24 HR topiramate 200 MG Extended Release Oral Capsule [Trokendi]

INDICATIONS AND USAGE Topiramate extended-release capsules are indicated for: Epilepsy: initial monotherapy for the treatment of partial-onset or primary generalized tonic-clonic seizures in patients 6 years of age and older ( 1.1) ; adjunctive therapy for the treatment of partial-onset, primary generalized tonic-clonic seizures, or seizures associated with Lennox-Gastaut syndrome (LGS) in patients 6 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 extended-release capsules are indicated as initial monotherapy for the treatment of partial-onset or primary generalized tonic-clonic seizures in patients 6 years of age and older [see Clinical Studies (14.2) ] . 1.2 Adjunctive Therapy Epilepsy Topiramate extended-release 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 6 years of age and older [ see Clinical Studies (14.3) ] . 1.3 Migraine Topiramate extended-release capsules are indicated for the preventive treatment of migraine in patients 12 years of age and older [see Clinical Studies (14.4) ] . 1.1 Monotherapy Epilepsy Topiramate extended-release capsules are indicated as initial monotherapy for the treatment of partial-onset or primary generalized tonic-clonic seizures in patients 6 years of age and older [see Clinical Studies (14.2) ] . 1.2 Adjunctive Therapy Epilepsy Topiramate extended-release 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 6 years of age and older [ see Clinical Studies (14.3) ] . 1.3 Migraine Topiramate extended-release capsules are indicated for the preventive treatment of migraine in patients 12 years of age and older [see Clinical Studies (14.4) ] .

DOSAGE AND ADMINISTRATION Topiramate extended-release capsules 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 ) Swallow capsule whole and intact. Do not sprinkle on food, chew, or crush (2.7 ) 2.1 Dosing in Monotherapy Epilepsy Adults and Pediatric Patients 10 Years of Age and Older with Partial Onset or Primary Generalized Tonic-Clonic Seizures The recommended dose for topiramate extended-release capsules monotherapy in adults and in pediatric patients 10 years of age and older is 400 mg orally once daily. Titrate topiramate extended-release capsules according to the following schedule: Week 1: 50 mg once daily Week 2: 100 mg once daily Week 3: 150 mg once daily Week 4: 200 mg once daily Week 5: 300 mg once daily Week 6: 400 mg once daily Pediatric Patients Ages 6 to 9 Years of Age Dosing in patients 6 to 9 years of age is based on weight. During the titration period, the initial dose of topiramate extended-release capsules is 25 mg/day nightly for the first week. Based upon tolerability, the dosage can be increased to 50 mg/day 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 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 (see Table 1). Table 1: Monotherapy Target Total Daily Maintenance Dosing for Patients 6 to 9 Years of Age 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 extended-release capsules as adjunctive therapy in adults with partial-onset seizures or Lennox-Gastaut Syndrome is 200 mg to 400 mg orally once daily and with primary generalized tonic-clonic seizures is 400 mg orally once daily. Initiate therapy at 25 mg to 50 mg once daily followed by titration to an effective dose in increments of 25 mg to 50 mg 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 6 to 16 Years of Age The recommended total daily dose of topiramate extended-release capsules as adjunctive therapy for patients 6 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 to 9 mg/kg orally once daily. Begin titration at 25 mg once daily (or less, based on a range of 1 mg/kg/day to 3 mg/kg/day) given nightly for the first week. Subsequently, increase the dosage at 1- or 2-week intervals by increments of 1 mg/kg/day to 3 mg/kg/day 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 extended-release capsules as treatment for the preventive treatment of migraine in patients 12 years of age and older is 100 mg once daily. Titrate topiramate extended-release capsules for the preventive treatment of migraine according to the following schedule: Week 1: 25 mg once daily Week 2: 50 mg once daily Week 3: 75 mg once daily Week 4: 100 mg once daily Dose and titration rate should be guided by clinical outcome. If required, longer intervals between dose adjustments can be used. 2.4 Administration With Alcohol Alcohol use should be completely avoided within 6 hours prior to and 6 hours after topiramate extended-release capsules administration [see Warnings and Precautions ( 5. 5) ] . 2.5 Dose Modifications in Patients With Renal Impairment In patients with renal impairment (creatinine clearance less than 70 mL/min/1.73 m 2 ), one-half of the usual adult dose of topiramate extended-release capsules are recommended [see Use in Specific Populations ( 8.5 , 8.6 ) , Clinical Pharmacology ( 12.3) ] . 2.6 Dosage Modifications in Patients Undergoing Hemodialysis To avoid rapid drops in topiramate plasma concentration during hemodialysis, a supplemental dose of topiramate extended-release capsules may be required. The actual adjustment should take into account 1) the duration of dialysis period, 2) the clearance rate of the dialysis system being used, and 3) the effective renal clearance of topiramate in the patient being dialyzed [see Use in Specific Populations ( 8.7 ), Clinical Pharmacology ( 12.3) ] . 2.7 Administration Instructions Topiramate extended-release capsules can be taken without regard to meals. Swallow capsule whole and intact. Do not sprinkle on food, chew, or crush. 2.1 Dosing in Monotherapy Epilepsy Adults and Pediatric Patients 10 Years of Age and Older with Partial Onset or Primary Generalized Tonic-Clonic Seizures The recommended dose for topiramate extended-release capsules monotherapy in adults and in pediatric patients 10 years of age and older is 400 mg orally once daily. Titrate topiramate extended-release capsules according to the following schedule: Week 1: 50 mg once daily Week 2: 100 mg once daily Week 3: 150 mg once daily Week 4: 200 mg once daily Week 5: 300 mg once daily Week 6: 400 mg once daily Pediatric Patients Ages 6 to 9 Years of Age Dosing in patients 6 to 9 years of age is based on weight. During the titration period, the initial dose of topiramate extended-release capsules is 25 mg/day nightly for the first week. Based upon tolerability, the dosage can be increased to 50 mg/day 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 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 (see Table 1). Table 1: Monotherapy Target Total Daily Maintenance Dosing for Patients 6 to 9 Years of Age 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 extended-release capsules as adjunctive therapy in adults with partial-onset seizures or Lennox-Gastaut Syndrome is 200 mg to 400 mg orally once daily and with primary generalized tonic-clonic seizures is 400 mg orally once daily. Initiate therapy at 25 mg to 50 mg once daily followed by titration to an effective dose in increments of 25 mg to 50 mg 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 6 to 16 Years of Age The recommended total daily dose of topiramate extended-release capsules as adjunctive therapy for patients 6 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/

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) Serious skin reactions: If SJS or TEN is suspected, discontinue topiramate (5.11) Hyperammonemia/encephalopathy: measure ammonia if encephalopathic symptoms occur (5.12) Kidney stones: avoid use with other carbonic anhydrase inhibitors, drugs causing metabolic acidosis, or in patients on a ketogenic diet (5.13) Hypothermia has been reported with and without hyperammonemia during topiramate treatment with concomitant valproic acid use (5.14) 5.1 Acute Myopia and Secondary Angle Closure Glaucoma Syndrome A s y nd rome 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 to elevated environmental temperatures. The majority of the reports have been in pediatric patients. Patients (especially pediatric patients) treated with topiramate should be monitored closely for evidence of decreased sweating and increased body temperature, especially in hot weather. Caution should be used when topiramate is given with other drugs that predispose patients to heat-related disorders; these drugs include, but are not limited to, other carbonic anhydrase inhibitors and drugs with anticholinergic activity. 5.4 Metabolic Acidosis Topiramate can cause hyperchloremic, non-anion gap, metabolic acidosis (i.e., decreased serum bicarbonate below the normal reference range in the absence of chronic respiratory alkalosis). This metabolic acidosis is caused by renal bicarbonate loss due to carbonic anhydrase inhibition by topiramate. Topiramate-induced metabolic acidosis can occur at any time during treatment. Bicarbonate decrements are usually mild-moderate (average decrease of 4 mEq/L at daily doses of 400 mg in adults and at approximately 6 mg/kg/day in pediatric patients); rarely, patients can experience severe decrements to values below 10 mEq/L. Conditions or therapies that predispose patients to acidosis (such as renal disease, severe respiratory disorders, status epilepticus, diarrhea, ketogenic diet, or specific drugs) may be additive to the bicarbonate lowering effects of topiramate. Metabolic acidosis was commonly observed in adult and pediatric patients treated with topiramate in clinical trials. The incidence of decreased serum bicarbonate in pediatric trials, for adjunctive treatment of Lennox-Gastaut syndrome or refractory partial-onset seizures was as high as 67% for topiramate (at approximately 6 mg/kg/day), and 10% for placebo. The incidence of a markedly abnormally low serum bicarbonate (i.e., absolute value < 17 mEq/L and >5 mEq/L decrease from pretreatment) in these trials was up to 11%, compared to < 2% for placebo. Manifestations of acute or chronic metabolic acidosis may include hyperventilation, nonspecific symptoms such as fatigue and anorexia, or more severe sequelae including cardiac arrhythmias or stupor. Chronic, untreated metabolic acidosis may increase the risk for nephrolithiasis or nephrocalcinosis, and may also result in osteomalacia (referred to as rickets in pediatric patients) and/or osteoporosis with an increased risk for fractures [see Warnings and Precautions (5.9, 5.13)] . A one-year, active-controlled study of pediatric patients treated with topiramate demonstrated that topiramate decreased lumbar spine bone mineral density and that this lumbar spine bone mineral density decrease was correlated (using change from baseline for lumbar spine Z score at final visit versus lowest post-treatment serum bicarbonate) with decreased serum bicarbonate, a reflection of metabolic acidosis [see Warnings and Precautions (5.9), Use in Specific Populations (8.4)] . Chronic metabolic acidosis in pediatric patients may also reduce growth rates, which may decrease the maximal height achieved. Long-term, open-label treatment of pediatric patients 1 to 24 months old with intractable partial epilepsy, for up to 1 year, showed reductions from baseline in length, weight, and head circumference compared to age and sex-matched normative data, although these patients with epilepsy are likely to have different growth rates than normal 1 to 24 month old pediatrics. Reductions in length and weight were correlated to the degree of acidosis [see Use in Specific Populations (8.4)] . Topiramate treatment that causes metabolic acidosis during pregnancy can possibly produce adverse effects on the fetus and might also cause metabolic acidosis in the neonate from possible transfer of topiramate to the fetus [see Warnings and Precautions (5.7), Use in Specific Populations (8.1)] . Measurement of Serum Bicarbonate in Epilepsy and Migraine Patients Measurement of baseline and periodic serum bicarbonate during topiramate treatment is recommended. If metabolic acidosis develops and persists, consideration should be given to reducing the dose or discontinuing topiramate (using dose tapering). If the decision is m

CONTRAINDICATIONS Phentermine and topiramate extended-release capsules are contraindicated in patients: Who are pregnant [see Warnings and Precautions ( 5.1 ) and Use in Specific Populations ( 8.1 )] With glaucoma [see Warnings and Precautions ( 5.3 )] With hyperthyroidism Taking or within 14 days of stopping a monoamine oxidase inhibitors [see Drug Interactions ( 7 )] With known hypersensitivity to phentermine, topiramate or any of the excipients in phentermine and topiramate extended-release capsules, or idiosyncrasy to the sympathomimetic amines. Anaphylaxis and angioedema have occurred with topiramate [see Warnings and Precautions (5.15)] . Pregnancy ( 4 ) Glaucoma ( 4 ) Hyperthyroidism ( 4 ) Taking or within 14 days of stopping monoamine oxidase inhibitors ( 4 ) Known hypersensitivity to any component of phentermine and topiramate extended-release capsules or idiosyncrasy to sympathomimetic amines ( 4 )

Mechanism of Action The precise mechanisms by which topiramate exerts its anticonvulsant and preventive migraine effects are unknown; however, preclinical studies have revealed four properties that may contribute to topiramate's efficacy for epilepsy and the preventive treatment of migraine. Electrophysiological and biochemical evidence suggests that topiramate, at pharmacologically relevant concentrations, blocks voltage-dependent sodium channels, augments the activity of the neurotransmitter gamma-aminobutyrate at some subtypes of the GABA-A receptor, antagonizes the AMPA/kainate subtype of the glutamate receptor, and inhibits the carbonic anhydrase enzyme, particularly isozymes II and IV. 12.2 Pharmacodynamics Topiramate has anticonvulsant activity in rat and mouse maximal electroshock seizure (MES) tests. Topiramate is only weakly effective in blocking clonic seizures induced by the GABAA receptor antagonist, pentylenetetrazole. Topiramate is also effective in rodent models of epilepsy, which include tonic and absence-like seizures in the spontaneous epileptic rat (SER) and tonic and clonic seizures induced in rats by kindling of the amygdala or by global ischemia. Changes (increases and decreases) from baseline in vital signs (systolic blood pressure-SBP, diastolic blood pressure-DBP, pulse) occurred more frequently in pediatric patients (6 to 17 years) treated with various daily doses of topiramate (50 mg, 100 mg, 200 mg, 2 to 3 mg/kg) than in patients treated with placebo in controlled trials for the preventive treatment of migraine. The most notable changes were SBP <90 mm Hg, DBP <50 mm Hg, SBP or DBP increases or decreases ≥20 mm Hg, and pulse increases or decreases ≥30 beats per minute. These changes were often dose-related, and were most frequently associated with the greatest treatment difference at the 200 mg dose level. Systematic collection of orthostatic vital signs has not been conducted. The clinical significance of these various changes in vital signs has not been clearly established. 12.3 Pharmacokinetics Absorption of topiramate is rapid, with peak plasma concentrations occurring at approximately 2 hours following a 400 mg oral dose. The relative bioavailability of topiramate from the tablet formulation is about 80% compared to a solution. The bioavailability of topiramate is not affected by food. The pharmacokinetics of topiramate are linear with dose proportional increases in plasma concentration over the dose range studied (200 to 800 mg/day). The mean plasma elimination half-life is 21 hours after single or multiple doses. Steady-state is thus reached in about 4 days in patients with normal renal function. Topiramate is 15% to 41% bound to human plasma proteins over the blood concentration range of 0.5 to 250 μg/mL. The fraction bound decreased as blood concentration increased. Carbamazepine and phenytoin do not alter the binding of topiramate. Sodium valproate, at 500 μg/mL (a concentration 5 to 10 times higher than considered therapeutic for valproate) decreased the protein binding of topiramate from 23% to 13%. Topiramate does not influence the binding of sodium valproate. Metabolism and Excretion Topiramate is not extensively metabolized and is primarily eliminated unchanged in the urine (approximately 70% of an administered dose). Six metabolites have been identified in humans, none of which constitutes more than 5% of an administered dose. The metabolites are formed via hydroxylation, hydrolysis, and glucuronidation. There is evidence of renal tubular reabsorption of topiramate. In rats, given probenecid to inhibit tubular reabsorption, along with topiramate, a significant increase in renal clearance of topiramate was observed. This interaction has not been evaluated in humans. Overall, oral plasma clearance (CL/F) is approximately 20 to 30 mL/min in adults following oral administration. Specific Populations Renal Impairment The clearance of topiramate was reduced by 42% in subjects with moderate renal impairment (creatinine clearance 30 to 69 mL/min/1.73 m2) and by 54% in subjects with severe renal impairment (creatinine clearance <30 mL/min/1.73 m2) compared to subjects with normal renal function (creatinine clearance >70 mL/min/1.73 m2) [see Dosage and Administration (2.4) and (2.5)]. Hemodialysis Topiramate is cleared by hemodialysis. Using a high-efficiency, counterflow, single pass-dialysate hemodialysis procedure, topiramate dialysis clearance was 120 mL/min with blood flow through the dialyzer at 400 mL/min. This high clearance (compared to 20 to 30 mL/min total oral clearance in healthy adults) will remove a clinically significant amount of topiramate from the patient over the hemodialysis treatment period [see Dosage and Administration (2.6), Use in Specific Populations (8.7)]. Hepatic Impairment Plasma clearance of topiramate decreased a mean of 26% in patients with moderate to severe hepatic impairment. Age, Gender, and Race The pharmacokinetics of topiramate in elderly subjects (65 to 85 years of age, N=16) were evaluated in a controlled clinical study. The elderly subject population had reduced renal function (creatinine clearance [-20%]) compared to young adults. Following a single oral 100 mg dose, maximum plasma concentration for elderly and young adults was achieved at approximately 1 to 2 hours. Reflecting the primary renal elimination of topiramate, topiramate plasma and renal clearance were reduced 21% and 19%, respectively, in elderly subjects, compared to young adults. Similarly, topiramate half-life was longer (13%) in the elderly. Reduced topiramate clearance resulted in slightly higher maximum plasma concentration (23%) and AUC (25%) in elderly subjects than observed in young adults. Topiramate clearance is decreased in the elderly only to the extent that renal function is reduced [see Dosage and Administration (2.4) and Use in Specific Populations (8.5)]. Clearance of topiramate in adults was not affected by gender or race. Pediatric Pharmacokinetics Pharmacokinetics of topiramate were evaluated in patients age 2 to <16 years. Patients received either no or a combination of other antiepileptic drugs. A population pharmacokinetic model was developed on the basis of pharmacokinetic data from relevant topiramate clinical studies. This dataset contained data from 1217 subjects including 258 pediatric patients age 2 to <16 years (95 pediatric patients <10 years of age). Pediatric patients on adjunctive treatment exhibited a higher oral clearance (L/h) of topiramate compared to patients on monotherapy, presumably because of increased clearance from concomitant enzyme-inducing antiepileptic drugs. In comparison, topiramate clearance per kg is greater in pediatric patients than in adults and in young pediatric patients (down to 2 years) than in older pediatric patients. Consequently, the plasma drug concentration for the same mg/kg/day dose would be lower in pediatric patients compared to adults and also in younger pediatric patients compared to older pediatric patients. Clearance was independent of dose. As in adults, hepatic enzyme-inducing antiepileptic drugs decrease the steady state plasma concentrations of topiramate. Drug Interactions In vitro studies indicate that topiramate does not inhibit CYP1A2, CYP2A6, CYP2B6, CYP2C9, CYP2D6, CYP2E1, or CYP3A4/5 isozymes. In vitro studies indicate that topiramate is a mild inhibitor of CYP2C19 and a mild inducer of CYP3A4. Antiepileptic Drugs Potential interactions between topiramate and standard AEDs were assessed in controlled clinical pharmacokinetic studies in patients with epilepsy. The effects of these interactions on mean plasma AUCs are summarized in Table 11. In Table 11, the second column (AED concentration) describes what happens to the concentration of the co-administered AED listed in the first column when topiramate is added. The third column (topiramate concentration) describes how the co-administration of a drug listed in the first colu