V ss ) of dexmedetomidine was approximately 118 liters. Dexmedetomidine protein binding was assessed in the plasma of normal healthy male and female subjects. The average protein binding was 94% and was constant across the different plasma concentrations tested. Protein binding was similar in males and females. The fraction of dexmedetomidine hydrochloride that was bound to plasma proteins was significantly decreased in subjects with hepatic impairment compared to healthy subjects. The potential for protein binding displacement of dexmedetomidine by fentanyl, ketorolac, theophylline, digoxin and lidocaine was explored in vitro , and negligible changes in the plasma protein binding of dexmedetomidine hydrochloride were observed. The potential for protein binding displacement of phenytoin, warfarin, ibuprofen, propranolol, theophylline and digoxin by dexmedetomidine hydrochloride was explored in vitro and none of these compounds appeared to be significantly displaced by dexmedetomidine hydrochloride. Metabolism Dexmedetomidine undergoes almost complete biotransformation with very little unchanged dexmedetomidine excreted in urine and feces. Biotransformation involves both direct glucuronidation as well as cytochrome P450 mediated metabolism. The major metabolic pathways of dexmedetomidine are: direct N-glucuronidation to inactive metabolites; aliphatic hydroxylation (mediated primarily by CYP2A6) of dexmedetomidine to generate 3-hydroxy-dexmedetomidine, the glucuronide of 3-hydroxy-dexmedetomidine, and 3-carboxy­dexmedetomidine; and N methylation of dexmedetomidine to generate 3-hydroxy N-methyl-dexmedetomidine, 3-carboxy N-methyl-dexmedetomidine, and dexmedetomidine-N-methyl O-glucuronide. Elimination The terminal elimination half-life (t 1/2 ) of dexmedetomidine is approximately 2 hours and clearance is estimated to be approximately 39 L/h. A mass balance study demonstrated that after nine days an average of 95% of the radioactivity, following intravenous administration of radiolabeled dexmedetomidine, was recovered in the urine and 4% in the feces. No unchanged dexmedetomidine was detected in the urine. Approximately 85% of the radioactivity recovered in the urine was excreted within 24 hours after the infusion. Fractionation of the radioactivity excreted in urine demonstrated that products of N-glucuronidation accounted for approximately 34% of the cumulative urinary excretion. In addition, aliphatic hydroxylation of parent drug to form 3-hydroxy­dexmedetomidine, the glucuronide of 3-hydroxy-dexmedetomidine, and 3-carboxylic acid-dexmedetomidine together represented approximately 14% of the dose in urine. N-methylation of dexmedetomidine to form 3 hydroxy N-methyl dexmedetomidine, 3-carboxy N-methyl dexmedetomidine, and N-methyl O-glucuronide dexmedetomidine accounted for approximately 18% of the dose in urine. The N-methyl metabolite itself was a minor circulating component and was undetected in urine. Approximately 28% of the urinary metabolites have not been identified. Gender: There was no observed difference in dexmedetomidine hydrochloride pharmacokinetics due to gender. Geriatrics: The pharmacokinetic profile of dexmedetomidine hydrochloride was not altered by age. There were no differences in the pharmacokinetics of dexmedetomidine hydrochloride in young (18 to 40 years), middle age (41 to 65 years), and elderly (>65 years) subjects. Hepatic Impairment: In subjects with varying degrees of hepatic impairment (Child-Pugh Class A, B, or C), clearance values for dexmedetomidine hydrochloride were lower than in healthy subjects. The mean clearance values for patients with mild, moderate, and severe hepatic impairment were 74%, 64% and 53% of those observed in the normal healthy subjects, respectively. Mean clearances for free drug were 59%, 51% and 32% of those observed in the normal healthy subjects, respectively. Although dexmedetomidine hydrochloride is dosed to effect, it may be necessary to consider dose reduction in subjects with hepatic impairment [see Dosage and Administration (2.2), Warnings and Precautions (5.7 )]. Renal Impairment: Dexmedetomidine pharmacokinetics (C max , T max , AUC, t 1/2 , CL, and V ss ) were not significantly different in patients with severe renal impairment (creatinine clearance: <30 mL/min) compared to healthy subjects. Drug Interactions: In vitro studies: In vitro studies in human liver microsomes demonstrated no evidence of cytochrome P450 mediated drug interactions that are likely to be of clinical relevance.