Clobazam

Clobazam tablet is indicated for the adjunctive treatment of seizures associated with Lennox-Gastaut syndrome (LGS) in patients 2 years of age or older. Clobazam tablet is a benzodiazepine indicated for adjunctive treatment of seizures associated with Lennox-Gastaut syndrome (LGS) in patients 2 years of age or older

2 DOSAGE AND ADMINISTRATION • For doses above 5 mg/day administer in two divided doses • Patients ≤30 kg body weight: Initiate at 5 mg daily and titrate as tolerated up to 20 mg daily • Patients >30 kg body weight: Initiate at 10 mg daily and titrate as tolerated up to 40 mg daily • Dosage adjustment needed in following groups: o Geriatric patients ( 2.4 , 8.5 ) o Known CYP2C19 poor metabolizers o Mild or moderate hepatic impairment; no information for severe hepatic impairment ( 2.7 , 8.8 ) • Tablets: Administer whole, broken in half along the score, or crush and mix in applesauce • Tablets: Can be taken with or without food

2.1Dosing Information A

daily dose of clobazam greater than 5 mg should be administered in divided doses twice daily; a 5 mg daily dose can be administered as a single dose. Dose patients according to body weight. Individualize dosing within each body weight group, based on clinical efficacy and tolerability.

Each dose in Table 1 (e.g., 5 to 20 mg in ≤30 kg weight group) has been shown to be effective, although effectiveness increases with increasing dose . Do not proceed with dose escalation more rapidly than weekly, because serum concentrations of clobazam and its active metabolite require 5 and 9 days, respectively, to reach steady-state. Table 1. Recommended Total Daily Dosing by Weight Group ≤30 kg Body Weight >30 kg Body Weight Starting Dose 5 mg 10 mg Starting Day 7 10 mg 20 mg Starting Day 14 20 mg 40 mg

2.2Discontinuation or Dosage Reduction of Clobazam Tablet

To reduce the risk of withdrawal reactions, increased seizure frequency, and status epilepticus, use a gradual taper to discontinue clobazam tablets or reduce the dosage. Taper by decreasing the total daily dose by 5 to 10 mg/day on a weekly basis until discontinued. If a patient develops withdrawal reactions, consider pausing the taper or increasing the dosage to the previous tapered dosage level.

Subsequently decrease the dosage more slowly .

2.3Important Administration Instructions Clobazam Tablet

Oral Administration Clobazam tablets can be taken with or without food. Clobazam tablets can be administered whole, broken in half along the score, or crushed and mixed in applesauce.

2.4Dosage Adjustments in Geriatric Patients Plasma

concentrations at any given dose are generally higher in the elderly: proceed slowly with dose escalation. The starting dose should be 5 mg/day for all elderly patients. Then titrate elderly patients according to weight, but to half the dose presented in Table 1, as tolerated. If necessary and based upon clinical response, an additional titration to the maximum dose (20 mg/day or 40 mg/day, depending on weight) may be started on day 21 .

2.5Dosage Adjustments in CYP2C19 Poor Metabolizers

In CYP2C19 poor metabolizers, levels of N-desmethylclobazam, clobazam’s active metabolite, will be increased. Therefore, in patients known to be CYP2C19 poor metabolizers, the starting dose should be 5 mg/day and dose titration should proceed slowly according to weight, but to half the dose presented in Table 1, as tolerated. If necessary and based upon clinical response, an additional titration to the maximum dose (20 mg/day or 40 mg/day, depending on the weight group) may be started on day 21 .

2.6Patients with Renal Impairment No

dose adjustment is required for patients with mild and moderate renal impairment. There is no experience with clobazam in patients with severe renal impairment or end stage renal disease (ESRD). It is not known if clobazam or its active metabolite, N-desmethylclobazam, is dialyzable .

2.7Dosage Adjustments in Patients with Hepatic Impairment

Clobazam is hepatically metabolized; however, there are limited data to characterize the effect of hepatic impairment on the pharmacokinetics of clobazam. For this reason, proceed slowly with dosing escalations. For patients with mild to moderate hepatic impairment (Child-Pugh score 5 to 9), the starting dose should be 5 mg/day in both weight groups.

Then titrate patients according to weight, but to half the dose presented in Table 1, as tolerated. If necessary and based upon clinical response, start an additional titration on day 21 to the maximum dose (20 mg/day or 40 mg/day, depending on the weight group). There is inadequate information about metabolism of clobazam in patients with severe hepatic impairment.

Therefore no dosing recommendation in those patients can be given .

Somnolence or Sedation: Monitor for central nervous system (CNS) depression. Risk may be increased with concomitant use of other CNS depressants ( 5.4 , 5.5 ) Serious Dermatological Reactions (including Stevens-Johnson syndrome and toxic epidermal necrolysis): Discontinue clobazam tablet at first sign of rash unless the rash is clearly not drug-related Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS)/Multiorgan Hypersensitivity: Discontinue if no alternative etiology Suicidal Behavior and Ideation: Monitor for suicidal thoughts or behaviors Neonatal Sedation and Withdrawal Syndrome: Clobazam tablet use during pregnancy can result in neonatal sedation and/or neonatal withdrawal ( 5.9 , 8.1 )

5.1Risks from Concomitant Use with Opioids Concomitant

use of benzodiazepines, including clobazam, and opioids may result in profound sedation, respiratory depression, coma, and death. Because of these risks, reserve concomitant prescribing of benzodiazepines and opioids for patients for whom alternative treatment options are inadequate. Observational studies have demonstrated that concomitant use of opioid analgesics and benzodiazepines increases the risk of drug-related mortality compared to use of opioids alone.

If a decision is made to prescribe clobazam concomitantly with opioids, prescribe the lowest effective dosages and minimum durations of concomitant use, and follow patients closely for signs and symptoms of respiratory depression and sedation. Advise both patients and caregivers about the risks of respiratory depression and sedation when clobazam is used with opioids .

5.2Abuse, Misuse, and Addiction The

use of benzodiazepines, including clobazam, exposes users to the risks of abuse, misuse, and addiction, which can lead to overdose or death. Abuse and misuse of benzodiazepines often (but not always) involve the use of doses greater than the maximum recommended dosage and commonly involve concomitant use of other medications, alcohol, and/or illicit substances, which is associated with an increased frequency of serious adverse outcomes, including respiratory depression, overdose, or death . Before prescribing clobazam and throughout treatment, assess each patient’s risk for abuse, misuse, and addiction (e.g., using a standardized screening tool). Use of clobazam, particularly in patients at elevated risk, necessitates counseling about the risks and proper use of clobazam along with monitoring for signs and symptoms of abuse, misuse, and addiction.

Prescribe the lowest effective dosage; avoid or minimize concomitant use of CNS depressants and other substances associated with abuse, misuse, and addiction (e.g., opioid analgesics, stimulants); and advise patients on the proper disposal of unused drug. If a substance use disorder is suspected, evaluate the patient and institute (or refer them for) early treatment, as appropriate.

5.3Dependence and Withdrawal Reactions To

reduce the risk of withdrawal reactions, use a gradual taper to discontinue clobazam or reduce the dosage . Patients at an increased risk of withdrawal adverse reactions after benzodiazepine discontinuation or rapid dosage reduction include those who take higher dosages, and those who have had longer durations of use. Acute Withdrawal Reactions The continued use of benzodiazepines, including clobazam, may lead to clinically significant physical dependence. Abrupt discontinuation or rapid dosage reduction of clobazam after continued use, or administration of flumazenil (a benzodiazepine antagonist) may precipitate acute withdrawal reactions, which can be life-threatening (e.g., seizures ) . Protracted Withdrawal Syndrome In some cases, benzodiazepine users have developed a protracted withdrawal syndrome with withdrawal symptoms lasting weeks to more than 12 months .

5.4Potentiation of Sedation from Concomitant Use with Central

Nervous System Depressants Since clobazam has a central nervous system (CNS) depressant effect, patients or their caregivers should be cautioned against simultaneous use with other CNS depressant drugs or alcohol, and cautioned that the effects of other CNS depressant drugs or alcohol may be potentiated .

5.5Somnolence or Sedation Clobazam

causes somnolence and sedation. In clinical trials, somnolence or sedation was reported at all effective doses and was dose-related. In general, somnolence and sedation begin within the first month of treatment and may diminish with continued treatment. Prescribers should monitor patients for somnolence and sedation, particularly with concomitant use of other central nervous system depressants.

Prescribers should caution patients against engaging in hazardous activities requiring mental alertness, such as operating dangerous machinery or motor vehicles, until the effect of clobazam is known.

5.6Serious Dermatological Reactions Serious

skin reactions, including Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), have been reported with clobazam in both children and adults during the postmarketing period. Patients should be closely monitored for signs or symptoms of SJS/TEN, especially during the first 8 weeks of treatment initiation or when re-introducing therapy. Clobazam should be discontinued at the first sign of rash, unless the rash is clearly not drug-related.

If signs or symptoms suggest SJS/TEN, use of this drug should not be resumed and alternative therapy should be considered .

5.7Drug Reaction with Eosinophilia and Systemic Symptoms

(DRESS)/Multiorgan Hypersensitivity Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS), also known as multiorgan hypersensitivity, has been reported in patients taking antiepileptic drugs, including clobazam. These events can be fatal or life-threatening, particularly if diagnosis and treatment do not occur as early as possible. DRESS typically, although not exclusively, presents with fever, rash, lymphadenopathy, and/or facial swelling, in association with other organ system involvement, such as hepatitis, nephritis, hematological abnormalities, myocarditis, or myositis, sometimes resembling an acute viral infection.

Eosinophilia is often present. Because this disorder is variable in its expression, other organ systems not noted here may be involved. It is important to note that early manifestations of hypersensitivity, such as fever or lymphadenopathy, may be present even though rash is not evident.

If such signs or symptoms are present, the patient should be evaluated immediately. Clobazam should be discontinued if an alternative etiology for the signs or symptoms cannot be established .

5.8Suicidal Behavior and Ideation Antiepileptic

drugs (AEDs), including clobazam, increase the risk of suicidal thoughts or behavior in patients taking these drugs for any indication. Patients treated with any AED for any indication should be monitored for the emergence or worsening of depression, suicidal thoughts or behavior, and/or any unusual changes in mood or behavior. Pooled analyses of 199 placebo-controlled clinical trials (mono- and adjunctive therapy) of 11 different AEDs showed that patients randomized to one of the AEDs had approximately twice the risk (adjusted relative risk 1.8, 95% confidence interval [CI]: 1.2, 2.7) of suicidal thinking or behavior compared to patients randomized to placebo.

In these trials, which had a median treatment duration of 12 weeks, the estimated incidence rate of suicidal behavior or ideation among 27,863 AED-treated patients was 0.43%, compared to 0.24% among 16,029 placebo-treated patients, representing an increase of approximately one case of suicidal thinking or behavior for every 530 patients treated. There were four suicides in drug-treated patients in the trials and none in placebo-treated patients, but the number is too small to allow any conclusion about drug effect on suicide. The increased risk of suicidal thoughts or behavior with AEDs was observed as early as one week after starting drug treatment with AEDs and persisted for the duration of treatment assessed.

Because most trials included in the analysis did not extend beyond 24 weeks, the risk of suicidal thoughts or behavior beyond 24 weeks could not be assessed. The risk of suicidal thoughts or behavior was generally consistent among drugs in the data analyzed. The finding of increased risk with AEDs of varying mechanisms of action and across a range of indications suggests that the risk applies to all AEDs used for any indication.

The risk did not vary substantially by age (5 to 100 years) in the clinical trials analyzed. Table 2 shows absolute and relative risk by indication for all evaluated AEDs. Table 2. Risk by Indication for Antiepileptic Drugs in the Pooled Analysis Indication Placebo Patients with Events per 1000 Patients Drug Patients with Events per 1000 Patients Relative Risk: Incidence of Drug Events in Drug Patients/Incidence in Placebo Patients Risk Difference: Additional Drug Patients with Events per 1000 Patients Epilepsy 1 3.4 3.5

2.4Psychiatric

5.7 8.5 1.5

2.9Other

1 1.8 1.9

0.9Total

2.4 4.3 1.8

1.9The

relative risk for suicidal thoughts or behavior was higher in clinical trials for epilepsy than in clinical trials for psychiatric or other conditions, but the absolute risk differences were similar for the epilepsy and psychiatric indications. Anyone considering prescribing clobazam or any other AED must balance the risk of suicidal thoughts or behavior with the risk of untreated illness. Epilepsy and many other illnesses for which AEDs are prescribed are themselves associated with morbidity and mortality and an increased risk of suicidal thoughts and behavior.

Should suicidal thoughts and behavior emerge during treatment, the prescriber needs to consider whether the emergence of these symptoms in any given patient may be related to the illness being treated. Patients, their caregivers, and families should be informed that AEDs increase the risk of suicidal thoughts and behavior and should be advised of the need to be alert for the emergence or worsening of the signs and symptoms of depression, any unusual changes in mood or behavior, or the emergence of suicidal thoughts, behavior, or thoughts about self-harm. Behaviors of concern should be reported immediately to healthcare providers.

5.9Neonatal Sedation and Withdrawal Syndrome Use

of clobazam late in pregnancy can result in sedation (respiratory depression, lethargy, hypotonia) and/or withdrawal symptoms (hyperreflexia, irritability, restlessness, tremors, inconsolable crying, and feeding difficulties) in the neonate . Monitor neonates exposed to clobazam during pregnancy or labor for signs of sedation and monitor neonates exposed to clobazam during pregnancy for signs of withdrawal; manage these neonates accordingly.

Clobazam tablets are contraindicated in patients with a history of hypersensitivity to the drug or its ingredients. Hypersensitivity reactions have included serious dermatological reactions . History of hypersensitivity to the drug or its ingredients

8.1Pregnancy Pregnancy Registry There

is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to AEDs, such as clobazam, during pregnancy. Healthcare providers are encouraged to recommend that pregnant women taking clobazam enroll in the North American Antiepileptic Drug (NAAED) Pregnancy Registry by calling 1-888-233-2334 or online at http://www.aedpregnancyregistry.org/. Risk Summary Neonates born to mothers using benzodiazepines late in pregnancy have been reported to experience symptoms of sedation and/or neonatal withdrawal . Available data from published observational studies of pregnant women exposed to benzodiazepines do not report a clear association with benzodiazepines and major birth defects . Administration of clobazam to pregnant rats and rabbits during the period of organogenesis or to rats throughout pregnancy and lactation resulted in developmental toxicity, including increased incidences of fetal malformations and mortality, at plasma exposures for clobazam and its major active metabolite, N-desmethylclobazam, below those expected at therapeutic doses in patients . Data for other benzodiazepines suggest the possibility of long-term effects on neurobehavioral and immunological function in animals following prenatal exposure to benzodiazepines at clinically relevant doses. Clobazam should be used during pregnancy only if the potential benefit to the mother justifies the potential risk to the fetus.

Advise a pregnant woman and women of childbearing age of the potential risk to a fetus. The background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and of miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively.

Clinical Considerations Fetal/Neonatal Adverse Reactions Benzodiazepines cross the placenta and may produce respiratory depression, hypotonia, and sedation in neonates. Monitor neonates exposed to clobazam during pregnancy or labor for signs of sedation, respiratory depression, hypotonia, and feeding problems. Monitor neonates exposed to clobazam during pregnancy for signs of withdrawal.

Manage these neonates accordingly . Data Human Data Published data from observational studies on the use of benzodiazepines during pregnancy do not report a clear association with benzodiazepines and major birth defects. Although early studies reported an increased risk of congenital malformations with diazepam and chlordiazepoxide, there was no consistent pattern noted. In addition, the majority of more recent case-control and cohort studies of benzodiazepine use during pregnancy, which were adjusted for confounding exposures to alcohol, tobacco and other medications, have not confirmed these findings.

Animal Data In a study in which clobazam (0, 150, 450, or 750 mg/kg/day) was orally administered to pregnant rats throughout the period of organogenesis, embryofetal mortality and incidences of fetal skeletal variations were increased at all doses. The low-effect dose for embryofetal developmental toxicity in rats (150 mg/kg/day) was associated with plasma exposures (AUC) for clobazam and its major active metabolite, N-desmethylclobazam, lower than those in humans at the maximum recommended human dose (MRHD) of 40 mg/day. Oral administration of clobazam (0, 10, 30, or 75 mg/kg/day) to pregnant rabbits throughout the period of organogenesis resulted in decreased fetal body weights, and increased incidences of fetal malformations (visceral and skeletal) at the mid and high doses, and an increase in embryofetal mortality at the high dose.

Incidences of fetal variations were increased at all doses. The highest dose tested was associated with maternal toxicity (ataxia and decreased activity). The low-effect dose for embryofetal developmental toxicity in rabbits (10 mg/kg/day) was associated with plasma exposures for clobazam and N-desmethylclobazam lower than those in humans at the MRHD. Oral administration of clobazam (0, 50, 350, or 750 mg/kg/day) to rats throughout pregnancy and lactation resulted in increased embryofetal mortality at the high dose, decreased pup survival at the mid and high doses and alterations in offspring behavior (locomotor activity) at all doses.

The low-effect dose for adverse effects on pre- and postnatal development in rats (50 mg/kg/day) was associated with plasma exposures for clobazam and N-desmethylclobazam lower than those in humans at the MRHD.

8.3Females and Males of Reproductive Potential Administration

of clobazam to rats prior to and during mating and early gestation resulted in adverse effects on fertility and early embryonic development at plasma exposures for clobazam and its major active metabolite, N-desmethylclobazam, below those in humans at the MRHD .

Clinically significant adverse reactions that appear in other sections of the labeling include the following: • Risks from Concomitant Use with Opioids • Abuse, Misuse, and Addiction • Dependence and Withdrawal Reactions • Potentiation of Sedation from Concomitant Use with Central Nervous System Depressants • Somnolence or Sedation • Serious Dermatological Reactions • Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS)/Multiorgan Hypersensitivity • Suicidal Behavior and Ideation • Neonatal Sedation and Withdrawal Syndrome Adverse reactions that occurred at least 10% more frequently than placebo in any clobazam tablet dose included constipation, somnolence or sedation, pyrexia, lethargy, and drooling To report SUSPECTED ADVERSE REACTIONS, contact Micro Labs USA, Inc. at 1-855-839-8195 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6.1Clinical 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. During its development for the adjunctive treatment of seizures associated with LGS, clobazam was administered to 333 healthy volunteers and 300 patients with a current or prior diagnosis of LGS, including 197 patients treated for 12 months or more. The conditions and duration of exposure varied greatly and included single- and multiple- dose clinical pharmacology studies in healthy volunteers and two double-blind studies in patients with LGS (Study 1 and 2) . Only Study 1 included a placebo group, allowing comparison of adverse reaction rates on clobazam at several doses to placebo.

Adverse Reactions Leading to Discontinuation in an LGS Placebo Controlled Clinical Trial (Study 1) The adverse reactions associated with clobazam treatment discontinuation in ≥1% of patients in decreasing order of frequency included lethargy, somnolence, ataxia, aggression, fatigue, and insomnia. Most Common Adverse Reactions in an LGS Placebo Controlled Clinical Trial (Study 1) Table 3 lists the adverse reactions that occurred in ≥5% of clobazam-treated patients (at any dose), and at a rate greater than placebo-treated patients, in the randomized, double-blind, placebo-controlled, parallel group clinical study of adjunctive AED therapy for 15 weeks (Study 1). Table 3.

Adverse Reactions Reported for ≥5% of Patients and More Frequently than Placebo in Any Treatment Group Placebo N=59% Clobazam Dose Level All Clobazam N=179% Low a N=58% Medium b N=62% High c N=59% Gastrointestinal Disorders Vomiting 5 9 5 7 7 Constipation 0 2 2 10 5 Dysphagia 0 0 0 5 2 General Disorders and Administration Site Conditions Pyrexia 3 17 10 12 13 Irritability 5 3 11 5 7 Fatigue 2 5 5 3 5 Infections and Infestations Upper respiratory tract infection 10 10 13 14 12 Pneumonia 2 3 3 7 4 Urinary tract infection 0 2 5 5 4 Bronchitis 0 2 0 5 2 Metabolism and Nutrition Disorders Decreased appetite 3 3 0 7 3 Increased appetite 0 2 3 5 3 Nervous System Disorders Somnolence or Sedation 15 17 27 32 26 Somnolence 12 16 24 25 22 Sedation 3 2 3 9 5 Lethargy 5 10 5 15 10 Drooling 3 0 13 14 9 Ataxia 3 3 2 10 5 Psychomotor hyperactivity 3 3 3 5 4 Dysarthria 0 2 2 5 3 Psychiatric Disorders Aggression 5 3 8 14 8 Insomnia 2 2 5 7 5 Respiratory Disorders Cough 0 3 5 7 5 a Maximum daily dose of 5 mg for ≤30 kg body weight; 10 mg for >30 kg body weight b Maximum daily dose of 10 mg for ≤30 kg body weight; 20 mg for >30 kg body weight c Maximum daily dose of 20 mg for ≤30 kg body weight; 40 mg for >30 kg body weight

6.2Postmarketing Experience These

reactions are reported voluntarily from a population of uncertain size; therefore, it is not possible to estimate their frequency or establish a causal relationship to drug exposure. Adverse reactions are categorized by system organ class. Blood Disorders: Anemia, eosinophilia, leukopenia, thrombocytopenia Eye Disorders: Diplopia, vision blurred Gastrointestinal Disorders: Abdominal distention General Disorders and Administration Site Conditions: Hypothermia Investigations: Hepatic enzyme increased Musculoskeletal: Muscle spasms Psychiatric Disorders: Agitation, anxiety, apathy, confusional state, depression, delirium, delusion, hallucination Renal and Urinary Disorders: Urinary retention Respiratory Disorders: Aspiration, respiratory depression Skin and Subcutaneous Tissue Disorders: Rash, urticaria, angioedema, and facial and lip edema