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.
Management Of OverdosageFor the most up-to-date information on the management of VERSACLOZ overdosage, contact a certified Regional Poison Control Center (1-800-222-1222). Telephone numbers of certified Regional Poison Control Centers are listed in the Physician's Desk Reference®, a registered trademark of PDR Network. Establish and maintain an airway; ensure adequate oxygenation and ventilation. Monitor cardiac status and vital signs. Use general symptomatic and supportive measures. There are no specific antidotes for VERSACLOZ.
In managing overdosage, consider the possibility of multiple-drug involvement.
VERSACLOZ is contraindicated in patients with a history of serious hypersensitivity to clozapine (e.g., photosensitivity, vasculitis, erythema multiforme, or Stevens-Johnson Syndrome) or any other component of VERSACLOZ.
The following adverse reactions are discussed in more detail in other sections of the labeling:
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, Chlorpromazinecontrolled 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™ 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 |
Hypokinesia/Akinesia | 4 |
Agitation | 4 |
Seizures (convulsions) | 3† |
Rigidity | 3 |
Akathisia | 3 |
Confusion | 3 |
Fatigue | 2 |
Insomnia | 2 |
Cardiovascular | |
Tachycardia | 25† |
Hypotension | 9 |
Hypertension | 4 |
Gastrointestinal | |
Constipation | 14 |
Nausea | 5 |
Abdominal Discomfort/Heartburn | 4 |
Nausea/Vomiting | 3 |
Vomiting | 3 |
Diarrhea | 2 |
Urogenital | |
Urinary Abnormalities | 2 |
Autonomic Nervous System | |
Salivation | 31 |
Sweating | 6 |
Dry Mouth | 6 |
Visual Disturbances | 5 |
Skin | |
Rash | 2 |
Hemic/Lymphatic | |
Leukopenia/Decreased WBC/Neutropenia | 3 |
Miscellaneous | |
Fever | 5 |
Weight Gain | 4 |
† Rate based on population of approximately 1700 exposed during premarket clinical evaluation of clozapine. |
Table 11 summarizes the most commonly reported adverse reactions ( > 10% of the clozapine or olanzapine group) in the InterSePT™ Study. This was an adequate and well-controlled, two-year study evaluating the efficacy of clozapine relative to olanzapine in reducing the risk of suicidal behavior in patients with schizophrenia or schizoaffective disorder. The rates are not adjusted for duration of exposure.
Table 11: Incidence of Adverse Reactions in Patients
Treated with Clozapine or Olanzapine in the InterSePT™ Study ( ≥ 10% in the
clozapine or olanzapine group)
Adverse Reactions | Clozapine N=479 % Reporting |
Olanzapine N=477 % Reporting |
Salivary hypersecretion | 48% | 6% |
Somnolence | 46% | 25% |
Weight increased | 31% | 56% |
Dizziness (excluding vertigo) | 27% | 12% |
Constipation | 25% | 10% |
Insomnia. | 20% | 33% |
Nausea | 17% | 10% |
Vomiting | 17% | 9% |
Dyspepsia | 14% | 8% |
Class effect: Symptoms of dystonia, prolonged abnormal contractions of muscle groups, may occur in susceptible individuals during the first few days of treatment. Dystonic symptoms include: spasm of the neck muscles, sometimes progressing to tightness of the throat, swallowing difficulty, difficulty breathing, and/or protrusion of the tongue. While these symptoms can occur at low doses, they occur more frequently and with greater severity with high potency and at higher doses of first generation antipsychotic drugs. An elevated risk of acute dystonia is observed in males and younger age groups.
Postmarketing ExperienceThe 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 SystemDelirium, EEG abnormal, myoclonus, paresthesia, possible cataplexy, status epilepticus, obsessive compulsive symptoms, and post-discontinuation cholinergic rebound adverse reactions.
Cardiovascular SystemAtrial or ventricular fibrillation, ventricular tachycardia, QT interval prolongation, Torsades de Pointes, myocardial infarction, cardiac arrest, and periorbital edema.
Endocrine SystemPseudopheochromocytoma.
Gastrointestinal SystemAcute pancreatitis, dysphagia, salivary gland swelling.
Hepatobiliary SystemCholestasis, hepatitis, jaundice, hepatotoxicity, hepatic steatosis, hepatic necrosis, hepatic fibrosis, hepatic cirrhosis, liver injury (hepatic, cholestatic, and mixed), and liver failure.
Immune System DisordersAngioedema, leukocytoclastic vasculitis.
Urogenital SystemAcute interstitial nephritis, nocturnal enuresis, priapism, and renal failure.
Skin and Subcutaneous Tissue DisordersHypersensitivity reactions: photosensitivity, vasculitis, erythema multiforme, skin pigmentation disorder, and Stevens-Johnson Syndrome.
Musculoskeletal System and Connective Tissue DisordersMyasthenic syndrome, rhabdomyolysis, and systemic lupus erythematosus.
Respiratory SystemAspiration, pleural effusion, pneumonia, lower respiratory tract infection.
Hemic and Lymphatic SystemMild, moderate, or severe leukopenia, agranulocytosis, granulocytopenia, WBC decreased, deep vein thrombosis, elevated hemoglobin/hematocrit, erythrocyte sedimentation rate (ESR) increased, sepsis, thrombocytosis, and thrombocytopenia.
Vision DisordersNarrow-angle glaucoma.
MiscellaneousCreatine phosphokinase elevation, hyperuricemia, hyponatremia, and weight loss.
VERSACLOZ is 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, VERSACLOZ should be used only in patients who have failed to respond adequately to standard antipsychotic treatment.
The effectiveness of clozapine in treatment-resistant schizophrenia was demonstrated in a 6-week, randomized, double-blind, active-controlled study comparing clozapine and chlorpromazine in patients who had failed other antipsychotics.
Reduction In The Risk Of Recurrent Suicidal Behavior In Schizophrenia Or Schizoaffective DisorderVERSACLOZ is 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 in reducing the risk of recurrent suicidal behavior was demonstrated over a two-year treatment period in the InterSePT™ trial.
Clozapine demonstrated binding affinity to the following receptors: histamine H1 (Ki 1.1 nM), adrenergic α1A (Ki 1.6 nM), serotonin 5-HT6 (Ki 4 nM), serotonin 5-HT2A (Ki 5.4 nM), muscarinic M1 (Ki 6.2 nM), serotonin 5-HT7 (Ki 6.3 nM), serotonin 5-HT2C (Ki 9.4 nM), dopamine D4 (Ki 24 nM), adrenergic α2A (Ki 90 nM), serotonin 5-HT3 (Ki 95 nM), serotonin 5HT1A (Ki 120 nM), dopamine D2 (Ki 160 nM), dopamine D1 (Ki 270 nM), dopamine D5 (Ki 454 nM), and dopamine D3 (Ki 555 nM).
Clozapine causes little or no prolactin elevation.
Clinical electroencephalogram (EEG) studies demonstrated that clozapine increases delta and theta activity and slows dominant alpha frequencies. Enhanced synchronization occurs. Sharp wave activity and spike and wave complexes may also develop. Patients have reported an intensification of dream activity during clozapine therapy. REM sleep was found to be increased to 85% of the total sleep time. In these patients, the onset of REM sleep occurred almost immediately after falling asleep.
In man, clozapine tablets (25 mg and 100 mg) are equally bioavailable relative to a clozapine solution. VERSACLOZ Oral Suspension is bioequivalent to clozapine marketed tablets.
Following oral administration of 100 mg to 800 mg VERSACLOZ, once daily, the average steady-state peak plasma concentration was 275 ng/mL (range: 105-723 ng/mL), occurring at the average of 2.2 hours (range: 1 to 3.5 hours) after dosing. The average minimum concentration at steady-state was 75 ng/mL (range: 11-198 ng/mL).
When VERSACLOZ was administered after a high fat meal there was no effect on the AUCss or Cmin,ss, however Cmax was reduced about 20%, and there was a slight delay in Tmax of 0.5 hour from a median Tmax of 2.0 hours under fasted conditions to 2.5 hours under fed conditions. The decrease in Cmax is not considered clinically relevant. Therefore VERSACLOZ may be taken without regard to meals.
DistributionClozapine is approximately 97% bound to serum proteins. The interaction between clozapine and other highly protein-bound drugs has not been fully evaluated but may be important..
Metabolism And ExcretionVERSACLOZ is almost completely metabolized prior to excretion, and only trace amounts of unchanged drug are detected in the urine and feces. VERSACLOZ is a substrate for many cytochrome P450 isozymes, in particular CYP1A2, CYP2D6, and CYP3A4. Approximately 50% of the administered dose is excreted in the urine and 30% in the feces. The demethylated, hydroxylated, and N-oxide derivatives are components in both urine and feces. Pharmacological testing has shown the desmethyl metabolite (norclozapine) to have only limited activity, while the hydroxylated and N-oxide derivatives were inactive. The mean elimination half-life of clozapine after a single 75 mg dose was 8 hours (range: 4-12 hours), compared to a mean elimination half-life of 12 hours (range: 4-66 hours), after achieving steady-state with 100 mg twice daily dosing.
A comparison of single-dose and multiple-dose administration of clozapine demonstrated that the elimination half-life increased significantly after multiple dosing relative to that after single-dose administration, suggesting the possibility of concentration-dependent pharmacokinetics. However, at steady-state, approximately dose-proportional changes with respect to AUC (area under the curve), peak, and minimum clozapine plasma concentrations were observed after administration of 37.5, 75, and 150 mg twice daily.
Pregnancy Category B.
Risk SummaryThere are no adequate or well-controlled studies of clozapine in pregnant women.
Reproduction studies have been performed in rats and rabbits at doses up to 0.4 and 0.9 times, respectively, the maximum recommended human dose (MRHD) of 900 mg/day on a mg/m² body surface area basis. The studies revealed no evidence of impaired fertility or harm to the fetus due to clozapine. Because animal reproduction studies are not always predictive of human response, VERSACLOZ should be used during pregnancy only if clearly needed.
Clinical ConsiderationsConsider the risk of exacerbation of psychosis when discontinuing or changing treatment with antipsychotic medications during pregnancy and postpartum. Consider early screening for gestational diabetes for patients treated with antipsychotic medications. Neonates exposed to antipsychotic drugs during the third trimester of pregnancy are at risk for extrapyramidal and/or withdrawal symptoms following delivery. Monitor neonates for symptoms of agitation, hypertonia, hypotonia, tremor, somnolence, respiratory distress, and feeding difficulties. The severity of complications can vary from self-limited symptoms to some neonates requiring intensive care unit support and prolonged hospitalization.
Animal DataIn 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.
VERSACLOZ is available as a free-flowing yellow oral suspension. Each mL contains 50 mg of clozapine.
Oral SuspensionFree-flowing, yellow suspension (50 mg/mL) in amber bottle containing 100 mL. Each box contains 1 x 1 mL oral syringe, 1 x 9 mL oral syringe and 1 bottle adaptor.
NDC No. 18860-121-01
Storage And HandlingStore VERSACLOZ at or below 25°C (77°F). Do not refrigerate or freeze. Protect from light. Shake well for 10 seconds before use.
The suspension is stable for 100 days after initial bottle opening.
Keep out of reach of children.
Distributed by: Jazz Pharmaceuticals, Inc., Palo Alto, CA 94304. Revised: Feb 2017
Included as part of the PRECAUTIONS section.
PRECAUTIONS Severe Neutropenia BackgroundVERSACLOZ can cause neutropenia (a low absolute neutrophil count [ANC]), defined as a reduction below pre-treatment normal levels of blood neutrophils. The ANC is usually available as a component of the complete blood count (CBC), including differential, and is more relevant to drug-induced neutropenia than is the white blood cell (WBC) count. The ANC may also be calculated using the following formula: ANC equals the Total WBC count multiplied by the total percentage of neutrophils obtained from the differential (neutrophil “segs” plus neutrophil “bands”). Other granulocytes (basophils and eosinophils) contribute minimally to neutropenia and their measurement is not necessary. Neutropenia may be mild, moderate, or severe (see Tables 2 and 3). To improve and standardize understanding, “severe neutropenia” replaces the previous terms severe leukopenia, severe granulocytopenia, or agranulocytosis.
Severe neutropenia, ANC less than ( < ) 500/μL, occurs in a small percentage of patients taking VERSACLOZ and is associated with an increase in the risk of serious and potentially fatal infections. Risk of neutropenia appears greatest during the first 18 weeks on treatment and then declines. The mechanism by which VERSACLOZ causes neutropenia is unknown and is not dose-dependent.
Two separate management algorithms are provided below, the first for patients in the general population, and the second for patients identified to have baseline neutropenia.
VERSACLOZ Treatment And Monitoring In The General Patient Population (see Table 2)Obtain a CBC, including the ANC value, prior to initiating treatment with VERSACLOZ to ensure the presence of a normal baseline neutrophil count (equal to or greater than 1500/μL) and to permit later comparisons. Patients in the general population with an ANC equal to or greater than ( ≥ )1500/μL are considered within normal range (Table 2) and are eligible to initiate treatment. Weekly ANC monitoring is required for all patients during the first 6 months of treatment. If a patient's ANC remains equal to or greater than 1500/μL for the first 6 months of treatment, monitoring frequency may be reduced to every 2 weeks for the next 6 months. If the ANC remains equal to or greater than 1500/μL for the second 6 months of continuous therapy, ANC monitoring frequency may be reduced to once every 4 weeks thereafter.
Table 2: VERSACLOZ Treatment Recommendations Based on
Absolute Neutrophil Count (ANC) Monitoring for the General Patient Population
ANC Level | VERSACLOZ Treatment Recommendations | ANC Monitoring |
Normal range ( ≥ 1500/μL) |
|
|
|
|
|
Mild Neutropenia (1000 to 1499/μL)* |
|
|
Moderate Neutropenia (500 to 999/μL)* |
|
|
Severe Neutropenia (less than 500/μL)* |
|
|
* Confirm all initial reports of ANC less than 1500/μL
with a repeat ANC measurement within 24 hours ** If clinically appropriate |
Benign ethnic neutropenia (BEN) is a condition observed in certain ethnic groups whose average ANC values are lower than “standard” laboratory ranges for neutrophils. It is most commonly observed in individuals of African descent (approximate prevalence of 25-50%), some Middle Eastern ethnic groups, and in other non-Caucasian ethnic groups with darker skin. BEN is more common in men. Patients with BEN have normal hematopoietic stem-cell number and myeloid maturation, are healthy, and do not suffer from repeated or severe infections. They are not at increased risk for developing VERSACLOZ-induced neutropenia. Additional evaluation may be needed to determine if baseline neutropenia is due to BEN. Consider hematology consultation before initiating or during VERSACLOZ treatment as necessary.
Patients with BEN require a different ANC algorithm for VERSACLOZ management due to their lower baseline ANC levels. Table 3 provides guidelines for managing VERSACLOZ treatment and ANC monitoring in patients with BEN.
Table 3: Patients with
Benign Ethnic Neutropenia (BEN); VERSACLOZ Treatment Recommendations Based on
Absolute Neutrophil Count (ANC) Monitoring
ANC Level | Treatment Recommendations | ANC Monitoring |
Normal BEN Range (Established ANC baseline ≥ 1000/μL ) |
|
|
|
|
|
BEN Neutropenia (500 to 999/μL)* |
|
|
BEN Severe Neutropenia (less than 500/μL)* |
|
|
* Confirm all initial reports
of ANC less than 1500/μL with a repeat ANC measurement within 24 hours ** If clinically appropriate |
It is unclear if concurrent use of other drugs known to cause neutropenia increases the risk or severity of VERSACLOZ-induced neutropenia. There is no strong scientific rationale to avoid VERSACLOZ treatment in patients concurrently treated with these drugs. If VERSACLOZ is used concurrently with an agent known to cause neutropenia (e.g., some chemotherapeutic agents), consider monitoring patients more closely than the treatment guidelines provided in Tables 2 and 3. Consult with the treating oncologist in patients receiving concomitant chemotherapy.
Clozapine REMS ProgramVERSACLOZ is only available through a restricted program under a REMS called the Clozapine REMS Program because of the risk of severe neutropenia.
Notable requirements of the Clozapine REMS Program include:
Further information is available at www.clozapinerems.com or 1-844-267-8678.
Orthostatic Hypotension, Bradycardia, And SyncopeHypotension, 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. Consider reducing the dose if hypotension occurs. When restarting patients who have had even a brief interval off VERSACLOZ (i.e., 2 days or more since the last dose), re-initiate treatment at 12.5 mg once daily or twice daily.
Use VERSACLOZ cautiously in patients with cardiovascular disease (history of myocardial infarction or ischemia, heart failure, or conduction abnormalities), cerebrovascular disease, and conditions which would predispose patients to hypotension (e.g., concomitant use of antihypertensives, dehydration and hypovolemia).
FallsVERSACLOZ may cause somnolence, postural hypotension, and 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 treatment.
SeizuresSeizure has been estimated to occur in association with clozapine use at a cumulative incidence at one year of approximately 5%, based on the occurrence of one or more seizures in 61 of 1743 patients exposed to clozapine during its clinical testing prior to domestic marketing (i.e., a crude rate of 3.5%). The risk of seizure is dose-related. Initiate treatment with a low dose (12.5 mg), titrate slowly, and use divided dosing.
Use caution when administering VERSACLOZ to patients with a history of seizures or other predisposing risk factors for seizure (e.g., head trauma or other CNS pathology, use of medications that lower the seizure threshold, or alcohol abuse). Because of the substantial risk of seizure associated with VERSACLOZ use, caution patients about engaging in any activity where sudden loss of consciousness could cause serious risk to themselves or others (e.g., driving an automobile, operating complex machinery, swimming, climbing).
Myocarditis And CardiomyopathyMyocarditis and cardiomyopathy have occurred with the use of clozapine. These reactions can be fatal. Discontinue VERSACLOZ 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 VERSACLOZ. However, if the benefit of VERSACLOZ treatment is judged to outweigh the potential risks of recurrent myocarditis or cardiomyopathy, the clinician may consider rechallenge with VERSACLOZ in consultation with a cardiologist, after a complete cardiac evaluation, and under close monitoring.
Consider the possibility of myocarditis or cardiomyopathy in patients receiving VERSACLOZ who present with chest pain, dyspnea, persistent tachycardia at rest, palpitations, fever, flu-like symptoms, hypotension, other signs or symptoms of heart failure, or electrocardiographic findings (low voltages, ST-T abnormalities, arrhythmias, right axis deviation, and poor R wave progression). Myocarditis most frequently presents within the first two months of clozapine treatment. Symptoms of cardiomyopathy generally occur later than clozapine-associated myocarditis and usually after 8 weeks of treatment. However, myocarditis and cardiomyopathy can occur at any period during treatment with VERSACLOZ. It is common for nonspecific flu-like symptoms such as malaise, myalgia, pleuritic chest pain, and low-grade fevers to precede more overt signs of heart failure. Typical laboratory findings include elevated troponin I or T, elevated creatinine kinase-MB, peripheral eosinophilia, and elevated C-reactive protein (CRP). Chest roentgenogram may demonstrate cardiac silhouette enlargement, and cardiac imaging (echocardiogram, radionucleotide studies, or cardiac catheterization) may reveal evidence of left ventricular dysfunction.
Increased Mortality In Elderly Patients With Dementia-Related PsychosisElderly patients with dementia-related psychosis treated with antipsychotic drugs are at an increased risk of death. Analyses of 17 placebo-controlled trials (modal duration of 10 weeks), largely in patients taking atypical antipsychotic drugs, revealed a risk of death in drug-treated patients of between 1.6 to 1.7 times the risk of death in placebo-treated patients. Over the course of a typical 10-week controlled trial, the rate of death in drug-treated patients was about 4.5%, compared to a rate of about 2.6% in the placebo group. Although the causes of death were varied, most of the deaths appeared to be either cardiovascular (e.g., heart failure, sudden death) or infectious (e.g., pneumonia) in nature. Observational studies suggest that, similar to atypical antipsychotic drugs, treatment with conventional antipsychotic drugs may increase mortality in this population. The extent to which the findings of increased mortality in observational studies may be attributed to the antipsychotic drug as opposed to some characteristic(s) of the patients is not clear. VERSACLOZ is not approved for the treatment of patients with dementia-related psychosis.
EosinophiliaEosinophilia, defined as a blood eosinophil count of greater than 700/μL, has occurred with clozapine treatment. In clinical trials, approximately 1% of patients developed eosinophilia. Clozapine-related eosinophilia usually occurs during the first month of treatment. In some patients, it has been associated with myocarditis, pancreatitis, hepatitis, colitis, and nephritis. Such organ involvement could be consistent with a drug reaction with eosinophilia and systemic symptoms syndrome (DRESS), also known as drug induced hypersensitivity syndrome (DIHS). If eosinophilia develops during VERSACLOZ treatment, evaluate promptly for signs and symptoms of systemic reactions, such as rash or other allergic symptoms, myocarditis, or other organ-specific disease associated with eosinophilia. If clozapine-related systemic disease is suspected, discontinue VERSACLOZ immediately.
If a cause of eosinophilia unrelated to clozapine is identified (e.g., asthma, allergies, collagen vascular disease, parasitic infections, and specific neoplasms), treat the underlying cause and continue VERSACLOZ.
Clozapine-related eosinophilia has also occurred in the absence of organ involvement and can resolve without intervention. There are reports of successful rechallenge after discontinuation of clozapine, without recurrence of eosinophilia. In the absence of organ involvement, continue VERSACLOZ under careful monitoring. If the total eosinophil count continues to increase over several weeks in the absence of systemic disease, the decision to interrupt VERSACLOZ therapy and rechallenge after the eosinophil count decreases should be based on the overall clinical assessment, in consultation with an internist or hematologist.
QT Interval ProlongationQT prolongation, Torsades de Pointes and other life-threatening ventricular arrhythmias, cardiac arrest, and sudden death have occurred with clozapine treatment. When prescribing VERSACLOZ, consider the presence of additional risk factors for QT prolongation and serious cardiovascular reactions. Conditions that increase these risks include the following: history of QT prolongation, long QT syndrome, family history of long QT syndrome or sudden cardiac death, significant cardiac arrhythmia, recent myocardial infarction, uncompensated heart failure, treatment with other medications that cause QT prolongation, treatment with medications that inhibit the metabolism of VERSACLOZ, and electrolyte abnormalities.
Prior to initiating treatment with VERSACLOZ, perform a careful physical examination, medical history, and concomitant medication history. Consider obtaining a baseline ECG and serum chemistry panel. Correct electrolyte abnormalities. Discontinue VERSACLOZ if the QTc interval exceeds 500 msec. If patients experience symptoms consistent with Torsades de Pointes or other arrhythmias, (e.g., syncope, presyncope, dizziness, or palpitations), obtain a cardiac evaluation and discontinue VERSACLOZ.
Use caution when administering concomitant medications that prolong the QT interval or inhibit the metabolism of VERSACLOZ. Drugs that cause QT prolongation include: specific antipsychotics (e.g., ziprasidone, iloperidone, chlorpromazine, thioridazine, mesoridazine, droperidol, pimozide), specific antibiotics (e.g., erythromycin, gatifloxacin, moxifloxacin, sparfloxacin), Class 1A antiarrhythmic medications (e.g., quinidine, procainamide) or Class III antiarrhythmic (e.g., amiodarone, sotalol), and others (e.g., pentamidine, levomethadyl acetate, methadone, halofantrine, mefloquine, dolasetron mesylate, probucol or tacrolimus). VERSACLOZ is primarily metabolized by CYP isoenzymes 1A2, 2D6, and 3A4. Concomitant treatment with inhibitors of these enzymes can increase the concentration of VERSACLOZ.
Hypokalemia and hypomagnesemia increase the risk of QT prolongation. Hypokalemia can result from diuretic therapy, diarrhea, and other causes. Use caution when treating patients at risk for significant electrolyte disturbance, particularly hypokalemia. Obtain baseline measurements of serum potassium and magnesium levels, and periodically monitor electrolytes. Correct electrolyte abnormalities before initiating treatment with VERSACLOZ.
Metabolic ChangesAtypical antipsychotic drugs, including VERSACLOZ, have been associated with metabolic changes that can increase cardiovascular and cerebrovascular risk. These metabolic changes include hyperglycemia, dyslipidemia, and body weight gain. While atypical antipsychotic drugs may produce some metabolic changes, each drug in the class has its own specific risk profile.
Hyperglycemia And Diabetes MellitusHyperglycemia, in some cases extreme and associated with ketoacidosis or hyperosmolar coma or death, has been reported in patients treated with atypical antipsychotics including VERSACLOZ. Assessment of the relationship between atypical antipsychotic use and glucose abnormalities is complicated by the possibility of an increased background risk of diabetes mellitus in patients with schizophrenia and the increasing incidence of diabetes mellitus in the general population. Given these confounders, the relationship between atypical antipsychotic use and hyperglycemia-related adverse reactions is not completely understood. However, epidemiological studies suggest an increased risk of treatment-emergent, hyperglycemia-related adverse reactions in patients treated with the atypical antipsychotics. Precise risk estimates for hyperglycemia-related adverse reactions in patients treated with atypical antipsychotics are not available.
Patients with an established diagnosis of diabetes mellitus who are started on VERSACLOZ should be monitored regularly for worsening of glucose control. Patients with risk factors for diabetes mellitus (e.g., obesity, family history of diabetes) who are starting treatment with atypical antipsychotics should undergo fasting blood glucose testing at the beginning of treatment and periodically during treatment. Any patient treated with atypical antipsychotics should be monitored for symptoms of hyperglycemia including polydipsia, polyuria, polyphagia, and weakness. Patients who develop symptoms of hyperglycemia during treatment with atypical antipsychotics should undergo fasting blood glucose testing. In some cases, hyperglycemia has resolved when the atypical antipsychotic was discontinued; however, some patients required continuation of anti-diabetic treatment despite discontinuation of the suspect drug.
In a pooled data analysis of 8 studies in adult subjects with schizophrenia, the mean changes in fasting glucose concentration in the clozapine and chlorpromazine groups were +11 mg/dL and +4 mg/dL respectively. A higher proportion of the clozapine group demonstrated categorical increases from baseline in fasting glucose concentrations, compared to the chlorpromazine group (Table 4). The clozapine doses were 100-900 mg per day (mean modal dose: 512 mg per day). The maximum chlorpromazine dose was 1800 mg per day (mean modal dose: 1029 mg per day). The median duration of exposure was 42 days for clozapine and chlorpromazine.
Table 4: Categorical Changes in Fasting Glucose Level
in Studies in Adult Subjects with Schizophrenia
Laboratory Parameter | Category Change (at least once) from baseline | Treatment Arm | N | n (%) |
Fasting Glucose | Normal ( < 100 mg/dL) to High ( ≥ 126 mg/dL) | Clozapine | 198 | 53 (27) |
Chlorpromazine | 135 | 14 (10) | ||
Borderline (100 to 125 mg/dL) to High ( ≥ 126 mg/dL) | Clozapine | 57 | 24 (42) | |
Chlorpromazine | 43 | 12 (28) |
Undesirable alterations in lipids have occurred in patients treated with atypical antipsychotics, including VERSACLOZ. Clinical monitoring, including baseline and periodic follow-up lipid evaluations in patients using VERSACLOZ, is recommended.
In a pooled data analysis of 10 studies in adult subjects with schizophrenia, clozapine treatment was associated with increases in serum total cholesterol. No data were collected on LDL and HDL cholesterol. The mean increase in total cholesterol was 13 mg/dL in the clozapine group and 15 mg/dL in the chlorpromazine group. In a pooled data analysis of 2 studies in adult subjects with schizophrenia, clozapine treatment was associated with increases in fasting serum triglyceride. The mean increase in fasting triglyceride was 71 mg/dL (54%) in the clozapine group and 39 mg/dL (35%) in the chlorpromazine group (Table 5). In addition, clozapine treatment was associated with categorical increases in serum total cholesterol and triglyceride, as illustrated in Table 6. The proportion of patients with categorical increases in total cholesterol or fasting triglyceride increased with the duration of exposure. The median duration of clozapine and chlorpromazine exposure was 45 days and 38 days, respectively. The clozapine dose range was 100 mg to 900 mg daily; the maximum chlorpromazine dose was 1800 mg daily.
Table 5: Mean Changes in Total Cholesterol and
Triglyceride Concentration in Studies in Adult Subjects with Schizophrenia
Treatment Arm | Baseline total cholesterol concentration (mg/dL) | Change from baseline mg/dL (%) |
Clozapine (N=334) | 184 | +13 (7) |
Chlorpromazine (N=185) | 182 | +15 (8) |
Baseline triglyceride concentration (mg/dL) | Change from baseline mg/dL (%) | |
Clozapine (N=6) | 130 | +71 (54) |
Chlorpromazine (N=7) | 110 | +39 (35) |
Table 6: Categorical Changes
in Lipid Concentrations in Studies in Adult Subjects with Schizophrenia
Laboratory Parameter | Category Change (at least once) from Baseline | Treatment Arm | N | n (%) |
Total Cholesterol (random or fasting) | Increase by ≥ 40 mg/dL | Clozapine | 334 | 111 (33) |
Chlorpromazine | 185 | 46 (25) | ||
Normal ( < 200 mg/dL) to High ( ≥ 240 mg/dL) | Clozapine | 222 | 18 (8) | |
Chlorpromazine | 132 | 3 (2) | ||
Borderline (200 - 239 mg/dL) to High ( ≥ 240 mg/dL) | Clozapine | 79 | 30 (38) | |
Chlorpromazine | 34 | 14 (41) | ||
Triglycerides (fasting) | Increase by ≥ 50 mg/dL | Clozapine | 6 | 3 (50) |
Chlorpromazine | 7 | 3 (43) | ||
Normal ( < 150 mg/dL) to High ( ≥ 200 mg/dL) | Clozapine | 4 | 0 (0) | |
Chlorpromazine | 6 | 2 (33) | ||
Borderline ( ≥ 150 mg/dL and < 200 mg/dL) to High ( ≥ 200 mg/dL) | Clozapine | 1 | 1 (100) | |
Chlorpromazine | 1 | 0 (0) |
Weight gain has occurred with the use of antipsychotics, including VERSACLOZ. Monitor weight during treatment with VERSACLOZ. Table 7 summarizes the data on weight gain by the duration of exposure pooled from 11 studies with clozapine and active comparators. The median duration of exposure was 609, 728, and 42 days, in the clozapine, olanzapine, and chlorpromazine group, respectively.
Table 7: Mean Change in Body
Weight (kg) by duration of exposure from studies in adult subjects with schizophrenia
Metabolic parameter | Exposure duration | Clozapine (N=669) |
Olanzapine (N=442) |
Chlorpromazine (N=155) |
|||
n | Mean | n | Mean | n | Mean | ||
Weight change from baseline | 2 weeks (Day 11 - 17) | 6 | +0.9 | 3 | +0.7 | 2 | -0.5 |
4 weeks (Day 21 - 35) | 23 | +0.7 | 8 | +0.8 | 17 | +0.6 | |
8 weeks (Day 49 - 63) | 12 | +1.9 | 13 | +1.8 | 16 | +0.9 | |
12 weeks (Day 70 - 98) | 17 | +2.8 | 5 | +3.1 |
Prior to initiating treatment with VERSACLOZ, a baseline ANC must be obtained. The baseline ANC must be at least 1500/μL for the general population, and at least 1000/μL for patients with documented Benign Ethnic Neutropenia (BEN). To continue treatment, the ANC must be monitored regularly.
Dosing InformationThe starting dose is 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 achieve 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 once weekly or twice weekly, in increments of up to 100 mg. The maximum dose is 900 mg per day. To minimize the risk of orthostatic hypotension, bradycardia, and syncope, it is necessary to use this low starting dose, gradual titration schedule, and divided dosages.
Important Administration InstructionsVERSACLOZ Oral Suspension is administered to the mouth by the oral syringes provided (1 mL or 9 mL). After shaking the bottle for 10 seconds prior to each use, the syringe adaptor is pressed on top of the bottle. The oral syringe (1 mL or 9 mL) is filled with air, and inserted into the adaptor. The air is dispelled into the bottle and then the bottle is turned upside down. The prescribed amount of the suspension is drawn from the bottle and dispensed directly to the mouth. The prescribed dose should be administered immediately after it is prepared. Do not draw a dose and store it in the syringe for later use. After use, the oral syringe may be washed with warm water and dried for next use. The bottle may be closed with the same cap without removing the bottle adaptor. Educate patients and caregivers on the steps to administer VERSACLOZ as described in the Patient Instructions for Use.
VERSACLOZ can be taken with or without food.
Maintenance TreatmentGenerally, patients responding to VERSACLOZ should continue maintenance treatment on their effective dose beyond the acute episode.
Discontinuation Of TreatmentMethod of treatment discontinuation will vary depending on the patient's last ANC:
When restarting VERSACLOZ in patients who have discontinued VERSACLOZ (i.e., 2 days or more since the last dose), re-initiate with 12.5 mg once daily or twice daily. This is necessary to minimize the risk of hypotension, bradycardia, and syncope. If that dose is well tolerated, the dose may be increased to the previously therapeutic dose more quickly than recommended for initial treatment.
Dosage Adjustments With Concomitant Use Of CYP1A2, CYP2D6, CYP3A4 Inhibitors Or CYP1A2, CYP3A4 InducersDose adjustments may be necessary in patients with concomitant use of: strong CYP1A2 inhibitors (e.g., fluvoxamine, ciprofloxacin, or enoxacin); moderate or weak CYP1A2 inhibitors (e.g., oral contraceptives, or caffeine); CYP2D6 or CYP3A4 inhibitors (e.g., cimetidine, escitalopram, erythromycin, paroxetine, bupropion, fluoxetine, quinidine, duloxetine, terbinafine, or sertraline); CYP3A4 inducers (e.g., phenytoin, carbamazepine, St. John's wort, and rifampin); or CYP1A2 inducers (e.g., tobacco smoking) (Table 1).
Table 1: Dose Adjustment in Patients Taking
Concomitant Medications
Co-medications | Scenarios | ||
Initiating VERSACLOZ while taking a co-medication | Adding a co-medication while taking VERSACLOZ | Discontinuing a co-medication while continuing VERSACLOZ | |
Strong CYP1A2 Inhibitors | Use one third of the VERSACLOZ dose. | Increase VERSACLOZ dose based on clinical response. | |
Moderate or Weak CYP1A2 Inhibitors | Monitor for adverse reactions. Consider reducing the VERSACLOZ dose if necessary. | Monitor for lack of effectiveness. Consider increasing VERSACLOZ dose if necessary. | |
CYP2D6 or CYP3A4 Inhibitors | |||
Strong CYP3A4 Inducers | Concomitant use is not recommended. However, if the inducer is necessary, it may be necessary to increase the VERSACLOZ dose. Monitor for decreased effectiveness. | Reduce VERSACLOZ dose based on clinical response. | |
Moderate or weak CYP1A2 or CYP3A4 Inducers | Monitor for decreased effectiveness. Consider increasing the VERSACLOZ dose if necessary. | Monitor for adverse reactions. Consider reducing the VERSACLOZ dose if necessary. |
It may be necessary to reduce the VERSACLOZ dose in patients with significant renal or hepatic impairment, or in CYP2D6 poor metabolizers.
The following adverse reactions are discussed in more detail in other sections of the labeling:
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, Chlorpromazinecontrolled 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™ 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 |
Hypokinesia/Akinesia | 4 |
Agitation | 4 |
Seizures (convulsions) | 3† |
Rigidity | 3 |
Akathisia | 3 |
Confusion | 3 |
Fatigue | 2 |
Insomnia | 2 |
Cardiovascular | |
Tachycardia | 25† |
Hypotension | 9 |
Hypertension | 4 |
Gastrointestinal | |
Constipation | 14 |
Nausea | 5 |
Abdominal Discomfort/Heartburn | 4 |
Nausea/Vomiting | 3 |
Vomiting | 3 |
Diarrhea | 2 |
Urogenital | |
Urinary Abnormalities | 2 |
Autonomic Nervous System | |
Salivation | 31 |
Sweating | 6 |
Dry Mouth | 6 |
Visual Disturbances | 5 |
Skin | |
Rash | 2 |
Hemic/Lymphatic | |
Leukopenia/Decreased WBC/Neutropenia | 3 |
Miscellaneous | |
Fever | 5 |
Weight Gain | 4 |
† Rate based on population of approximately 1700 exposed during premarket clinical evaluation of clozapine. |
Table 11 summarizes the most commonly reported adverse reactions ( > 10% of the clozapine or olanzapine group) in the InterSePT™ Study. This was an adequate and well-controlled, two-year study evaluating the efficacy of clozapine relative to olanzapine in reducing the risk of suicidal behavior in patients with schizophrenia or schizoaffective disorder. The rates are not adjusted for duration of exposure.
Table 11: Incidence of Adverse Reactions in Patients
Treated with Clozapine or Olanzapine in the InterSePT™ Study ( ≥ 10% in the
clozapine or olanzapine group)
Adverse Reactions | Clozapine N=479 % Reporting |
Olanzapine N=477 % Reporting |
Salivary hypersecretion | 48% | 6% |
Somnolence | 46% | 25% |
Weight increased | 31% | 56% |
Dizziness (excluding vertigo) | 27% | 12% |
Constipation | 25% | 10% |
Insomnia. | 20% | 33% |
Nausea | 17% | 10% |
Vomiting | 17% | 9% |
Dyspepsia | 14% | 8% |
Class effect: Symptoms of dystonia, prolonged abnormal contractions of muscle groups, may occur in susceptible individuals during the first few days of treatment. Dystonic symptoms include: spasm of the neck muscles, sometimes progressing to tightness of the throat, swallowing difficulty, difficulty breathing, and/or protrusion of the tongue. While these symptoms can occur at low doses, they occur more frequently and with greater severity with high potency and at higher doses of first generation antipsychotic drugs. An elevated risk of acute dystonia is observed in males and younger age groups.
Postmarketing ExperienceThe 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 SystemDelirium, EEG abnormal, myoclonus, paresthesia, possible cataplexy, status epilepticus, obsessive compulsive symptoms, and post-discontinuation cholinergic rebound adverse reactions.
Cardiovascular SystemAtrial or ventricular fibrillation, ventricular tachycardia, QT interval prolongation, Torsades de Pointes, myocardial infarction, cardiac arrest, and periorbital edema.
Endocrine SystemPseudopheochromocytoma.
Gastrointestinal SystemAcute pancreatitis, dysphagia, salivary gland swelling.
Hepatobiliary SystemCholestasis, hepatitis, jaundice, hepatotoxicity, hepatic steatosis, hepatic necrosis, hepatic fibrosis, hepatic cirrhosis, liver injury (hepatic, cholestatic, and mixed), and liver failure.
Immune System DisordersAngioedema, leukocytoclastic vasculitis.
Urogenital SystemAcute interstitial nephritis, nocturnal enuresis, priapism, and renal failure.
Skin and Subcutaneous Tissue DisordersHypersensitivity reactions: photosensitivity, vasculitis, erythema multiforme, skin pigmentation disorder, and Stevens-Johnson Syndrome.
Musculoskeletal System and Connective Tissue DisordersMyasthenic syndrome, rhabdomyolysis, and systemic lupus erythematosus.
Respiratory SystemAspiration, pleural effusion, pneumonia, lower respiratory tract infection.
Hemic and Lymphatic SystemMild, moderate, or severe leukopenia, agranulocytosis, granulocytopenia, WBC decreased, deep vein thrombosis, elevated hemoglobin/hematocrit, erythrocyte sedimentation rate (ESR) increased, sepsis, thrombocytosis, and thrombocytopenia.
Vision DisordersNarrow-angle glaucoma.
MiscellaneousCreatine phosphokinase elevation, hyperuricemia, hyponatremia, and weight loss.
DRUG INTERACTIONS Potential For Other Drugs To Affect VERSACLOZClozapine is a substrate for many cytochrome P450 isozymes, in particular CYP1A2, CYP3A4, and CYP2D6. Use caution when administering VERSACLOZ concomitantly with drugs that are inducers or inhibitors of these enzymes.
CYP1A2 InhibitorsConcomitant use of VERSACLOZ and CYP1A2 inhibitors can increase plasma levels of clozapine, potentially resulting in adverse reactions. Reduce the VERSACLOZ dose to one third of the original dose when VERSACLOZ is coadministered with strong CYP1A2 inhibitors (e.g., fluvoxamine, ciprofloxacin, or enoxacin). The VERSACLOZ dose should be increased to the original dose when coadministration of strong CYP1A2 inhibitors is discontinued .
Moderate or weak CYP1A2 inhibitors include oral contraceptives and caffeine. Monitor patients closely when VERSACLOZ is coadministered with these inhibitors. Consider reducing the VERSACLOZ dosage if necessary.
CYP2D6 And CYP3A4 InhibitorsConcomitant treatment with VERSACLOZ 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. Use caution and monitor patients closely when using such inhibitors. Consider reducing the VERSACLOZ dose.
CYP1A2 And CYP3A4 InducersConcomitant treatment with drugs that induce CYP1A2 or CYP3A4 can decrease the plasma concentration of clozapine, resulting in decreased effectiveness of VERSACLOZ. 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 VERSACLOZ dose if used concomitantly with inducers of these enzymes. However, concomitant use of VERSACLOZ and strong CYP3A4 inducers is not recommended.
Consider reducing the VERSACLOZ dosage when discontinuing coadministered enzyme inducers, because discontinuation of inducers can result in increased clozapine plasma levels and an increased risk of adverse reactions .
Drugs That Cause QT Interval ProlongationUse caution when administering concomitant medications that prolong the QT interval or inhibit the metabolism of VERSACLOZ. Drugs that cause QT prolongation include: specific antipsychotics (e.g., ziprasidone, iloperidone, chlorpromazine, thioridazine, mesoridazine, droperidol, and pimozide), specific antibiotics (e.g., erythromycin, gatifloxacin, moxifloxacin, sparfloxacin), Class 1A antiarrhythmics (e.g., quinidine, procainamide) or Class III antiarrhythmics (e.g., amiodarone, sotalol), and others (e.g., pentamidine, levomethadyl acetate, methadone, halofantrine, mefloquine, dolasetron mesylate, probucol or tacrolimus).
Potential For VERSACLOZ To Affect Other DrugsConcomitant use of VERSACLOZ with other drugs metabolized by CYP2D6 can increase levels of these CYP2D6 substrates. Use caution when coadministering VERSACLOZ with other drugs that are metabolized by CYP2D6. It may be necessary to use lower doses of such drugs than usually prescribed. Such drugs include specific antidepressants, phenothiazines, carbamazepine, and Type 1C antiarrhythmics (e.g., propafenone, flecainide, and encainide).