topiramate

1 INDICATIONS AND USAGE Topiramate is indicated for: Epilepsy: initial monotherapy for the treatment of partial-onset or primary generalized tonic-clonic seizures in patients 2 years of age and older ( 1.1 ); adjunctive therapy for the treatment of partial-onset seizures, primary generalized tonic-clonic seizures, or seizures associated with Lennox-Gastaut syndrome in patients 2 years of age and older ( 1.2 ) Preventive treatment of migraine in patients 12 years of age and older ( 1.3 ) 1.1 Monotherapy Epilepsy Topiramate tablets and topiramate capsules are indicated as initial monotherapy for the treatment of partial-onset or primary generalized tonic-clonic seizures in patients 2 years of age and older. 1.2 Adjunctive Therapy Epilepsy Topiramate tablets and topiramate capsules are indicated as adjunctive therapy for the treatment of partial-onset seizures, primary generalized tonic-clonic seizures, and seizures associated with Lennox-Gastaut syndrome in patients 2 years of age and older. 1.3 Migraine Topiramate tablets and topiramate capsules are indicated for the preventive treatment of migraine in patients 12 years of age and older.

2 DOSAGE AND ADMINISTRATION Topiramate initial dose, titration, and recommended maintenance dose varies by indication and age group. See Full Prescribing Information for recommended dosage, and dosing considerations in patients with renal impairment, geriatric patients, and patients undergoing hemodialysis ( 2.1 , 2.2 , 2.3 , 2.4 , 2.5 , 2.6 ) 2.1 Dosing in Monotherapy Epilepsy Adults and Pediatric Patients 10 Years of Age and Older The recommended dose for topiramate monotherapy in adults and pediatric patients 10 years of age and older is 400 mg/day in two divided doses. The dose should be achieved by titration according to the following schedule (Table 1): Table 1 Monotherapy Titration Schedule for Adults and Pediatric Patients 10 years and older Morning Dose Evening Dose Week 1 25 mg 25 mg Week 2 50 mg 50 mg Week 3 75 mg 75 mg Week 4 100 mg 100 mg Week 5 150 mg 150 mg Week 6 200 mg 200 mg Pediatric Patients 2 to 9 Years of Age Dosing in patients 2 to 9 years of age is based on weight. During the titration period, the initial dose of topiramate is 25 mg/day nightly for the first week. Based upon tolerability, the dosage can be increased to 50 mg/day (25 mg twice daily) in the second week. Dosage can be increased by 25 mg/day to 50 mg/day each subsequent week as tolerated. Titration to the minimum maintenance dose should be attempted over 5 weeks to 7 weeks of the total titration period. Based upon tolerability and clinical response, additional titration to a higher dose (up to the maximum maintenance dose) can be attempted at 25 mg/day to 50 mg/day weekly increments. The total daily dose should not exceed the maximum maintenance dose for each range of body weight ( Table 2 ). Table 2 Monotherapy Target Total Daily Maintenance Dosing for Patients 2 to 9 Years of Age * Administered in two equally divided doses Weight (kg) Total Daily Dose (mg/day)* Minimum Maintenance Dose Total Daily Dose (mg/day)* Maximum Maintenance Dose Up to 11 150 250 12 to 22 200 300 23 to 31 200 350 32 to 38 250 350 Greater than 38 250 400 2.2 Dosing in Adjunctive Therapy Epilepsy Adults (17 Years of Age and Older) The recommended total daily dose of topiramate as adjunctive therapy in adults with partial-onset seizures or Lennox-Gastaut Syndrome is 200 mg/day to 400 mg/day in two divided doses, and 400 mg/day in two divided doses as adjunctive treatment in adults with primary generalized tonic-clonic seizures. Topiramate should be initiated at 25 mg/day to 50 mg/day, followed by titration to an effective dose in increments of 25 mg/day to 50 mg/day every week. Titrating in increments of 25 mg/day every week may delay the time to reach an effective dose. Doses above 400 mg/day have not been shown to improve responses in adults with partial-onset seizures. Pediatric Patients 2 to 16 Years of Age The recommended total daily dose of topiramate as adjunctive therapy for pediatric patients 2 years to 16 years of age with partial-onset seizures, primary generalized tonic-clonic seizures, or seizures associated with Lennox-Gastaut syndrome is approximately 5 mg/kg/day to 9 mg/kg/day in two divided doses. Titration should begin at 25 mg/day (or less, based on a range of 1 mg/kg/day to 3 mg/kg/day) nightly for the first week. The dosage should then be increased at 1- or 2-week intervals by increments of 1 mg/kg/day to 3 mg/kg/day (administered in two divided doses), to achieve optimal clinical response. Dose titration should be guided by clinical outcome. The total daily dose should not exceed 400 mg/day. 2.3 Dosing for the Preventive Treatment of Migraine The recommended total daily dose of topiramate as treatment for patients 12 years of age and older for the preventive treatment of migraine is 100 mg/day administered in two divided doses (Table 3). The recommended titration rate for topiramate for the preventive treatment of migraine is as follows: Table 3 Preventive Treatment of Migraine Titration Schedule for Patients 12 Years of Age and Older Morning Dos…

5 WARNINGS AND PRECAUTIONS Acute myopia and secondary angle closure glaucoma: can lead to permanent visual loss; discontinue topiramate as soon as possible ( 5.1 ) Visual field defects: consider discontinuation of topiramate ( 5.2 ) Oligohidrosis and hyperthermia: monitor decreased sweating and increased body temperature, especially in pediatric patients ( 5.3 ) Metabolic acidosis: baseline and periodic measurement of serum bicarbonate is recommended; consider dose reduction or discontinuation of topiramate if clinically appropriate ( 5.4 ) Suicidal behavior and ideation: antiepileptic drugs increase the risk of suicidal behavior or ideation ( 5.5 ) Cognitive/neuropsychiatric adverse reactions: use caution when operating machinery including cars; depression and mood problems may occur ( 5.6 ) Fetal Toxicity: use during pregnancy can cause major congenital malformations, including but not limited to cleft lip and/or palate and being small for gestational age ( 5.7 ) Withdrawal of AEDs: withdraw topiramate gradually ( 5.8 ) Decrease in Bone Mineral Density: has been shown to decrease bone mineral density and bone mineral content in pediatric patients ( 5.9 ) Negative effects on growth (height and weight): may slow height increase and weight gain; carefully monitor children receiving prolonged therapy ( 5.10 ) Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS)/ Multiorgan Hypersensitivity, serious skin reactions (SJS or TEN), anaphylaxis and angioedema: Discontinue Topiramate if an alternative etiology cannot be established ( 5.11 , 5.12 , 5.13 ) Hyperammonemia/encephalopathy: measure ammonia if encephalopathic symptoms occur ( 5.14 ) Kidney stones: avoid use with other carbonic anhydrase inhibitors, drugs causing metabolic acidosis, or in patients on a ketogenic diet ( 5.15 ) Hypothermia has been reported with and without hyperammonemia during topiramate treatment with concomitant valproic acid use ( 5.16 ) 5.1 Acute Myopia and Secondary Angle Closure Glaucoma Syndrome A syndrome consisting of acute myopia associated with secondary angle closure glaucoma has been reported in patients receiving topiramate. Symptoms include acute onset of decreased visual acuity and/or ocular pain. Ophthalmologic findings can include some or all of the following: myopia, mydriasis, anterior chamber shallowing, ocular hyperemia (redness), choroidal detachments, retinal pigment epithelial detachments, macular striae, and increased intraocular pressure. This syndrome may be associated with supraciliary effusion resulting in anterior displacement of the lens and iris, with secondary angle closure glaucoma. Symptoms typically occur within 1 month of initiating topiramate therapy. In contrast to primary narrow angle glaucoma, which is rare under 40 years of age, secondary angle closure glaucoma associated with topiramate has been reported in pediatric patients as well as adults. The primary treatment to reverse symptoms is discontinuation of topiramate as rapidly as possible, according to the judgment of the treating physician. Other measures, in conjunction with discontinuation of topiramate, may be helpful. Elevated intraocular pressure of any etiology, if left untreated, can lead to serious sequelae including permanent vision loss. 5.2 Visual Field Defects Visual field defects (independent of elevated intraocular pressure) have been reported in clinical trials and in postmarketing experience in patients receiving topiramate. In clinical trials, most of these events were reversible after topiramate discontinuation. If visual problems occur at any time during topiramate treatment, consideration should be given to discontinuing the drug. 5.3 Oligohidrosis and Hyperthermia Oligohidrosis (decreased sweating), infrequently resulting in hospitalization, has been reported in association with topiramate use. Decreased sweating and an elevation in body temperature above normal characterized these cases. Some of the cases were reported after exposure…

4 CONTRAINDICATIONS History of hypersensitivity reaction to topiramate, topiramate, or any of the inactive ingredients of topiramate ( 4 , 5.13 ) Topiramate is contraindicated in patients with a history of hypersensitivity reaction to topiramate, topiramate, or any of the inactive ingredients of topiramate. Anaphylaxis and angioedema have occurred [see Warnings and Precautions ( 5.13 )] .

7 DRUG INTERACTIONS Contraceptives: decreased contraceptive efficacy and increased breakthrough bleeding, especially at doses greater than 200 mg/day ( 7.4 ) Monitor lithium levels if lithium is used with high-dose topiramate ( 7.7 ) 7.1 Antiepileptic Drugs Concomitant administration of phenytoin or carbamazepine with topiramate resulted in a clinically significant decrease in plasma concentrations of topiramate when compared to topiramate given alone. A dosage adjustment may be needed [see Dosage and Administration ( 2.1 ), Clinical Pharmacology ( 12.3 )]. Concomitant administration of valproic acid and topiramate has been associated with hypothermia and hyperammonemia with and without encephalopathy. Examine blood ammonia levels in patients in whom the onset of hypothermia has been reported [see Warnings and Precautions ( 5.14 , 5.16 ), Clinical Pharmacology ( 12.3 )] . 7.2 Other Carbonic Anhydrase Inhibitors Concomitant use of topiramate, a carbonic anhydrase inhibitor, with any other carbonic anhydrase inhibitor (e.g., zonisamide or acetazolamide) may increase the severity of metabolic acidosis and may also increase the risk of kidney stone formation. Therefore, patients given topiramate concomitantly with another carbonic anhydrase inhibitor should be monitored particularly closely for the appearance or worsening of metabolic acidosis [see Clinical Pharmacology ( 12.3 )]. 7.3 CNS Depressants Concomitant administration of topiramate and alcohol or other CNS depressant drugs has not been evaluated in clinical studies. Because of the potential of topiramate to cause CNS depression, as well as other cognitive and/or neuropsychiatric adverse reactions, topiramate should be used with extreme caution if used in combination with alcohol and other CNS depressants. 7.4 Contraceptives The possibility of decreased contraceptive efficacy and increased breakthrough bleeding may occur in patients taking contraceptive products with topiramate. Patients taking estrogen-containing or progestin-only contraceptives should be asked to report any change in their bleeding patterns. Contraceptive efficacy can be decreased even in the absence of breakthrough bleeding [see Clinical Pharmacology ( 12.3 )]. 7.5 Hydrochlorothiazide (HCTZ) Topiramate C max and AUC increased when HCTZ was added to topiramate. The clinical significance of this change is unknown. The addition of HCTZ to topiramate may require a decrease in the topiramate dose [see Clinical Pharmacology ( 12.3 )]. 7.6 Pioglitazone A decrease in the exposure of pioglitazone and its active metabolites were noted with the concurrent use of pioglitazone and topiramate in a clinical trial. The clinical relevance of these observations is unknown; however, when topiramate is added to pioglitazone therapy or pioglitazone is added to topiramate therapy, careful attention should be given to the routine monitoring of patients for adequate control of their diabetic disease state [see Clinical Pharmacology ( 12.3 )] . 7.7 Lithium An increase in systemic exposure of lithium following topiramate doses of up to 600 mg/day can occur. Lithium levels should be monitored when co-administered with high-dose topiramate [see Clinical Pharmacology ( 12.3 )] . 7.8 Amitriptyline Some patients may experience a large increase in amitriptyline concentration in the presence of topiramate and any adjustments in amitriptyline dose should be made according to the patient's clinical response and not on the basis of plasma levels [see Clinical Pharmacology ( 12.3 )] .

8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to topiramate during pregnancy. Patients should be encouraged to enroll in the North American Antiepileptic Drug (NAAED) Pregnancy Registry if they become pregnant. This registry is collecting information about the safety of antiepileptic drugs during pregnancy. To enroll, patients can call the toll-free number 1-888-233-2334. Information about the North American Drug Pregnancy Registry can be found at http://www.aedpregnancyregistry.org/. Risk Summary Topiramate can cause fetal harm when administered to a pregnant woman. Data from pregnancy registries indicate that infants exposed to topiramate in utero have an increased risk of major congenital malformations, including but not limited to cleft lip and/or cleft palate (oral clefts) and of being small for gestational age (SGA) [see Human Data] . SGA has been observed at all doses and appears to be dose-dependent. The prevalence of SGA is greater in infants of women who received higher doses of topiramate during pregnancy. In addition, the prevalence of SGA in infants of women who continued topiramate use until later in pregnancy is higher compared to the prevalence in infants of women who stopped topiramate use before the third trimester. In multiple animal species, topiramate produced developmental toxicity, including increased incidences of fetal malformations, in the absence of maternal toxicity at clinically relevant doses [see Animal Data] . All pregnancies have a background risk of birth defects, loss, or other adverse outcomes. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. In the U.S. general population, the estimated background risks of major birth defects and miscarriage in clinically recognized pregnancies are 2 to 4% and 15 to 20%, respectively. Clinical Considerations Fetal/Neonatal Adverse Reactions Consider the benefits and risks of topiramate when prescribing this drug to women of childbearing potential, particularly when topiramate is considered for a condition not usually associated with permanent injury or death. Because of the risk of oral clefts to the fetus, which occur in the first trimester of pregnancy, all women of childbearing potential should be informed of the potential risk to the fetus from exposure to topiramate. Women who are planning a pregnancy should be counseled regarding the relative risks and benefits of topiramate use during pregnancy, and alternative therapeutic options should be considered for these patients. Labor or Delivery Although the effect of topiramate on labor and delivery in humans has not been established, the development of topiramate-induced metabolic acidosis in the mother and/or in the fetus might affect the fetus' ability to tolerate labor. Topiramate treatment can cause metabolic acidosis [see Warnings and Precautions ( 5.4 )] . The effect of topiramate-induced metabolic acidosis has not been studied in pregnancy; however, metabolic acidosis in pregnancy (due to other causes) can cause decreased fetal growth, decreased fetal oxygenation, and fetal death, and may affect the fetus' ability to tolerate labor. Pregnant patients should be monitored for metabolic acidosis and treated as in the nonpregnant state [see Warnings and Precautions ( 5.4 )] . Newborns of mothers treated with topiramate should be monitored for metabolic acidosis because of transfer of topiramate to the fetus and possible occurrence of transient metabolic acidosis following birth. Based on limited information, topiramate has also been associated with pre-term labor and premature delivery. Data Human Data Data from pregnancy registries indicate an increased risk of major congenital malformations, including but not limited to oral clefts in infants exposed to topiramate during the first trimester of pregnancy. Other than oral clefts, no specific pattern of major …

8.3 Females and Males of Reproductive Potential Contraception Women of childbearing potential who are not planning a pregnancy should use effective contraception because of the risk of major congenital malformations, including oral clefts and the risk of infants being SGA [see Drug Interactions ( 7.4 ) and Use in Specific Populations ( 8.1 )] .

6 ADVERSE REACTIONS Epilepsy: Most common (≥10% more frequent than placebo or low-dose topiramate) adverse reactions in adult and pediatric patients were: paresthesia, anorexia, weight loss, speech disorders/related speech problems, fatigue, dizziness, somnolence, nervousness, psychomotor slowing, abnormal vision and fever ( 6.1) Migraine: Most common (≥5% more frequent than placebo) adverse reactions in adult and pediatric patients were: paresthesia, anorexia, weight loss, difficulty with memory, taste perversion, diarrhea, hypoesthesia, nausea, abdominal pain and upper respiratory tract infection ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Zydus Pharmaceuticals (USA) Inc. at 1-877-993-8779 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. The following serious adverse reactions are discussed in more detail in other sections of the labeling: Acute Myopia and Secondary Angle Closure Glaucoma [see Warnings and Precautions ( 5.1 )] Visual Field Defects [see Warnings and Precautions ( 5.2 )] Oligohidrosis and Hyperthermia [see Warnings and Precautions ( 5.3 )] Metabolic Acidosis [see Warnings and Precautions ( 5.4 )] Suicidal Behavior and Ideation [see Warnings and Precautions ( 5.5 )] Cognitive/Neuropsychiatric Adverse Reactions [see Warnings and Precautions ( 5.6 )] Decrease of Bone Mineral Density [see Warnings and Precautions ( 5.9 )] Negative Effects on Growth (Height and Weight) [see Warnings and Precautions ( 5.10 )] Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS)/Multiorgan Hypersensitivity Reactions [see Warnings and Precautions ( 5.11 )] Serious Skin Reactions [see Warnings and Precautions ( 5.12 )] Anaphylaxis and Angioedema [see Warnings and Precautions ( 5.13 )] Hyperammonemia and Encephalopathy (Without and With Concomitant Valproic Acid [VPA] Use) [see Warnings and Precautions ( 5.14 )] Kidney Stones [see Warnings and Precautions ( 5.15 )] Hypothermia with Concomitant Valproic Acid (VPA) Use [see Warnings and Precautions ( 5.16 )] The data described in the following sections were obtained using topiramate tablets. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, the incidence of adverse reactions observed in the clinical trials of a drug cannot be directly compared to the incidence of adverse reactions in the clinical trials of another drug, and may not reflect the incidence of adverse reactions observed in practice. Monotherapy Epilepsy Adults 16 Years of Age and Older The most common adverse reactions in the controlled clinical trial (Study 1) that occurred in adults in the 400 mg/day topiramate group and at an incidence higher ( ≥ 10 %) than in the 50 mg/day group were: paresthesia, weight loss and anorexia (see Table 5). Approximately 21% of the 159 adult patients in the 400 mg/day group who received topiramate as monotherapy in Study 1 discontinued therapy due to adverse reactions. The most common ( ≥ 2% more frequent than low-dose 50 mg/day topiramate) adverse reactions causing discontinuation were difficulty with memory, fatigue, asthenia, insomnia, somnolence, and paresthesia. Pediatric Patients 6 to 15 Years of Age The most common adverse reactions in the controlled clinical trial (Study 1) that occurred in pediatric patients in the 400 mg/day topiramate group and at an incidence higher ( ≥ 10%) than in the 50 mg/day group were fever and weight loss (see Table 5). Approximately 14% of the 77 pediatric patients in the 400 mg/day group who received topiramate as monotherapy in the controlled clinical trial discontinued therapy due to adverse reactions. The most common ( ≥ 2% more frequent than low-dose 50 mg/day topiramate) adverse reactions resulting in discontinuation were difficulty with concentration/attention, fever, flushing, and confusion. Table 5 presents the incidence of adverse reactions occurring in at least 3% of adult and pediatric patients treated with 400 mg/day topiramate and occurring with greater incidence than 50…