Oxcarbazepine

1 INDICATIONS AND USAGE Oxcarbazepine oral suspension is indicated for use as monotherapy or adjunctive therapy in the treatment of partial-onset seizures in adults and as monotherapy in the treatment of partial-onset seizures in pediatric patients aged 4 years and above, and as adjunctive therapy in pediatric patients aged 2 years and above with partial-onset seizures. Oxcarbazepine oral suspension is indicated for: • Adults: Monotherapy or adjunctive therapy in the treatment of partial-onset seizures • Pediatrics: -Monotherapy in the treatment of partial-onset seizures in children 4 to 16 years -Adjunctive therapy in the treatment of partial-onset seizures in children 2 to 16 years ( 1 )

12.1 Mechanism of Action The pharmacological activity of oxcarbazepine is primarily exerted through the 10-monohydroxy metabolite (MHD) of oxcarbazepine [see Clinical Pharmacology (12.3) ]. The precise mechanism by which oxcarbazepine and MHD exert their anti-seizure effect is unknown; however, in vitro electrophysiological studies indicate that they produce blockade of voltage-sensitive sodium channels, resulting in stabilization of hyperexcited neural membranes, inhibition of repetitive neuronal firing, and diminution of propagation of synaptic impulses. These actions are thought to be important in the prevention of seizure spread in the intact brain. In addition, increased potassium conductance and modulation of high-voltage activated calcium channels may contribute to the anticonvulsant effects of the drug. No significant interactions of oxcarbazepine or MHD with brain neurotransmitter or modulator receptor sites have been demonstrated.

2 DOSAGE AND ADMINISTRATION Adults : Initiate with a dose of 600 mg/day, given twice a day • Adjunctive Therapy: Maximum increment of 600 mg/day at approximately weekly intervals. The recommended daily dose is 1,200 mg/day ( 2.1 ) • Conversion to Monotherapy: Withdrawal concomitant over 3 to 6 weeks; reach maximum dose of oxcarbazepine oral suspension in 2 to 4 weeks with increments of 600 mg/day at weekly intervals to a recommended daily dose of 2,400 mg/day ( 2.2 ) • Initiation of Monotherapy: Increments of 300 mg/day every third day to a dose of 1,200 mg/day ( 2.3 ) • Initiate at one-half the usual starting dose and increase slowly in patients with a creatinine clearance < 30 mL/min ( 2.7 ) Pediatrics : Initiation with 8 to 10 mg/kg/day, given twice a day. For patients aged 2 to < 4 years and under 20 kg, a starting dose of 16 to 20 mg/kg/day may be considered. Recommended daily dose is dependent upon patient weight. • Adjunctive Patients (Aged 2 to 16 Years): For patients aged 4 to 16 years, target maintenance dose should be achieved over 2 weeks ( 2.4 ). For patients aged 2 to < 4 years, maximum maintenance dose should be achieved over 2 to 4 weeks and should not exceed 60mg/kg/day ( 2.4 ) • Conversion to Monotherapy for Patients (Aged 4 to 16 Years): Maximum increment of 10 mg/kg/day at weekly intervals, concomitant antiepileptic drugs (AEDs) can be completely withdrawn over 3 to 6 weeks ( 2.5) • Initiation of Monotherapy for Patients (Aged 4 to 16 Years): Increments of 5 mg/kg/day every third day ( 2.6 ) 2.1 Adjunctive Therapy for Adults Initiate oxcarbazepine oral suspension with a dose of 600 mg/day, given twice a day. If clinically indicated, the dose may be increased by a maximum of 600 mg/day at approximately weekly intervals; the maximum recommended daily dose is 1,200 mg/day. Daily doses above 1,200 mg/day show somewhat greater effectiveness in controlled trials, but most patients were not able to tolerate the 2,400 mg/day dose, primarily because of central nervous (CNS) effects. Dosage adjustment is recommended with concomitant use of strong CYP3A4 enzyme inducers or UDP-glucuronosyltransferases (UGT) inducers, which include certain antiepileptic drugs (AEDs) [see Drug Interactions (7.1, 7.2) ]. 2.2 Conversion to Monotherapy for Adults Patients receiving concomitant AEDs may be converted to monotherapy by initiating treatment with oxcarbazepine oral suspension at 600 mg/day (given in a twice a day regimen) while simultaneously initiating the reduction of the dose of the concomitant AEDs. The concomitant AEDs should be completely withdrawn over 3 to 6 weeks, while the maximum dose of oxcarbazepine oral suspension should be reached in about 2 to 4 weeks. Oxcarbazepine oral suspension may be increased as clinically indicated by a maximum increment of 600 mg/day at approximately weekly intervals to achieve the maximum recommended daily dose of 2,400 mg/day. A daily dose of 1,200 mg/day has been shown in one study to be effective in patients in whom monotherapy has been initiated with oxcarbazepine oral suspension. Patients should be observed closely during this transition phase. 2.3 Initiation of Monotherapy for Adults Patients not currently being treated with AEDs may have monotherapy initiated with oxcarbazepine oral suspension. In these patients, initiate oxcarbazepine oral suspension at a dose of 600 mg/day (given twice a day); the dose should be increased by 300 mg/day every third day to a dose of 1,200 mg/day. Controlled trials in these patients examined the effectiveness of a 1,200 mg/day dose; a dose of 2,400 mg/day has been shown to be effective in patients converted from other AEDs to oxcarbazepine oral suspension monotherapy (see above). 2.4 Adjunctive Therapy for Pediatric Patients (Aged 2 to 16 Years) In pediatric patients aged 4 to 16 years, initiate oxcarbazepine oral suspension at a daily dose of 8 to 10 mg/kg generally not to exceed 600 mg/day, given twice a day. The target maintenance dose of oxcar

6 ADVERSE REACTIONS The following serious adverse reactions are described below and elsewhere in the labeling: • Hyponatremia [see Warnings and Precautions (5.1) ] • Anaphylactic Reactions and Angioedema [see Warnings and Precautions (5.2) ] • Cross Hypersensitivity Reaction to Carbamazepine [see Warnings and Precautions (5.3) ] • Serious Dermatological Reactions [see Warnings and Precautions (5.4) ] • Suicidal Behavior and Ideation [see Warnings and Precautions (5.5) ] • Cognitive/Neuropsychiatric Adverse Reactions [see Warnings and Precautions (5.7) ] • Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS)/Multi-Organ Hypersensitivity [see Warnings and Precautions (5.8) ] • Hematologic Events [see Warnings and Precautions (5.9) ] The most common (≥ 10% more than placebo for adjunctive or low dose for monotherapy) adverse reactions in adults and pediatrics were: dizziness, somnolence, diplopia, fatigue, nausea, vomiting, ataxia, abnormal vision, headache, nystagmus, tremor, and abnormal gait ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Novadoz Pharmaceuticals LLC at 1-855-668-2369 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. Most Common Adverse Reactions in All Clinical Studies Adjunctive Therapy/Monotherapy in Adults Previously Treated With Other AEDs The most common (≥ 10% more than placebo for adjunctive or low dose for monotherapy) adverse reactions with oxcarbazepine: dizziness, somnolence, diplopia, fatigue, nausea, vomiting, ataxia, abnormal vision, headache, nystagmus tremor, and abnormal gait. Approximately 23% of these 1,537 adult patients discontinued treatment because of an adverse reaction. The adverse reactions most commonly associated with discontinuation were: dizziness (6.4%), diplopia (5.9%), ataxia (5.2%), vomiting (5.1%), nausea (4.9%), somnolence (3.8%), headache (2.9%), fatigue (2.1%), abnormal vision (2.1%), tremor (1.8%), abnormal gait (1.7%), rash (1.4%), and hyponatremia (1%). Monotherapy in Adults Not Previously Treated With Other AEDs The most common (≥ 5%) adverse reactions with oxcarbazepine in these patients were similar to those in previously treated patients. Approximately 9% of these 295 adult patients discontinued treatment because of an adverse reaction. The adverse reactions most commonly associated with discontinuation were: dizziness (1.7%), nausea (1.7%), rash (1.7%), and headache (1.4%). Adjunctive Therapy/Monotherapy in Pediatric Patients 4 Years Old and Above Previously Treated With Other AEDs The most common (≥ 5%) adverse reactions with oxcarbazepine in these patients were similar to those seen in adults. Approximately 11% of these 456 pediatric patients discontinued treatment because of an adverse reaction. The adverse reactions most commonly associated with discontinuation were: somnolence (2.4%), vomiting (2%), ataxia (1.8%), diplopia (1.3%), dizziness (1.3%), fatigue (1.1%), and nystagmus (1.1%). Monotherapy in Pediatric Patients 4 Years Old and Above Not Previously Treated With Other AEDs The most common (≥ 5%) adverse reactions with oxcarbazepine in these patients were similar to those in adults. Approximately 9.2% of 152 pediatric patients discontinued treatment because of an adverse reaction. The adverse reactions most commonly associated (≥ 1%) with discontinuation were rash (5.3%) and maculopapular rash (1.3%). Adjunctive Therapy/Monotherapy in Pediatric Patients 1 Month to < 4 Years Old Previously Treated or Not Previously Treated with Other AEDs: The most common (≥ 5%) adverse reactions with oxcarbazepine in these patients were similar to those seen in older children and adults, except for infections and infestations which were more frequently seen in these

5 WARNINGS AND PRECAUTIONS • Hyponatremia: Monitor serum sodium levels ( 5.1 ) • Cross Hypersensitivity Reaction to Carbamazepine: Discontinue immediately if hypersensitivity occurs ( 5.3 ) • Serious Dermatological Reactions: If occurs, consider discontinuation ( 5.4 ) • Suicidal Behavior and Ideation: Monitor for suicidal thoughts/behavior ( 5.5 ) • Withdrawal of AEDs: Withdraw oxcarbazepine gradually ( 5.6 ) • Cognitive/Neuropsychiatric Adverse Reactions: May cause cognitive dysfunction, somnolence, and coordination abnormalities. Use caution when operating machinery ( 5.7) • Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS)/Multi-Organ Hypersensitivity: Monitor and discontinue if another cause cannot be established ( 5.8 ) • Hematologic Events: Consider discontinuing ( 5.9 ) • Seizure Control During Pregnancy: Active metabolite may decrease ( 5.10 ) • Risk of Seizure Aggravation: Discontinue if occurs ( 5.11 ) 5.1 Hyponatremia Clinically significant hyponatremia (sodium < 125 mmol/L) can develop during oxcarbazepine use. In the 14 controlled epilepsy studies, 2.5% of oxcarbazepine-treated patients (38/1,524) had a sodium of less than 125 mmol/L at some point during treatment, compared to no such patients assigned placebo or active control (carbamazepine and phenobarbital for adjunctive and monotherapy substitution studies, and phenytoin and valproate for the monotherapy initiation studies). Clinically significant hyponatremia generally occurred during the first 3 months of treatment with oxcarbazepine, although there were patients who first developed a serum sodium < 125 mmol/L more than 1 year after initiation of therapy. Most patients who developed hyponatremia were asymptomatic, but patients in the clinical trials were frequently monitored and some had their oxcarbazepine dose reduced, discontinued, or had their fluid intake restricted for hyponatremia. Whether or not these maneuvers prevented the occurrence of more severe events is unknown. Cases of symptomatic hyponatremia and syndrome of inappropriate antidiuretic hormone secretion (SIADH) have been reported during postmarketing use. In clinical trials, patients whose treatment with oxcarbazepine was discontinued due to hyponatremia generally experienced normalization of serum sodium within a few days without additional treatment. Measurement of serum sodium levels should be considered for patients during maintenance treatment with oxcarbazepine, particularly if the patient is receiving other medications known to decrease serum sodium levels (e.g., drugs associated with inappropriate ADH secretion), or if symptoms possibly indicating hyponatremia develop (e.g., nausea, malaise, headache, lethargy, confusion, obtundation, or increase in seizure frequency or severity). 5.2 Anaphylactic Reactions and Angioedema Rare cases of anaphylaxis and angioedema involving the larynx, glottis, lips and eyelids have been reported in patients after taking the first or subsequent doses of oxcarbazepine. Angioedema associated with laryngeal edema can be fatal. If a patient develops any of these reactions after treatment with oxcarbazepine, the drug should be discontinued and an alternative treatment started. These patients should not be rechallenged with the drug [see Warnings and Precautions (5.3) ]. 5.3 Cross Hypersensitivity Reaction to Carbamazepine Approximately 25% to 30% of patients who have had hypersensitivity reactions to carbamazepine will experience hypersensitivity reactions with oxcarbazepine. For this reason, patients should be specifically questioned about any prior experience with carbamazepine, and patients with a history of hypersensitivity reactions to carbamazepine should ordinarily be treated with oxcarbazepine only if the potential benefit justifies the potential risk. If signs or symptoms of hypersensitivity develop, oxcarbazepine should be discontinued immediately [see Warnings and Precautions (5.2, 5.8) ]. 5.4 Serious Dermatological Reactions Seriou

4 CONTRAINDICATIONS Oxcarbazepine oral suspension is contraindicated in patients with a known hypersensitivity to oxcarbazepine or to any of its components, or to eslicarbazepine acetate [see Warnings and Precautions (5.2, 5.3 )]. Known hypersensitivity to oxcarbazepine or to any of its components, or to eslicarbazepine acetate ( 4, 5.2 )

10 OVERDOSAGE 10.1 Human Overdose Experience Isolated cases of overdose with oxcarbazepine have been reported. The maximum dose taken was approximately 48,000 mg. All patients recovered with symptomatic treatment. Nausea, vomiting, somnolence, aggression, agitation, hypotension, and tremor each occurred in more than one patient. Coma, confusional state, convulsion, dyscoordination, depressed level of consciousness, diplopia, dizziness, dyskinesia, dyspnea, QT prolongation, headache, miosis, nystagmus, overdose, decreased urine output, and blurred vision also occurred. 10.2 Treatment and Management There is no specific antidote. Symptomatic and supportive treatment should be administered as appropriate. Removal of the drug by gastric lavage and/or inactivation by administering activated charcoal should be considered.