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Drug Safety-related Labeling Changes (SrLC)

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CLOZARIL (NDA-019758)

(CLOZAPINE)

Safety-related Labeling Changes Approved by FDA Center for Drug Evaluation and Research (CDER)

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06/13/2025 (SUPPL-107)

Approved Drug Label (PDF)

Boxed Warning

Additions and/or revisions underlined:

Severe Neutropenia

CLOZARIL has caused severe neutropenia which is associated with an increased risk of serious and potentially fatal infections. Prior to initiating CLOZARIL treatment, obtain baseline ANC(s). CLOZARIL initiation is not recommended in patients with a baseline ANC less than 1500/mcgL (less than 1000/mcgL for those with Benign Ethnic Neutropenia (also known as Duffy-null associated neutrophil count)). See recommendations for dosage modifications based on ANC levels during CLOZARIL treatment [see Dosage and Administration (2.3, 2.4)].

Consider a hematology consultation before initiating CLOZARIL or during CLOZARIL treatment [see Warnings and Precautions (5.1)].

5 Warnings and Precautions

5.1 Severe Neutropenia

Extensive changes; please refer to label for complete information

17 PCI/PI/MG (Patient Counseling Information/Patient Information/Medication Guide)

PATIENT COUNSELING INFORMATION

Additions and/or revisions underlined:

Advise the patient to read the FDA-approved patient labeling (Medication Guide). Discuss the following issues with patients and caregivers:

. . .

    • About the importance of having frequent ANC testing.

. . .

  • Missed Doses and Re-initiating Treatment: Inform patients and caregivers that if the patient misses taking CLOZARIL for 1 day or more, they should not restart their medication at the same dosage but should contact their physician for dosing instructions [see Dosage and Administration (2.6), Warnings and Precautions (5.1, 5.2)].


MEDICATION GUIDE

Newly added section; please refer to label for complete information

01/22/2025 (SUPPL-106)

Approved Drug Label (PDF)

Boxed Warning

Additions and/or revisions underlined:

WARNING: SEVERE NEUTROPENIA; ORTHOSTATIC HYPOTENSION, BRADYCARDIA, AND SYNCOPE; SEIZURE; MYOCARDITIS, PERICARDITIS, AND CARDIOMYOPATHY; INCREASED MORTALITY IN ELDERLY PATIENTS WITH DEMENTIA-RELATED PSYCHOSIS

Myocarditis, Pericarditis, Cardiomyopathy and Mitral Valve Incompetence

Fatal myocarditis and cardiomyopathy have occurred with CLOZARIL treatment. Discontinue CLOZARIL and obtain a cardiac evaluation upon suspicion of these reactions. Generally, patients with CLOZARIL-related myocarditis or cardiomyopathy should not be rechallenged with CLOZARIL. 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 (5.6)].

5 Warnings and Precautions

5.6 Myocarditis, Pericarditis, Cardiomyopathy and Mitral Valve Incompetence

Section title revised

Additions and/or revisions underlined:

Myocarditis, pericarditis, and cardiomyopathy have occurred with the use of CLOZARIL. These reactions can be fatal. Discontinue CLOZARIL and obtain a cardiac evaluation upon suspicion of myocarditis or cardiomyopathy. Generally, patients with a history of clozapine-associated myocarditis or cardiomyopathy should not be rechallenged with CLOZARIL. However, if the benefit of CLOZARIL treatment is judged to outweigh the potential risks of recurrence, the clinician may consider rechallenge with CLOZARIL in consultation with a cardiologist.

Myocarditis and pericarditis most frequently present within the first 2 months of clozapine treatment. Symptoms of cardiomyopathy generally occur later than clozapine-associated myocarditis or pericarditis and usually after 8 weeks of treatment. However, myocarditis, pericarditis, and cardiomyopathy can occur at any period during treatment with CLOZARIL. In patients who are diagnosed with cardiomyopathy while taking CLOZARIL mitral valve incompetence has been reported.

6 Adverse Reactions

Addition of the following to the bulleted line listing:

  • Myocarditis, Pericarditis, Cardiomyopathy, and Mitral Valve Incompetence [see Warnings and Precautions (5.6)]

6.2 Postmarketing Experience

Additions and/or revisions underlined:

Cardiovascular System

Atrial or ventricular fibrillation, ventricular tachycardia, palpitations, QT interval prolongation, Torsades de Pointes, mitral valve incompetence associated with clozapine-related cardiomyopathy, myocardial infarction, cardiac arrest, myocarditis, pericarditis, and periorbital edema.

Endocrine System Pseudopheochromocytoma Gastrointestinal System

Acute pancreatitis, dysphagia, salivary gland swelling, colitis, megacolon, fecal incontinence, and intestinal ischemia, infarction, perforation, ulceration or necrosis.

09/12/2024 (SUPPL-104)

Approved Drug Label (PDF)

8 Use in Specific Populations

8.1 Pregnancy

PLLR conversion:

Pregnancy Exposure Registry

There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to atypical antipsychotics, including CLOZARIL, 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 CLOZARIL, 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 CLOZARIL, 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/m2 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, including increased risk of relapse, hospitalization, and suicide. Schizophrenia is associated with increased adverse perinatal outcomes, including preterm birth. It is not known if this is a direct result of the illness or other comorbid factors.

Fetal/Neonatal adverse reactions

Extrapyramidal and/or withdrawal symptoms, including agitation, hypertonia, hypotonia, tremor, somnolence, respiratory distress, and feeding disorder have been reported in neonates who have been exposed to antipsychotic drugs, including CLOZARIL, during the third trimester of pregnancy. These symptoms have varied in severity. Monitor neonates for extrapyramidal and/or withdrawal symptoms and manage symptoms appropriately. Some neonates recovered within hours or days without specific treatment; others required prolonged hospitalization.

Data

Animal Data

In embryofetal developmental studies, clozapine had no effects on maternal parameters, litter sizes, or fetal parameters when administered orally to pregnant rats and rabbits during the period of organogenesis at doses up to 0.4 and 0.9 times, respectively, the MRHD of 900 mg/day on a mg/m2 body surface area basis.

In peri/postnatal developmental studies, pregnant female rats were administered clozapine over the last third of pregnancy and until day 21 postpartum. Observations were made on fetuses at birth and during the postnatal period; the offspring were allowed to reach sexual maturity and mated. Clozapine caused a decrease in maternal body weight but had no effects on litter size or body weights of either F1 or F2 generations at doses up to 0.4 times the MRHD of 900 mg/day on a mg/m2 body surface area basis.

8.2 Lactation

PLLR conversion:

Risk Summary

Clozapine is present in human milk. There is one case report of sedation and a report of agranulocytosis in an infant exposed to clozapine through human milk (see Clinical Considerations). There is no information on the effects of clozapine on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for CLOZARIL and any potential adverse effects on the breastfed child from CLOZARIL or from the underlying maternal condition.

Clinical Considerations

Infants exposed to CLOZARIL should be monitored for excess sedation and neutropenia.

17 PCI/PI/MG (Patient Counseling Information/Patient Information/Medication Guide)

PATIENT COUNSELING INFORMATION

Additions and/or revisions underlined:

 

  • Pregnancy: Advise pregnant women to notify their healthcare provider if they become pregnant or intend to become pregnant during treatment with CLOZARIL. Advise patients that CLOZARIL may cause extrapyramidal and/or withdrawal symptoms (agitation, hypertonia, hypotonia, tremor, somnolence, respiratory distresss, and feeding disorder) in a neonate. Advise patients that there is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to CLOZARIL during pregnancy [see Use in Specific Populations 8.1)].

  • Lactation: Advise breastfeeding women using CLOZARIL to monitor infants for excess sedation and seek medical care if they notice this sign. Inform breastfeeding women using CLOZARIL that their healthcare provider will monitor infants for neutropenia [see Use in Specific Populations (8.2)].

               

05/19/2023 (SUPPL-103)

Approved Drug Label (PDF)

Boxed Warning

Orthostatic Hypotension, Bradycardia, Syncope

(Additions and/or revisions underlined)

Orthostatic hypotension, bradycardia, syncope, and cardiac arrest have occurred with CLOZARIL 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 CLOZARIL. Initiate treatment at 12.5 mg once or twice daily; titrate slowly; and use divided dosages to minimize risk. Use CLOZARIL 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, 2.5), Warnings and Precautions (5.3)].

5 Warnings and Precautions

5.2 Orthostatic Hypotension, Bradycardia, and Syncope

(Additions and/or revisions underlined)

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, at doses as low as 12.5 mg. These reactions can be fatal. The syndrome is consistent with neurally mediated reflex bradycardia (NMRB).

Treatment must begin at a maximum dose of 12.5 mg once daily or twice daily. The total daily dose can be increased in increments of 25 mg to 50 mg per day, if well-tolerated, to a target dose of 300 mg to 450 mg per day (administered in divided doses) by the end of 2 weeks. Subsequently, the dose can be increased weekly or twice weekly, in increments of up to 100 mg. The maximum dose is 900 mg per day. Use cautious titration and a divided dosage schedule to minimize the risk of serious cardiovascular reactions [see Dosage and Administration (2.2)]. Consider reducing the dose if hypotension occurs. When restarting CLOZARIL in patients who have had even a brief interruption in treatment with CLOZARIL, the dosage must be reduced. This is necessary to minimize the risk of hypotension, bradycardia, and syncope [see Dosage and Administration (2.5)].

17 PCI/PI/MG (Patient Counseling Information/Patient Information/Medication Guide)

17 PATIENT COUNSELING INFORMATION

(Additions and/or revisions underlined)

·       Orthostatic Hypotension, Bradycardia, and Syncope: Inform patients and caregivers about the risk of orthostatic hypotension and syncope, especially during the period of initial dose titration. Instruct them to strictly follow the clinician’s instructions for dosage and administration [see Dosage and Administraton (2.2, 2.5)]. Advise patients to consult their clinician immediately if they feel faint, lose consciousness or have signs or symptoms suggestive of bradycardia or arrhythmia [see Warnings and Precautions (5.3)].


12/19/2022 (SUPPL-101)

Approved Drug Label (PDF)

5 Warnings and Precautions

5.8 Gastrointestinal Hypomotility with Severe Complications

Additions and/or revisions underlined:

… In post marketing experience, reported effects range from constipation to paralytic ileus. Increased frequency of constipation and delayed diagnosis and treatment increased the risk of severe complications of gastrointestinal hypomotility, which can result in fecal impaction, megacolon, and intestinal obstruction, ischemia, infarction, perforation, ulceration or necrosis [see Adverse Reaction (6.2)]. These reactions have resulted in hospitalization, surgery, and death …

6 Adverse Reactions

6.2 Postmarketing Experience

Additions and/or revisions underlined:

Gastrointestinal System

Acute pancreatitis, dysphagia, salivary gland swelling, colitis, megacolon, and intestinal ischemia, infarction, perforation, ulceration or necrosis.

02/11/2021 (SUPPL-88)

Approved Drug Label (PDF)

6 Adverse Reactions

6.2 Postmarketing Experience

(Additions and/or revisions underlined)

The following adverse reactions have been identified during post-approval use of clozapine. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Central Nervous System

Delirium, EEG abnormal, myoclonus, paresthesia, possible cataplexy, status epilepticus, obsessive compulsive symptoms, restless leg syndrome, and post-discontinuation cholinergic rebound adverse reactions.

Cardiovascular System

Atrial or ventricular fibrillation, ventricular tachycardia, palpitations, QT interval prolongation, Torsades de Pointes, mitral valve incompetence associated with clozapine-related cardiomyopathy, myocardial infarction, cardiac arrest, myocarditis, and periorbital edema.

Vision Disorders Narrow-angle glaucoma.

Narrow-angle glaucoma.

Miscellaneous

Creatine phosphokinase elevation, hyperuricemia, hyponatremia, polyserositis, and weight loss.

04/14/2020 (SUPPL-95)

Approved Drug Label (PDF)

5 Warnings and Precautions

5.16 Anticholinergic Toxicity

(Additions and/or revisions underlined)

CLOZARIL has potent anticholinergic effects. Treatment with CLOZARIL can result in CNS and peripheral anticholinergic toxicity, especially at higher dosages, or in overdose situations. Use with caution in patients with a current diagnosis or prior history of constipation, urinary retention, clinically significant prostatic hypertrophy, or other conditions in which anticholinergic effects can lead to significant adverse reactions. When possible, avoid concomitant use, with other anticholinergic medications because the risk for anticholinergic toxicity or severe gastrointestinal adverse reactions is increased.

5.8 Gastrointestinal Hypomotility with Severe Complications

(Newly added subsection)

Severe gastrointestinal adverse reactions have occurred with the use of CLOZARIL, primarily due to its potent anticholinergic effects and resulting gastrointestinal hypomotility. In post marketing experience, reported effects range from constipation to paralytic ileus. Increased frequency of constipation and delayed diagnosis and treatment increased the risk of severe complications of gastrointestinal hypomotility, resulting in intestinal obstruction, fecal impaction, megacolon and intestinal ischemia or infarction. These reactions have resulted in hospitalization, surgery, and death. The risk of severe adverse reactions is further increased with anticholinergic medications (and other medications that decrease gastrointestinal peristalsis); therefore, concomitant use should be avoided when possible.

Prior to initiating CLOZARIL, screen for constipation and treat as necessary. Subjective symptoms of constipation may not accurately reflect the degree of gastrointestinal hypomotility in CLOZARIL treated patients. Therefore, reassess bowel function frequently with careful attention to any changes in the frequency or character of bowel movements, as well as signs and symptoms of complications of hypomotility (e.g., nausea, vomiting, abdominal distension, abdominal pain).

If constipation or gastrointestinal hypomotility are identified, monitor closely and treat promptly with appropriate laxatives, as necessary, to prevent severe complications. Consider prophylactic laxatives in high risk patients.

6 Adverse Reactions

(Additions and/or revisions underlined)

The following adverse reactions are discussed in more detail in other sections of the labeling:

  • Severe Neutropenia

  • Orthostatic Hypotension, Bradycardia, and Syncope

  • Falls

  • Seizures

  • Myocarditis, Cardiomyopathy, and Mitral Valve Incompetence

  • Increased Mortality in Elderly Patients with Dementia-Related Psychosis

  • Gastrointestinal Hypomotility with Severe Complications

  • Eosinophilia

  • QT Interval Prolongation

  • Metabolic Changes

  • Neuroleptic Malignant Syndrome

  • Hepatotoxicity

  • Fever

  • Pulmonary Embolism

  • Anticholinergic Toxicity

  • Interference with Cognitive and Motor Performance

  • Tardive Dyskinesia

  • Cerebrovascular Adverse Reactions

  • Recurrence of Psychosis and Cholinergic Rebound after Abrupt Discontinuation
6.2 Postmarketing Experience

(Additions and/or revisions underlined)

The following adverse reactions have been identified during post-approval use of clozapine. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Central Nervous System

Delirium, EEG abnormal, myoclonus, paresthesia, possible cataplexy, status epilepticus, obsessive compulsive symptoms, pleurothotonus, restless legs syndrome and post-discontinuation cholinergic rebound adverse reactions.

Cardiovascular System

Atrial or ventricular fibrillation, ventricular tachycardia, palpitations, QT interval prolongation, Torsades de Pointes, mitral valve incompetence associated with clozapine-related cardiomyopathy, myocardial infarction sometimes fatal, cardiac arrest, myocarditis sometimes fatal and periorbital edema.

Endocrine System

Pseudopheochromocytoma  

Gastrointestinal System

Acute pancreatitis, dysphagia, salivary gland swelling, colitis, megacolon, intestinal ischemia or infarction.

Hepatobiliary System

Cholestasis, hepatitis, jaundice, hepatotoxicity, hepatic steatosis, hepatic necrosis, hepatic fibrosis, hepatic cirrhosis, liver injury (hepatic, cholestatic, and mixed), and liver failure.

Immune System Disorders

Angioedema, leukocytoclastic vasculitis.

Urogenital System

Acute interstitial nephritis, nocturnal enuresis, priapism, renal failure, and retrograde ejaculation.

Skin and Subcutaneous Tissue Disorders

Hypersensitivity reactions: photosensitivity, vasculitis, erythema multiforme, skin pigmentation disorder, and Stevens- Johnson Syndrome.

Musculoskeletal System and Connective Tissue Disorders

Myasthenic syndrome, rhabdomyolysis, and systemic lupus erythematosus.

Respiratory System

Aspiration, pleural effusion, pneumonia, lower respiratory tract infection, sleep apnea.

Hemic and Lymphatic System

Mild, moderate, or severe leukopenia, agranulocytosis, granulocytopenia, WBC decreased, deep-vein thrombosis, elevated hemoglobin/hematocrit, erythrocyte sedimentation rate (ESR) increased, sepsis, thrombocytosis, and thrombocytopenia.

Vision Disorders

Narrow-angle glaucoma.  

Metabolic Changes

Obesity

Miscellaneous

Creatine phosphokinase elevation, hyperuricemia, hyponatremia, polyserositis and weight loss.

7 Drug Interactions

7.1 Potential for Other Drugs to Affect CLOZARIL

(Additions and/or revisions underlined)

Anticholinergic Drugs

Concomitant treatment with clozapine and other drugs with anticholinergic activity (e.g., benztropine, cyclobenzaprine, diphenhydramine) can increase the risk for anticholinergic toxicity and severe gastrointestinal adverse reactions related to hypomotility. Avoid concomitant use of CLOZARIL with anticholinergic drugs when possible.

17 PCI/PI/MG (Patient Counseling Information/Patient Information/Medication Guide)

PATIENT COUNSELING INFORMATION

(Additions and/or revisions underlined)

  • Gastrointestinal Hypomotility with Severe Complications: Educate patients and caregivers on the risks, prevention and treatment of clozapine-induced constipation, including medications to avoid when possible (e.g., drugs with anticholinergic activity). Encourage appropriate hydration, physical activity, and fiber intake and emphasize that prompt attention and treatment to the development of constipation or other gastrointestinal symptoms is critical in preventing severe complications. Advise patients and caregivers to contact their health care provider if they experience symptoms of constipation (e.g., difficulty passing stools, incomplete passage of stool, decreased bowel movement frequency) or other symptoms associated with gastrointestinal hypomotility (e.g., nausea, abdominal distension or pain, vomiting).

02/23/2017 (SUPPL-84)

Approved Drug Label (PDF)

5 Warnings and Precautions

5.12 Hepatotoxicity

(Newly added subsection)

Severe, life threatening, and in some cases fatal hepatotoxicity including hepatic failure, hepatic necrosis, and hepatitis have been reported in post marketing studies in patients treated with clozapine. Monitor for the appearance of signs and symptoms of hepatotoxicity such as fatigue, malaise, anorexia, nausea, jaundice, bilirubinemia, coagulopathy, and hepatic encephalopathy. Perform serum tests for liver injury and consider permanently discontinuing treatment if hepatitis or transaminase elevations combined with other systemic symptoms are due to clozapine.

5.4 Falls

(Newly added subsection)

Clozaril may cause somnolence, postural hypotension, motor and sensory instability, which may lead to falls and, consequently, fractures or other injuries. For patients with diseases, conditions, or medications that could exacerbate these effects, complete fall risk assessments when initiating antipsychotic treatment and recurrently for patients on long- term antipsychotic therapy.

6 Adverse Reactions

(Additions and/or revisions are underlined)

The following adverse reactions are discussed in more detail in other sections of the labeling:

•         Falls.

•         Hepatotoxicity.

01/26/2017 (SUPPL-81)

Approved Drug Label (PDF)

6 Adverse Reactions

6.2 Postmarketing Experience

(Additions and/or revisions are underlined)

Respiratory System

Aspiration, pleural effusion, pneumonia, lower respiratory tract infection, sleep apnea.

12/20/2016 (SUPPL-80)

Approved Drug Label (PDF)

Boxed Warning

(Additions and/or revisions are underlined in WARNING section title)

Myocarditis, Cardiomyopathy, and Mitral Valve Incompetence

Fatal myocarditis and cardiomyopathy have occurred with CLOZARIL treatment

5 Warnings and Precautions

5.5 Myocarditis, Cardiomyopathy, and Mitral Valve Incompetence

(Additions and/or revisions are underlined)

In patients who are diagnosed with cardiomyopathy while taking CLOZARIL mitral valve incompetence has been reported . These cases reported either mild or moderate mitral regurgitation on two-dimensional echocardiography In patients with suspected cardiomyopathy, consider a 2D-echo Doppler examination to identify mitral valve incompetence.

6 Adverse Reactions

(Additions and/or revisions are underlined)

The following adverse reactions are discussed in more detail in other sections of the labeling:

  • Myocarditis, Cardiomyopathy, and Mitral Valve Incompetence

6.2 Postmarketing Experience

(Additions and/or revisions are underlined)

Cardiovascular System

Atrial or ventricular fibrillation, ventricular tachycardia, palpitations, QT interval prolongation, Torsades de Pointes, mitral valve incompetence associated with clozapine-related cardiomyopthay, …


Gastrointestinal System

Acute pancreatitis, dysphagia, salivary gland swelling, colitis.

17 PCI/PI/MG (Patient Counseling Information/Patient Information/Medication Guide)

17 PATIENT COUNSELING INFORMATION

(Additions and/or revisions are underlined)

  • Severe Neutropenia:

…Provide patients (and caregivers) with website information and the telephone number on how to obtain the product (www.clozapinerems.com or 1-844-267-8678)

  • Nursing: Advise patients and caregivers that the patient should not breastfeed…