Clozapine

FDA Drug Information • Also known as: Clozapine, Clozaril, Versacloz

Brand Names: Clozapine, Clozaril, Versacloz
Drug Class: Atypical Antipsychotic [EPC]
Route: ORAL
Dosage Form: TABLET, ORALLY DISINTEGRATING
Product Type: HUMAN PRESCRIPTION DRUG

⚠ Boxed Warning (Black Box)

WARNING: SEVERE NEUTROPENIA; ORTHOSTATIC HYPOTENSION, BRADYCARDIA, AND SYNCOPE; SEIZURE; MYOCARDITIS, PERICARDITIS, AND CARDIOMYOPATHY; INCREASED MORTALITY IN ELDERLY PATIENTS WITH DEMENTIA-RELATED PSYCHOSIS Severe Neutropenia Clozapine has caused severe neutropenia which is associated with an increased risk of serious and potentially fatal infections. Prior to initiating clozapine treatment, obtain baseline ANC(s). Clozapine initiation is not recommended in patients with a baseline ANC less than 1500/μL (less than 1000/μL for those with Benign Ethnic Neutropenia (also known as Duffy-null associated neutrophil count)). See recommendations for dosage modifications based on ANC levels during clozapine treatment [see Dosage and Administration (2.3 , 2.4) ]. Consider a hematology consultation before initiating clozapine or during clozapine treatment [see Warnings and Precautions (5.1) ]. Orthostatic Hypotension, Bradycardia, Syncope Orthostatic hypotension, bradycardia, syncope, and cardiac arrest have occurred with clozapine treatment. The risk is highest during the initial titration period, particularly with rapid dose escalation. These reactions can occur with the first dose, with doses as low as 12.5 mg per day , or when restarting patients who have had even a brief interruption in treatment with clozapine. Initiate treatment at 12.5 mg once or twice daily; titrate slowly; and use divided dosages to minimize risk . Use clozapine cautiously in patients with cardiovascular or cerebrovascular disease or conditions predisposing to hypotension (e.g., dehydration, use of antihypertensive medications) [see Dosage and Administration (2.2 , 2.6) , Warnings and Precautions (5.2) ]. Seizures Seizures have occurred with clozapine treatment. The risk is dose-related. Initiate treatment at 12.5 mg, titrate gradually, and use divided dosing. Use caution when administering clozapine to patients with a history of seizures or other predisposing risk factors for seizure (CNS pathology, medications that lower the seizure threshold, alcohol abuse). Caution patients about engaging in any activity where sudden loss of consciousness could cause serious risk to themselves or others [see Dosage and Administration (2.2) , Warnings and Precautions (5.4) ]. Myocarditis, Pericarditis, Cardiomyopathy and Mitral Valve Incompetence Fatal myocarditis and cardiomyopathy have occurred with clozapine treatment. Discontinue clozapine and obtain a cardiac evaluation upon suspicion of these reactions. Generally, patients with clozapine-related myocarditis or cardiomyopathy should not be rechallenged with clozapine . Consider the possibility of myocarditis, pericarditis, or cardiomyopathy if chest pain, tachycardia, palpitations, dyspnea, fever, flu-like symptoms, hypotension, or ECG changes occur [see Warnings and Precautions (5.5) ] . Increased Mortality in Elderly Patients with Dementia-Related Psychosis Elderly patients with dementia-related psychosis treated with antipsychotic drugs are at an increased risk of death. C lozapine is not approved for use in patients with dementia-related psychosis [see Warnings and Precautions (5.6) ]. WARNING: SEVERE NEUTROPENIA; ORTHOSTATIC HYPOTENSION, BRADYCARDIA, AND SYNCOPE; SEIZURE; MYOCARDITIS, PERICARDITIS, AND CARDIOMYOPATHY; INCREASED MORTALITY IN ELDERLY PATIENTS WITH DEMENTIA-RELATED PSYCHOSIS See full prescribing information for complete boxed warning . Severe Neutropenia: Clozapine has caused severe neutropenia, which is associated with an increased risk of serious and fatal infections. Prior to initiating clozapine treatment, obtain baseline ANC(s). Clozapine initiation is not recommended in patients with a baseline ANC less than 1500/μL (less than 1000/μL for those with Benign Ethnic Neutropenia (also known as Duffy-null associated neutrophil count)). See recommendations for dosage modifications based on ANC levels during clozapine treatment ( 2.3 , 2.4 , 5.1 ). Orthostatic Hypotension, Bradycardia, and Syncope: Risk is dose-related. Starting dose is 12.5 mg. Titrate gradually and use divided dosages. ( 2.2 , 2.6 , 5.2 ) Seizure: Risk is dose-related. Titrate gradually and use divided doses. Use with caution in patients with history of seizure or risk factors for seizure. ( 2.2 , 5.4 ) Myocarditis, Pericarditis, Cardiomyopathy and Mitral Valve Incompetence: Can be fatal. Discontinue and obtain cardiac evaluation if findings suggest these cardiac reactions. ( 5.5 ) Increased Mortality in Elderly Patients with Dementia-Related Psychosis: Clozapine is not approved for this condition. ( 5.6 )

Description

11 DESCRIPTION Clozapine, an atypical antipsychotic drug, is a tricyclic dibenzodiazepine derivative, 8-chloro-11-(4-methyl-1-piperazinyl)-5 H -dibenzo [ b,e ] [1,4] diazepine. The structural formula is: Clozapine USP is available in pale yellow colored tablets of 25 mg, 50 mg, 100 mg, and 200 mg for oral administration. Active Ingredient: clozapine Inactive Ingredients are colloidal silicon dioxide, corn starch, lactose monohydrate, magnesium stearate, povidone, and talc. Chemical Structure

What Is Clozapine Used For?

1 INDICATIONS AND USAGE Clozapine tablets are an atypical antipsychotic indicated for: Treatment of severely ill patients with schizophrenia who fail to respond adequately to standard antipsychotic treatment. Because of the risks of severe neutropenia and of seizure associated with its use, clozapine tablets should be used only in patients who have failed to respond adequately to standard antipsychotic treatment. ( 1.1 ) Reducing the risk of recurrent suicidal behavior in patients with schizophrenia or schizoaffective disorder who are judged to be at chronic risk for re-experiencing suicidal behavior. ( 1.2 ) 1.1 Treatment-Resistant Schizophrenia Clozapine tablets are indicated for the treatment of severely ill patients with schizophrenia who fail to respond adequately to standard antipsychotic treatment. Because of the risks of severe neutropenia and of seizure associated with its use, clozapine tablets should be used only in patients who have failed to respond adequately to standard antipsychotic treatment [see Warnings and Precautions (5.1 , 5.4) ]. The effectiveness of clozapine tablets in treatment-resistant schizophrenia was demonstrated in a 6-week, randomized, double-blind, active-controlled study comparing clozapine tablets and chlorpromazine in patients who had failed other antipsychotics [see Clinical Studies (14.1) ]. 1.2 Reduction in the Risk of Recurrent Suicidal Behavior in Schizophrenia or Schizoaffective Disorder Clozapine tablets are indicated for reducing the risk of recurrent suicidal behavior in patients with schizophrenia or schizoaffective disorder who are judged to be at chronic risk for re-experiencing suicidal behavior, based on history and recent clinical state. Suicidal behavior refers to actions by a patient that put him/herself at risk for death. The effectiveness of clozapine tablets in reducing the risk of recurrent suicidal behavior was demonstrated over a two-year treatment period in the InterSePT™ trial [see Clinical Studies (14.2) ] .

Dosage and Administration

2 DOSAGE AND ADMINISTRATION Recommended starting oral dosage is 12.5 mg once daily or twice daily. ( 2.2 ) If well-tolerated, increase the total daily dosage in increments of 25 mg to 50 mg per day to achieve a target dosage of 150 mg to 225 mg twice per day by the end of two weeks ( 2.2 ). Subsequently may increase the dosage in increments up to 100 mg once or twice weekly ( 2.2 ). Maximum daily dosage is 450 mg twice daily ( 2.2 ). Administer with or without food ( 2.2 ). See the dosage modifications based on ANC results and recommended frequency of ANC testing in the full prescribing information ( 2.3 , 2.4 ). See recommendations for discontinuing clozapine tablets treatment (2.5), restarting clozapine tablets after interrupting dosing ( 2.6 ), dosage modifications for drug interactions (2.7), dosage recommendations in patients with renal or hepatic impairment and CYP2D6 poor metabolizers ( 2.8 ) in the full prescribing information. 2.1 Absolute Neutrophil Count Testing Prior to Clozapine Tablets Initiation Prior to initiating clozapine tablets treatment, obtain a baseline absolute neutrophil count (ANC). Clozapine tablets initiation is not recommended in patients with an ANC less than 1500/μL [see Warnings and Precautions (5.1) ] . For patients with documented Benign Ethnic Neutropenia (BEN) (also known as Duffy-null associated neutrophil count), obtain at least two baseline ANC levels. Clozapine tablets initiation is not recommended in patients with BEN with an ANC less than 1000/μL [see Warnings and Precautions (5.1) ] . For dosage modifications based on ANC results, see Dosage and Administration (2.3 , 2.4) . 2.2 Recommended Dosage and Administration To reduce the risk of orthostatic hypotension, bradycardia, and syncope, the recommended starting dosage is much lower than the target dosage [see Warnings and Precautions (5.2) ] . Clozapine tablets can be taken with or without food [see Clinical Pharmacology (12.3) ] . The recommended starting oral dosage of clozapine tablets is 12.5 mg once or twice daily. If well-tolerated, increase the total daily dose in increments of 25 mg to 50 mg per day to achieve a target dosage of 150 mg to 225 mg twice per day by the end of two weeks. Subsequently, may increase the dosage in increments of up to 100 mg once weekly or twice weekly. The maximum recommended clozapine tablets oral dosage is 450 mg twice daily. 2.3 Dosage Modifications Based on ANC Results Table 1 provides recommended clozapine tablets dosage modifications based on ANC results [see Warnings and Precautions (5.1) ]. For dosage modifications based on ANC results for patients with Benign Ethnic Neutropenia (BEN) (also known as Duffy-null associated neutrophil count), see Table 2 [see Dosage and Administration (2.4) ]. Table 1. Clozapine Tablets Dosage Modifications Based on ANC Results and Frequency of ANC Testing 1 Confirm all initial reports of ANC less than 1500/μL with a repeat ANC measurement within 24 hours Recommended Dosage...

Side Effects (Adverse Reactions)

6 ADVERSE REACTIONS The following adverse reactions are discussed in more detail in other sections of the labeling: Severe Neutropenia [see Warnings and Precautions (5.1) ] Orthostatic Hypotension, Bradycardia, and Syncope [see Warnings and Precautions (5.2) ] Falls [see Warnings and Precautions (5.3) ] Seizures [see Warnings and Precautions (5.4) ] Myocarditis, Pericarditis, Cardiomyopathy, and Mitral Valve Incompetence [see Warnings and Precautions (5.5) ] Increased Mortality in Elderly Patients with Dementia-Related Psychosis [see Warnings and Precautions (5.6) ] Gastrointestinal Hypomotility with Severe Complications [See Warnings and Precautions (5.7) ] Eosinophilia [see Warnings and Precautions (5.8) ] QT Interval Prolongation [see Warnings and Precautions (5.9) ] Metabolic Changes (Hyperglycemia and Diabetes Mellitus, Dyslipidemia, and Weight Gain) [see Warnings and Precautions (5.10) ] Neuroleptic Malignant Syndrome [see Warnings and Precautions (5.11) ] Hepatotoxicity [see Warnings and Precautions (5.12) ] Fever [see Warnings and Precautions (5.13) ] Pulmonary Embolism [see Warnings and Precautions (5.14) ] Anticholinergic Toxicity [see Warnings and Precautions (5.15) ] Interference with Cognitive and Motor Performance [see Warnings and Precautions (5.16) ] Tardive Dyskinesia [see Warnings and Precautions (5.17) ] Cerebrovascular Adverse Reactions [see Warnings and Precautions (5.18) ] Recurrence of Psychosis and Cholinergic Rebound after Abrupt Discontinuation [see Warnings and Precautions (5.19) ] Most common adverse reactions (≥5%) were: CNS reactions (sedation, dizziness/vertigo, headache, and tremor); cardiovascular reactions (tachycardia, hypotension, and syncope); autonomic nervous system reactions (hypersalivation, sweating, dry mouth, and visual disturbances); gastrointestinal reactions (constipation and nausea); and fever. (6.1) To report SUSPECTED ADVERSE REACTIONS, contact Aurobindo Pharma USA, Inc. at 1-866-850-2876 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 clinical practice. The most commonly reported adverse reactions (≥5%) across clozapine clinical trials were: CNS reactions, including sedation, dizziness/vertigo, headache, and tremor; cardiovascular reactions, including tachycardia, hypotension, and syncope; autonomic nervous system reactions, including hypersalivation, sweating, dry mouth, and visual disturbances; gastrointestinal reactions, including constipation and nausea; and fever. Table 9 summarizes the most commonly reported adverse reactions (≥5%) in clozapine-treated patients (compared to chlorpromazine-treated patients) in the pivotal, 6-week, controlled trial in treatment-resistant schizophrenia. Table 9. Common Adverse Reactions (≥5%) in the 6-Week, Randomized, Chlorpromazine-controlled Trial in Treatment-Resistant Schizophrenia Adverse Reaction Clozapine (N=126) (%) Chlorpromazine (N=142) (%) Sedation 21 13 Tachycardia 17 11 Constipation 16 12 Dizziness 14 16 Hypotension 13 38 Fever (hyperthermia) 13 4 Hypersalivation 13 1 Hypertension 12 5 Headache 10 10 Nausea/vomiting 10 12 Dry mouth 5 20 Table 10 summarizes the adverse reactions reported in clozapine-treated patients at a frequency of 2% or greater across all clozapine studies (excluding the 2-year InterSePT™ Study). These rates are not adjusted for duration of exposure. Table 10. Adverse Reactions (≥2%) Reported in Clozapine-treated Patients (N=842) Across all Clozapine Studies (excluding the 2-year InterSePT TM Study) Body System Adverse Reaction* Clozapine N=842 Percentage of Patients Central Nervous System Drowsiness/Sedation 39 Dizziness/Vertigo 19 Headache 7 Tremor 6 Syncope 6 Disturbed Sleep/Nightmares 4 Restlessness 4...

Drug Interactions

7 DRUG INTERACTIONS Concomitant use of Strong CYP1A2 Inhibitors : Reduce clozapine dose to one-third when coadministered with strong CYP1A2 inhibitors (e.g., fluvoxamine, ciprofloxacin, enoxacin). ( 2.7 , 7.1 ) Concomitant use of Strong CYP3A4 Inducers is not recommended. ( 2.7 , 7.1 ) Discontinuation of CYP1A2 or CYP3A4 Inducers : Consider reducing clozapine dose when CYP1A2 inducers (e.g., tobacco smoke) or CYP3A4 inducers (e.g., carbamazepine) are discontinued. ( 2.7 , 7.1 ) Anticholinergic drugs: Concomitant use may increase the risk for anticholinergic toxicity. ( 5.7 , 5.15 , 7.1 ) 7.1 Potential for Other Drugs to Affect Clozapine Clozapine is a substrate for many cytochrome P450 isozymes, in particular CYP1A2, CYP3A4, and CYP2D6. Use caution when administering clozapine concomitantly with drugs that are inducers or inhibitors of these enzymes. CYP1A2 Inhibitors Concomitant use of clozapine and CYP1A2 inhibitors can increase plasma levels of clozapine, potentially resulting in adverse reactions. Reduce the clozapine dose to one-third of the original dose when clozapine is coadministered with strong CYP1A2 inhibitors (e.g., fluvoxamine, ciprofloxacin, or enoxacin). The clozapine dose should be increased to the original dose when coadministration of strong CYP1A2 inhibitors is discontinued [see Dosage and Administration (2.7) , Clinical Pharmacology (12.3) ]. Moderate or weak CYP1A2 inhibitors include oral contraceptives and caffeine. Monitor patients closely when clozapine is coadministered with these inhibitors. Consider reducing the clozapine dosage if necessary [see Dosage and Administration (2.7) ]. CYP2D6 and CYP3A4 Inhibitors Concomitant treatment with clozapine and CYP2D6 or CYP3A4 inhibitors (e.g., cimetidine, escitalopram, erythromycin, paroxetine, bupropion, fluoxetine, quinidine, duloxetine, terbinafine, or sertraline) can increase clozapine levels and lead to adverse reactions [see Clinical Pharmacology (12.3) ] . Use caution and monitor patients closely when using such inhibitors. Consider reducing the clozapine dose [see Dosage and Administration (2.7) ]. CYP1A2 and CYP3A4 Inducers Concomitant treatment with drugs that induce CYP1A2 or CYP3A4 can decrease the plasma concentration of clozapine, resulting in decreased effectiveness of clozapine. Tobacco smoke is a moderate inducer of CYP1A2. Strong CYP3A4 inducers include carbamazepine, phenytoin, St. John’s wort, and rifampin. It may be necessary to increase the clozapine dose if used concomitantly with inducers of these enzymes. However, concomitant use of clozapine and strong CYP3A4 inducers is not recommended [see Dosage and Administration (2.7) ] . Consider reducing the clozapine dosage when discontinuing coadministered enzyme inducers; because discontinuation of inducers can result in increased clozapine plasma levels and an increased risk of adverse reactions [see Dosage and Administration (2.7) ] . Anticholinergic Drugs Concomitant treatment with clozapine and other...

Contraindications

4 CONTRAINDICATIONS Clozapine tablets are contraindicated in patients with a history of hypersensitivity to clozapine (e.g., photosensitivity, vasculitis, erythema multiforme, or Stevens-Johnson syndrome) or any other component of clozapine tablets [see Adverse Reactions (6.2) ] . Known hypersensitivity to clozapine or any other component of clozapine tablets. ( 4 )

Pregnancy and Breastfeeding

8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to atypical antipsychotics, including clozapine, during pregnancy. Healthcare providers are encouraged to advise patients to register by calling the National Pregnancy Registry for Atypical Antipsychotics at1-866-961-2388 or visiting http://womensmentalhealth.org/clinical-and-research-programs/pregnancyregistry/. Risk Summary Neonates exposed to antipsychotic drugs, including clozapine, during the third trimester are at risk for extrapyramidal and/or withdrawal symptoms following delivery ( see Clinical Considerations ). Available data from published epidemiologic studies over decades of use with clozapine during pregnancy have not established a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes ( see Data ). There are risks to the mother associated with untreated schizophrenia and with exposure to antipsychotics, including clozapine, during pregnancy ( see Clinical Considerations ). In animal reproduction studies, no adverse developmental effects were observed when clozapine was administered orally to pregnant rats or rabbits during the period of organogenesis, or to pregnant rats during pregnancy and lactation, at doses up to approximately 0.4 and 0.9 times the maximum recommended human dose (MRHD) of 900 mg/day, for rats and rabbits respectively, based on mg/m 2 body surface area ( see Data ). The background risk of major birth defects and miscarriage for the indicated populations is unknown. All pregnancies have a background risk of birth defects, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively. Clinical Considerations Disease-associated maternal and/or embryo/fetal risk There is a risk to the mother from untreated schizophrenia,...

Overdosage

10 OVERDOSAGE 10.1 Overdosage Experience The most commonly reported signs and symptoms associated with clozapine overdose are: sedation, delirium, coma, tachycardia, hypotension, respiratory depression or failure; and hypersalivation. There are reports of aspiration pneumonia, cardiac arrhythmias, and seizure. Fatal overdoses have been reported with clozapine, generally at doses above 2500 mg. There have also been reports of patients recovering from overdoses well in excess of 4 g. 10.2 Management of Overdosage There is no available specific antidote to an overdose of clozapine. Establish and maintain an airway; ensure adequate oxygenation and ventilation. Monitor cardiac status and vital signs. Use general symptomatic and supportive measures. Consider the possibility of multiple-drug involvement. Contact a Certified Poison Control Center for the most up to date information on the management of overdosage (1-800-222-1222).

How Supplied

16 HOW SUPPLIED/STORAGE AND HANDLING 16.1 How Supplied Clozapine Tablets USP, 25 mg are pale yellow colored, round, flat faced, bevel edged uncoated tablets debossed with ‘C facilitated scoreline (functional) C’ on one side and ‘54’ on the other side. Bottles of 100 NDC 65862-844-01 Bottles of 500 NDC 65862-844-05 10 x 10 Unit-dose Tablets NDC 65862-844-78 Clozapine Tablets USP, 50 mg are pale yellow colored, round, flat faced, bevel edged uncoated tablets debossed with ‘C facilitated scoreline (functional) C’ on one side and ‘55’ on the other side. Bottles of 100 NDC 65862-845-01 Bottles of 500 NDC 65862-845-05 10 x 10 Unit-dose Tablets NDC 65862-845-78 Clozapine Tablets USP, 100 mg are pale yellow colored, round, flat faced, bevel edged uncoated tablets debossed with ‘C facilitated scoreline (functional) C’ on one side and ‘57’ on the other side. Bottles of 100 NDC 65862-846-01 Bottles of 500 NDC 65862-846-05 10 x 10 Unit-dose Tablets NDC 65862-846-78 Clozapine Tablets USP, 200 mg are pale yellow colored, oval shaped, uncoated tablets debossed with ‘C scoreline (functional) C’ on one side and ‘71’ on the other side. Bottles of 100 NDC 65862-847-01 Bottles of 500 NDC 65862-847-05 10 x 10 Unit-dose Tablets NDC 65862-847-78 16.2 Storage and Handling Store clozapine tablets, USP at room temperature between 20° to 25°C (68° to 77°F); excursions permitted to 15° to 30°C (59° to 86°F) [See USP Controlled Room Temperature]. Keep out of reach of children.

About This Information

This drug information is sourced from FDA-approved labeling via the openFDA database. It is intended for educational and reference purposes only. This is not medical advice. Always consult your healthcare provider before making decisions about medication. Drug information may be updated by the FDA; check with your pharmacist for the most current information.

What are side effects?

Side effects are unwanted reactions that can occur when taking a medication. They range from mild (headache, nausea) to severe (allergic reactions, organ damage). Not everyone experiences side effects, and severity varies. Report any concerning side effects to your doctor.

What are drug interactions?

Drug interactions occur when a medication is affected by another drug, food, or supplement. Interactions can make medications less effective or cause dangerous side effects. Always tell your doctor about all medications and supplements you take.