amiodarone hydrochloride

1 INDICATIONS AND USAGE Amiodarone Hydrochloride Injection, USP is indicated for initiation of treatment and prophylaxis of frequently recurring ventricular fibrillation (VF) and hemodynamically unstable ventricular tachycardia (VT) in patients refractory to other therapy. Amiodarone Hydrochloride Injection, USP also can be used to treat patients with VT/VF for whom oral amiodarone is indicated, but who are unable to take oral medication. During or after treatment with Amiodarone Hydrochloride Injection, USP patients may be transferred to oral amiodarone therapy [see Dosage and Administration ( 2 )] . Use Amiodarone Hydrochloride Injection, USP for acute treatment until the patient's ventricular arrhythmias are stabilized. Most patients will require this therapy for 48 to 96 hours, but Amiodarone Hydrochloride Injection may be safely administered for longer periods if necessary. Amiodarone Hydrochloride Injection, USP is an antiarrhythmic agent indicated for initiation of treatment and prophylaxis of frequently recurring ventricular fibrillation (VF) and hemodynamically unstable ventricular tachycardia (VT) in patients refractory to other therapy. ( 1 )

2 DOSAGE & ADMINISTRATION Amiodarone shows considerable interindividual variation in response. Although a starting dose adequate to suppress life-threatening arrhythmias is needed, close monitoring with adjustment of dose is essential. The recommended starting dose of amiodarone is about 1000 mg over the first 24 hours of therapy, delivered by the following infusion regimen: Table 1: AMIODARONE DOSE RECOMMENDATIONS: FIRST 24 HOURS After the first 24 hours, continue the maintenance infusion rate of 0.5 mg/min (720 mg per 24 hours) utilizing a concentration of 1 mg/mL to 6 mg/mL (Use a central venous catheter for amiodarone concentrations greater than 2 mg/mL). The rate of the maintenance infusion may be increased to achieve effective arrhythmia suppression. In the event of breakthrough episodes of VF or hemodynamically unstable VT, use 150 mg supplemental infusions of amiodarone (mixed in 100 mL of D5W and infused over 10 minutes to minimize the potential for hypotension). The first 24-hour dose may be individualized for each patient; however, in controlled clinical trials, mean daily doses above 2100 mg were associated with an increased risk of hypotension. Do not exceed an initial infusion rate of 30 mg/min. Based on the experience from clinical studies of intravenous amiodarone, a maintenance infusion of up to 0.5 mg/min can be continued for 2 to 3 weeks regardless of the patient's age, renal function, or left ventricular function. There has been limited experience in patients receiving intravenous amiodarone for longer than 3 weeks. The surface properties of solutions containing injectable amiodarone are altered such that the drop size may be reduced. This reduction may lead to underdosage of the patient by up to 30% if drop counter infusion sets are used. Amiodarone must be delivered by a volumetric infusion pump. Administer amiodarone, whenever possible, through a central venous catheter dedicated to that purpose. Use an in-line filter during administration. Intravenous amiodarone loading infusions at much higher concentrations and rates of infusion much faster than recommended have resulted in hepatocellular necrosis and acute renal failure, leading to death [see Warnings and Precautions ( 5-( 5.3))]. Intravenous amiodarone concentrations greater than 3 mg/mL in D5W have been associated with a high incidence of peripheral vein phlebitis; however, concentrations of 2.5 mg/mL or less appear to be less irritating. Therefore, for infusions longer than 1 hour, do not exceed amiodarone concentrations of 2 mg/mL, unless a central venous catheter is used [see Adverse Reactions ( 6-( 6.2))]. Amiodarone infusions exceeding 2 hours must be administered in glass or polyolefin bottles containing D5W. Do not use evacuated glass containers for admixing, as incompatibility with a buffer in the container may cause precipitation. Amiodarone adsorbs to polyvinyl chloride (PVC) tubing, but all of the clinical experience has been with PVC tubing and the concentrations and rates of infusion provided in Dosage & Administration reflect dosing in these studies. Amiodarone has been found to leach out plasticizers, including DEHP [di-(2-ethylhexyl)phthalate] from intravenous tubing (including PVC tubing). The degree of leaching increases when infusing amiodarone at higher concentrations and lower flow rates than provided in DOSAGE AND ADMINISTRATION. Polysorbate 80, a component of amiodarone hydrochloride injection, is also known to leach DEHP from PVC [see Description ( 11 )]. Amiodarone does not need to be protected from light during administration. NOTE: Inspect parenteral drug products for particulate matter and discoloration prior to administration, whenever solution and container permit – solution should be clear. CAUTION: Do not use plastic containers in series connections. Such use could result in air embolism due to residual air being drawn from the primary container before the administration of the fluid from the secondary container is c …

3 DOSAGE FORMS AND STRENGTHS Amiodarone Hydrochloride Injection, USP, 50 mg/mL Amiodarone Hydrochloride Injection, USP, 50 mg/mL

4 CONTRAINDICATIONS Amiodarone is contraindicated in patients with: • Known hypersensitivity to any of the components of Amiodarone Hydrochloride Injection, USP, including iodine. Hypersensitivity reactions may involve rash, angioedema, cutaneous/mucosal hemorrhage (bleeding), fever, arthralgias (joint pains), eosinophilia (abnormal blood counts), urticaria (hives), thrombotic thrombocytopenic purpura, or severe periateritis (inflammation around blood vessels) • Cardiogenic shock • Marked sinus bradycardia • Second- or third-degree atrio-ventricular (AV) block unless of a functioning pacemaker is available. Amiodarone is contraindicated in patients with (4): • Known hypersensitivity to any of the components of amiodarone, including iodine • Cardiogenic shock • Marked sinus bradycardia • Second- or third-degree atrio-ventricular (AV) block unless of a functioning pacemaker is available.

6 ADVERSE REACTIONS The following adverse reactions are described elsewhere in labeling: • Hypotension [see Warnings and Precautions ( 5.1 )] • Hepatic injury [see Warnings and Precautions ( 5.3 )] • Rhythm disturbances [see Warnings and Precautions ( 5.4 )] • Pulmonary injury [see Warnings and Precautions ( 5.5 )] • Thyroid injury [see Warnings and Precautions ( 5.7 )] • Hypersensitivity [see Warnings and Precautions ( 5.11 )] • The most common adverse reactions (1-2%) leading to discontinuation of intravenous amiodarone therapy are hypotension, asystole/cardiac arrest/pulseless electrical activity, VT, and cardiogenic shock. ( 6 ) • Other important adverse reactions are, torsade de pointes, congestive heart failure, and liver function test abnormalities. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Fresenius Kabi USA, LLC at 1-800-551-7176 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 practice. In a total of 1836 patients in controlled and uncontrolled clinical trials, 14% of patients received intravenous amiodarone for at least one week, 5% received it for at least 2 weeks, 2% received it for at least 3 weeks, and 1% received it for more than 3 weeks, without an increased incidence of severe adverse reactions. The mean duration of therapy in these studies was 5.6 days; median exposure was 3.7 days. The most important adverse reactions were hypotension, asystole/cardiac arrest/pulseless electrical activity (PEA), cardiogenic shock, congestive heart failure, bradycardia, liver function test abnormalities, VT, and AV block. Overall, treatment was discontinued for about 9% of the patients because of adverse reactions. The most common adverse reactions leading to discontinuation of intravenous amiodarone therapy were hypotension (1.6%), asystole/cardiac arrest/PEA (1.2%), VT (1.1%), and cardiogenic shock (1%). Table 5 lists the most common (incidence ≥2%) adverse reactions during intravenous amiodarone therapy considered at least possibly drug-related. These data were collected in clinical trials involving 1836 patients with life-threatening VT/VF. Data from all assigned treatment groups are pooled because none of the adverse reactions appeared to be dose-related. Table 5: ADVERSE REACTIONS IN PATIENTS RECEIVING INTRAVENOUS AMIODARONE IN CONTROLLED AND OPEN-LABEL STUDIES (≥ 2% INCIDENCE) Controlled Open-Label Study Event Studies Studies Total (n = 814) (n = 1022) (n = 1836) Body as a whole Fever 24 (2.9%) 13 (1.2%) 37 (2.0%) Cardiovascular System Bradycardia 49 (6.0%) 41 (4.0%) 90 (4.9%) Congestive heart failure 18 (2.2%) 21 (2.0%) 39 (2.1%) Heart arrest 29 (3.5%) 26 (2.5%) 55 (2.9%) Hypotension 165 (20.2%) 123 (12.0%) 288 (15.6%) Ventricular tachycardia 15 (1.8%) 30 (2.9%) 45 (2.4%) Digestive System Liver function tests abnormal 35 (4.2%) 29 (2.8%) 64 (3.4%) Nausea 29 (3.5%) 43 (4.2%) 72 (3.9%) Other adverse reactions reported in less than 2% of patients receiving intravenous amiodarone in controlled and uncontrolled studies included the following: abnormal kidney function, atrial fibrillation, diarrhea, increased ALT, increased AST, lung edema, nodal arrhythmia, prolonged QT interval, respiratory disorder, shock, sinus bradycardia, Stevens-Johnson syndrome, thrombocytopenia, VF, and vomiting. 6.2 Post-Marketing Experience The following adverse reactions have been reported in the post-marketing experience during or in close temporal relationship to intravenous amiodarone administration. 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. Blood and Lymphatic System Disorders: pancytopenia, …

7 Drug Interactions Amiodarone is metabolized to the active metabolite desethylamiodarone by the cytochrome P450 (CYP450) enzyme group, specifically cytochromes P4503A4 (CYP3A) and CYP2C8. The CYP3A isoenzyme is present in both the liver and intestines. Amiodarone is an inhibitor of CYP3A. Therefore, amiodarone has the potential for interactions with drugs or substances that may be substrates, inhibitors or inducers of CYP3A. While only a limited number of in vivo drug-drug interactions with amiodarone have been reported, chiefly with the oral formulation, the potential for other interactions should be anticipated. This is especially important for drugs associated with serious toxicity, such as other antiarrhythmics. If such drugs are needed, reassess their dose and, where appropriate, measure plasma concentrations. In view of the long and variable half-life of amiodarone, potential for drug interactions exists not only with concomitant medication but also with drugs administered after discontinuation of amiodarone. Since amiodarone is a substrate for CYP3A and CYP2C8, drugs/substances that inhibit these isoenzymes may decrease the metabolism and increase serum concentration of amiodarone. Reported examples include the following: Protease inhibitors: Protease inhibitors are known to inhibit CYP3A to varying degrees. A case report of one patient taking amiodarone 200 mg and indinavir 800 mg three times a day resulted in increases in amiodarone concentrations from 0.9 mg/L to 1.3 mg/L. DEA concentrations were not affected. There was no evidence of toxicity. Consider monitoring for amiodarone toxicity and serial measurement of amiodarone serum concentration during concomitant protease inhibitor therapy. Histamine H 1 antagonists: Loratadine, a non-sedating antihistaminic, is metabolized primarily by CYP3A. QT interval prolongation and TdP have been reported with the coadministration of loratadine and amiodarone. Histamine H 2 antagonists: Cimetidine inhibits CYP3A and can increase serum amiodarone levels. Antidepressants: Trazodone, an antidepressant, is metabolized primarily by CYP3A. QT interval prolongation and TdP have been reported with the coadministration of trazodone and amiodarone. Other substances: Grapefruit juice given to healthy volunteers increased amiodarone AUC by 50% and C max by 84%, resulting in increased plasma levels of amiodarone. Do not take grapefruit juice during treatment with amiodarone. Amiodarone inhibits p-glycoprotein and certain CYP450 enzymes, including CYP1A2, CYP2C9, CYP2D6, and CYP3A. This inhibition can result in unexpectedly high plasma levels of other drugs which are metabolized by those CYP450 enzymes or are substrates for p-glycoprotein. Reported examples of this interaction include the following: Immunosuppressives: Cyclosporine (CYP3A substrate) administered in combination with oral amiodarone has been reported to produce persistently elevated plasma concentrations of cyclosporine resulting in elevated creatinine, despite reduction in dose of cyclosporine. HMG-CoA Reductase Inhibitors: Simvastatin (CYP3A substrate) in combination with amiodarone has been associated with reports of myopathy/rhabdomyolysis. Cardiovasculars: Cardiac glycosides: In patients receiving digoxin therapy, administration of oral amiodarone regularly results in an increase in serum digoxin concentration that may reach toxic levels with resultant clinical toxicity. Amiodarone taken concomitantly with digoxin increases the serum digoxin concentration by 70% after one day. On administration of oral amiodarone, review the need for digitalis therapy and reduce the dose of digitalis by approximately 50% or discontinue digitalis. If digitalis treatment is continued, monitor serum levels closely and observe patients for clinical evidence of toxicity. Antiarrhythmics: Other antiarrhythmic drugs, such as quinidine, procainamide, disopyramide, and phenytoin, have been used concurrently with amiodarone. There have been case re …

8 USE IN SPECIFIC POPULATIONS • Pregnancy: Use amiodarone during pregnancy only if the potential benefit to the mother justifies the risk to the fetus ( 8.1 ). • Nursing mothers: Advise mothers to discontinue breast feeding ( 8.3 ). • Pediatric use: Safety and efficacy have not been established ( 8.4 ). 8.1 Pregnancy Pregnancy Category D [see Warnings and Precautions (5.8) ] . Teratogenic Effects Amiodarone and desethylamiodarone cross the placenta. Reported risks include: • neonatal bradycardia, QT prolongation, and periodic ventricular extrasystoles • neonatal hypothyroidism (with or without goiter) detected antenatally or in the newborn and reported even after a few days of exposure • neonatal hyperthyroxinemia • neurodevelopmental abnormalities independent of thyroid function, including speech delay and difficulties with written language and arithmetic, delayed motor development, and ataxia. • jerk nystagmus with synchronous head titubation • fetal growth retardation • premature birth Amiodarone has caused a variety of adverse effects in animals. Amiodarone was given intravenously to rabbits at dosages of 5 mg/kg per day, 10 mg/kg per day, or 25 mg/kg per day (about 0.1, 0.3, and 0.7 times the human intravenous maintenance dose of 0.5 mg/min on a body surface area basis), during gestation days 8 to 16 (organogenesis). The incidence of maternal deaths increased with increasing dose and occurred in all treated groups, and controls. Mean fetal weights were significantly decreased in the low and middle dose groups and embryotoxicity (as manifested by fewer full- term fetuses and increased resorptions) occurred at dosages of 10 mg/kg and above. There were no significant differences in the number of minor fetal abnormalities and no major fetal abnormalities were observed. Amiodarone was administered by continuous intravenous infusion to rats at dosages of 25 mg/kg per day, 50 mg/kg per day, or 100 mg/kg per day (about 0.3, 0.7, and 1.3 times the human intravenous maintenance dose of 0.5 mg/min on a body surface area basis) during gestation days 8 to 16 (organogenesis). Maternal toxicity (manifest as reduced weight gain and food consumption) and embryotoxicity (manifest as increased resorptions, decreased live litter size and fetal body weights, and delayed sternal and metacarpal ossification) were observed in the 100 mg/kg group. The delayed ossification was reversible and related to decreased fetal weight. Fetal thyroid tissues appeared normal in all groups. Nonteratogenic Effects Very high concentrations of amiodarone and desethylamiodarone may be found in testes. Elevated follicle-stimulating hormone and luteinizing hormone levels, suggestive of testicular dysfunction, have been reported in men on long-term amiodarone treatment. While planning pregnancy after discontinuation of amiodarone treatment, consider the long half-life of amiodarone and its metabolite DEA. 8.2 Labor and Delivery It is not known whether the use of amiodarone during labor or delivery has any immediate or delayed adverse effects. Preclinical studies in rodents have not shown any effect on the duration of gestation or on parturition. 8.3 Nursing Mothers Amiodarone and one of its major metabolites, desethylamiodarone (DEA), are excreted in human milk, suggesting that breast-feeding could expose the nursing infant to a significant dose of the drug. Nursing offspring of lactating rats administered amiodarone have demonstrated reduced viability and reduced body weight gains. The risk of exposing the infant to amiodarone must be weighed against the potential benefit of arrhythmia suppression in the mother. Advise the mother to discontinue nursing. 8.4 Pediatric Use The safety and effectiveness of amiodarone in pediatric patients have not been established; therefore, the use of amiodarone in pediatric patients is not recommended. In a pediatric trial of 61 patients, aged 30 days to 15 years, hypotension (36%), bradycardia (20%), and AV block (15%) were common d …

12.1 Mechanism of Action Amiodarone is generally considered a class III antiarrhythmic drug, but it possesses electrophysiologic characteristics of all four Vaughan Williams classes. Like class I drugs, amiodarone blocks sodium channels at rapid pacing frequencies, and like class II drugs, amiodarone exerts a noncompetitive antisympathetic action. One of its main effects, with prolonged administration, is to lengthen the cardiac action potential, a class III effect. The negative chronotropic effect of amiodarone in nodal tissues is similar to the effect of class IV drugs. In addition to blocking sodium channels, amiodarone blocks myocardial potassium channels, which contributes to slowing of conduction and prolongation of refractoriness. The antisympathetic action and the block of calcium and potassium channels are responsible for the negative dromotropic effects on the sinus node and for the slowing of conduction and prolongation of refractoriness in the atrioventricular (AV) node. Its vasodilatory action can decrease cardiac workload and consequently myocardial oxygen consumption. Intravenous amiodarone administration prolongs intranodal conduction (Atrial-His, AH) and refractoriness of the atrioventricular node (ERP AVN), but has little or no effect on sinus cycle length (SCL), refractoriness of the right atrium and right ventricle (ERP RA and ERP RV), repolarization (QTc), intraventricular conduction (QRS), and infra-nodal conduction (His-ventricular, HV). A comparison of the electrophysiologic effects of intravenous amiodarone and oral amiodarone is shown in the table below. Table 6: EFFECTS OF INTRAVENOUS AND ORAL AMIODARONE ON ELECTROPHYSIOLOGIC PARAMETERS Formulation SCL QRS QTc AH HV ERP RA ERP RV ERP AVN ↔ No change Intravenous ↔ ↔ ↔ ↑ ↔ ↔ ↔ ↑ Oral ↑ ↔ ↑ ↑ ↔ ↑ ↑ ↑ At higher doses (> 10 mg/kg) of intravenous amiodarone, prolongation of the ERP RV and modest prolongation of the QRS have been seen. These differences between oral and IV administration suggest that the initial acute effects of intravenous amiodarone may be predominately focused on the AV node, causing an intranodal conduction delay and increased nodal refractoriness due to slow channel blockade (class IV activity) and noncompetitive adrenergic antagonism (class II activity).

11 DESCRIPTION Amiodarone Hydrochloride Injection, USP contains amiodarone hydrochloride, USP (C 25 H 29 I 2 NO 3 •HCl), a class III antiarrhythmic drug. Amiodarone hydrochloride is (2-butyl-3-benzo-furanyl)[4-[2-(diethylamino)ethoxy]-3,5-diiodophenyl]methanone hydrochloride. Amiodarone hydrochloride has the following structural formula: Amiodarone HCl is a white to slightly yellow crystalline powder, and is very slightly soluble in water. It has a molecular weight of 681.78 and contains 37.3% iodine by weight. Amiodarone Hydrochloride Injection, USP is a sterile clear, pale-yellow micellar solution visually free from particulates. Each milliliter of the Amiodarone Hydrochloride Injection, USP formulation contains 50 mg of amiodarone hydrochloride, 20.2 mg of benzyl alcohol, 100 mg of polysorbate 80, and water for injection. Amiodarone Hydrochloride Injection, USP is injection administration. Amiodarone Hydrochloride Injection, USP contains polysorbate 80, which is known to leach di-(2-ethylhexyl)phthalate (DEHP) from polyvinylchloride (PVC) [see Dosage and Administration (2) ] . Amiodarone Structural Formula

10 OVERDOSAGE There have been cases, some fatal, of amiodarone overdose. Effects of an inadvertent overdose of intravenous amiodarone include hypotension, cardiogenic shock, bradycardia, AV block, and hepatotoxicity. Treat hypotension and cardiogenic shock by slowing the infusion rate or with standard therapy: vasopressor drugs, positive inotropic agents, and volume expansion. Bradycardia and AV block may require temporary pacing. Monitor hepatic enzyme concentrations closely. Neither amiodarone nor DEA is dialyzable.

16 HOW SUPPLIED/ STORAGE AND HANDLING Amiodarone Hydrochloride Injection, USP is supplied as: Product Code Unit of Sale Strength Each RF601603 NDC 65219-643-03 Unit of 25 150 mg per 3 mL (50 mg per mL) NDC 65219-643-01 3 mL in a 5 mL Single Dose Vial This product contains an RFID. 601603 NDC 63323-616-03 Unit of 25 150 mg per 3 mL (50 mg per mL) NDC 63323-616-01 3 mL in a 5 mL Single Dose Vial RF601609 NDC 65219-645-09 Unit of 10 450 mg per 9 mL (50 mg per mL) NDC 65219-645-01 9 mL in a 10 mL Single Dose Vial This product contains an RFID. 601609 NDC 63323-616-09 Unit of 10 450 mg per 9 mL (50 mg per mL) NDC 63323-616-02 9 mL in a 10 mL Single Dose Vial The container closure is not made with natural rubber latex. Store at 20° to 25°C (68° to 77°F) [see USP Controlled Room Temperature]. Protect from light and excessive heat. Use carton to protect contents from light until used.