SEZABY

Phenobarbital is a barbiturate. Chemically, phenobarbital sodium is 2,4,6(1H,3H,5H)-Pyrimidinetrione, 5-ethyl-5-phenyl-, monosodium salt and has the following structural formula: C 12 H 11 N 2 NaO 3 MW 254.22 The sodium salt of phenobarbital occurs as a white, slightly bitter powder, crystalline granules or flaky crystals; it is very soluble in water, soluble in alcohol and practically insoluble in ether or chloroform. SEZABY (phenobarbital sodium) for injection, for intravenous use, is supplied as sterile white to off white lyophilized powder in a 10 mL tubular glass vial. Each single-dose vial contains 100 mg of phenobarbital sodium, USP (equivalent to 91.35 mg of phenobarbital). The pH range is 9.20-10.00. SEZABY does not contain benzyl alcohol or propylene glycol. sezaby-1

SEZABY is indicated for the treatment of neonatal seizures in term and preterm infants. SEZABY is a barbiturate indicated for the treatment of neonatal seizures in term and preterm infants.

Loading Dose: 20 mg/kg is administered by intravenous infusion over 15 minutes into a large peripheral vein. If clinically indicated, at least 15 minutes after completion of the initial loading dose, a second loading dose may be administered over the subsequent 15 minutes as 20 mg/kg for term infants or 10 mg/kg or 20 mg/kg for preterm infants. The maximum total loading dose is 40 mg/kg. (2.1) Maintenance Dosage: starting 8 to 12 hours after first loading dose: 4.5 mg/kg/day given in 2 or 3 divided doses (i.e., 1.5 mg/kg every 8 hours or 2.25 mg/kg every 12 hours) up to 5 days. (2.1). Must be reconstituted with 10 mL 0.9 % Sodium Chloride Injection, USP prior to administration. See additional preparation and administration instructions in the Full Prescribing Information. (2.3) 2.1 Recommended Dosage and Administration The recommended dosage of SEZABY in neonates consists of a loading dose(s) followed by maintenance dosage (see Table 1). Administer SEZABY by intravenous infusion (over 15 minutes) into a large peripheral vein to avoid local tissue toxicity [see Warnings and Precautions (5.9)]. SEZABY is for intravenous use only. Table 1: Recommended Dosage of SEZABY for Neonatal Seizures Loading Dose (maximum total loading dose is 40 mg/kg) First loading dose 20 mg/kg Second loading dose (If clinically indicated) 1 Preterm Infants 10 mg/kg or 20 mg/kg [see Clinical Pharmacology (12.3)] Term Infants 20 mg/kg Maintenance Dosage (total daily dose is 4.5 mg/kg/day and the total duration is up to 5 days) Initiate 8 to 12 hours after first loading dose Option 1 1.5 mg/kg every 8 hours Option 2 2.25 mg/kg every 12 hours 1 If seizures persist or recur any time 15 minutes after completion of the initial loading dose, administer a second loading dose. (Administer the second loading dose no sooner than 15 minutes after completion of the first loading dose.) 2.2 Reconstitution and Additional Administration Instructions Determine the number of vials to be reconstituted based on the patient’s weight and recommended dose. Aseptically reconstitute the lyophilized powder in the vial using 10 mL of 0.9% Sodium Chloride Injection, USP. Swirl the vial gently until contents are completely dissolved. The reconstituted solution contains 100 mg per 10 mL (10 mg/mL) of phenobarbital sodium. Inspect the vial visually for particulate matter and discoloration prior to administration (the reconstituted solution is clear, colorless, and free from visible particulate matter). Discard the reconstituted solution if it is discolored or contains foreign particles. Withdraw the appropriate volume from the reconstituted vial for intravenous infusion and administer immediately [see Dosage and Administration (2.3)] . Discard any unused portion of the reconstituted solution left in the vial [see Description (11)]. 2.3 Storage of Reconstituted Solution If the reconstituted solution is not administered immediately, place the vial back in the original carton to protect it from light and store at either room temperature at 20°C to 25°C (68°F to 77°F) for a maximum of 8 hours or in the refrigerator at 2°C to 8°C (36°F to 46°F) for a maximum of 24 hours. Discard any unused portion of the reconstituted solution after the recommended storage duration.

SEZABY is contraindicated in patients with: acute porphyrias [see Warnings and Precautions (5.8)], or a history of hypersensitivity reaction to phenobarbital or other barbiturates [see Warnings and Precautions (5.7)] Acute porphyrias (4) Hypersensitivity to phenobarbital or other barbiturates (4)

The following clinically significant adverse reactions are described elsewhere in the labeling: Risks from Concomitant Use with Opioids [see Warnings and Precautions (5.1)] Dependence and Withdrawal Reactions After Use of SEZABY for a Longer Duration Than Recommended [see Warnings and Precautions (5.2)] Abuse, Misuse, and Addiction with Unapproved Use in Adolescents and Adults [see Warnings and Precautions (5.3)] Respiratory Depression or Insufficiency [see Warnings and Precautions (5.4)] Serious Dermatologic Reactions [see Warnings and Precautions (5.5)] Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS)/Multiorgan Hypersensitivity [see Warnings and Precautions (5.6)] Hypersensitivity [see Warnings and Precautions (5.7)] Exacerbation of Porphyria [see Warnings and Precautions (5.8)] Injection Site Reactions [see Warnings and Precautions (5.9)] QT Prolongation [see Warnings and Precautions (5.10)] Embryofetal Toxicity with Unapproved Use in Adolescents and Adults [see Warnings and Precautions (5.11)] Neonatal Adverse Reactions from Unapproved Maternal Phenobarbital Use [see Warnings and Precautions (5.12)] Sedation, Respiratory Depression, and Withdrawal in Neonates Exposed to Phenobarbital Through Breast Milk [see Warnings and Precautions (5.13)] Suicidal Behavior and Ideation with Unapproved use in Adolescents and Adults [see Warnings and Precautions (5.14)] The most common adverse reactions (incidence > 5% patients overall) are abnormal respiration, sedation, feeding disorder, and hypotension. (6.1) To report SUSPECTED ADVERSE REACTIONS, contact Sun Pharmaceutical Industries, Inc. at 1-800-818-4555 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. The Study 1 was a multicenter, randomized, double-blind, active-controlled study in neonates who were experiencing seizures [see Clinical Studies (14)] . Patients were infants younger than 14 days of age with gestational ages between 36 and 44 weeks. Overall, 106 neonates (51 female and 55 male) were randomized to receive either phenobarbital (N=42) or levetiracetam (N=64) as their initial treatment. Patients received up to two 15-minute infusions of their initially assigned treatment (loading dose(s)) followed by maintenance treatment of up to 5 days. Mean durations of phenobarbital and levetiracetam treatments were 4.3 and 4 days, respectively. Table 2 summarizes the adverse reactions that occurred in 2% or more of neonates in Study 1. Incidences are displayed for neonates who received phenobarbital only and for neonates who received levetiracetam only. Because patients in Study 1 were neonates, adverse reactions that are verbally reported could not be assessed in this study. Table 2: Adverse Reactions That Occurred in At Least 2% of Neonates Overall in Study 1 by Treatment Received Phenobarbital (N = 32)* % Levetiracetam (N = 19) % Respiration abnormal 25 5 Sedation 16 5 Feeding disorder 16 5 Hypotension 16 0 Bradycardia 3 0 Hyponatremia 3 0 Sepsis 3 0 * Fifty-five neonates received both phenobarbital and levetiracetam and they had a similar adverse reaction profile as neonates who received only phenobarbital. 6.2 Postmarketing Experience The following adverse reactions associated with the use of phenobarbital in neonates were identified in the literature. 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. Cardiovascular System : Bradycardia, patent ductus arteriosus Dermatologic Reactions : Eczema Hepatic : Abnormal liver function Musculoskeletal : Hypotonia, absent deep tendon reflexes Nervous System : Impaired consciousness, neurological impairment Renal : Abnormal kidney function Respiratory System : Bronchial secretion, respiratory depression

CYP2C9, 2C19, 2E1, UGT Inhibitors: Closely monitor and decrease SEZABY dosage, if needed. (7.1) CYP3A4, 2B6, 2C, UGT Substrates: Substrate dosage adjustment may be needed. (7.1) CNS depressants: Closely monitor for sedation and respiratory depression. (7.2) Drugs that Prolong the QT Interval : Avoid concomitant use. (7.3) 7.1 Cytochrome P450- or Uridine 5’-diphospho-glucuronosyltransferase (UGT)-Based Interactions The drug interaction information in Table 3 is based upon published literature in non-neonatal populations, in vitro studies, and the mechanistic knowledge of phenobarbital metabolic pathways [see Clinical Pharmacology (12.3)] . Although the data from the published literature regarding these drug interactions are from non-neonatal populations and the magnitude of the potential drug interactions in neonates have not been characterized, this information still warrants consideration given the potential impact of these possible drug interactions on the safety and efficacy of phenobarbital and CYP2B6, 2C9, 2C19, or UGT substrates in neonates. Table 3: Drug Interactions with SEZABY Effects of Other Drugs on SEZABY CYP2C9, 2C19, 2E1, Uridine 5'-diphospho-glucuronosyltransferases ( UGT) Inhibitors or Inducers Prevention or Management Closely monitor for adverse reactions (e.g., over sedation, prolonged QTc interval, etc.) when used concomitantly with inhibitors of these enzymes and reduced efficacy (e.g., breakthrough seizure) when used with inducers of these enzymes. Consider titration of the SEZABY maintenance dosage accordingly if concomitant use is unavoidable. Clinical Effect(s) Phenobarbital is a substrate of CYP2C9, CYP2C19, CYP2E1, and UGTs [see Clinical Pharmacology (12.3)] . It is likely that concomitant use will result in an increase in phenobarbital exposure when used with these inhibitors and a reduction when used with these inducers, which may increase the risk of SEZABY adverse reactions or reduce efficacy, respectively when concomitant use in neonates. Effects of Other Drugs on Sezaby CYP3A, 2B6, 2C(s), UGTs Substrates Prevention or Management Closely monitor neonates when SEZABY is used concurrently with substrates of these enzymes and consider increasing the dosage of the substrate accordingly, unless otherwise advised in its Prescribing Information, if concomitant use is unavoidable. Clinical Effect(s) Phenobarbital is an inducer of CYP3A, CYP2B6, CYP2C(s), and UGT(s) [see Clinical Pharmacology (12.3)] . It is likely that concomitant use in neonates will result in a decrease in the exposure of these substrates, which may reduce efficacy. 7.2 CNS Depressants Closely monitor for signs of sedation and respiratory depression with concomitant use of SEZABY with other CNS depressants, including opioids [see Warnings and Precautions (5.1)] . Phenobarbital may cause sedation and respiratory depression [see Warnings and Precautions (5.4) and Adverse Reactions (6.1)] . Other products that may also cause these adverse reactions may have additive pharmacologic effect and may increase the risk of sedation and respiratory depression. 7.3 Drugs that Prolong QT Interval SEZABY may prolong the QT interval [see Warnings and Precautions (5.10) and Clinical Pharmacology (12.2)] . Other products that may also prolong the QTc interval may have additive effects, and products that may increase concentrations of phenobarbital [see Drug Interactions (7.1)] may increase the QT prolongation risk; therefore, avoid concomitant use of SEZABY and these products. If concomitant use of a product that also prolongs the QTc interval or that increases SEZABY concentrations is unavoidable, monitor patients for increased risk of QTc interval prolongation.