Sabril
vigabatrin · Powder, For Solution · Oral
Uses
1 INDICATIONS AND USAGE SABRIL is indicated for the treatment of: Refractory Complex Partial Seizures as adjunctive therapy in patients 2 years of age and older who have responded inadequately to several alternative treatments; SABRIL is not indicated as a first line agent ( 1.1 ) Infantile Spasms - monotherapy in infants 1 month to 2 years of age for whom the potential benefits outweigh the potential risk of vision loss ( 1.2 ) 1.1 Refractory Complex Partial Seizures (CPS) SABRIL is indicated as adjunctive therapy for adults and pediatric patients 2 years of age and older with refractory complex partial seizures who have inadequately responded to several alternative treatments and for whom the potential benefits outweigh the risk of vision loss [see Warnings and Precautions ( 5.1 )] . SABRIL is not indicated as a first line agent for complex partial seizures. 1.2 Infantile Spasms (IS) SABRIL is indicated as monotherapy for pediatric patients with infantile spasms 1 month to 2 years of age for whom the potential benefits outweigh the potential risk of vision loss [see Warnings and Precautions ( 5.1 ) ].
Dosage and administration
Refractory Complex Partial Seizures Adults (17 years of age and older): Initiate at 1000 mg/day (500 mg twice daily); increase total daily dose weekly in 500 mg/day increments, to the recommended dose of 3000 mg/day (1500 mg twice daily) ( 2.2 ) Pediatric (2 to 16 years of age): The recommended dosage is based on body weight and administered as two divided doses ( 2.2 ) The dosage may be increased in weekly intervals, depending on response ( 2.2 ) Dose patients weighing more than 60 kg according to adult recommendations ( 2.2 ) Infantile Spasms Initiate at a daily dose of 50 mg/kg (25 mg/kg twice daily); increase total daily dose every 3 days, in increments of 25 mg/kg/day to 50 mg/kg/day, up to a maximum daily dose of 150 mg/kg (75 mg/kg twice daily) ( 2.3 ) Renal Impairment : Dose adjustment recommended ( 2.4 , 8.5 , 8.6 ) 2.1 Important Dosing and Administration Instructions Dosing Use the lowest dosage and shortest exposure to SABRIL consistent with clinical objectives [see Warnings and Precautions ( 5.1 )]. The SABRIL dosing regimen depends on the indication, age group, weight, and dosage form (tablets or for oral solution) [see Dosage and Administration ( 2.2 , 2.3 )]. Patients with impaired renal function require dose adjustment [see Dosage and Administration ( 2.4 )]. Monitoring of SABRIL plasma concentrations to optimize therapy is not helpful. Administration SABRIL is given orally with or without food. SABRIL for oral solution should be mixed with water prior to administration [see Dosage and Administration ( 2.5 )]. A calibrated measuring device is recommended to measure and deliver the prescribed dose accurately. A household teaspoon or tablespoon is not an adequate measuring device. If a decision is made to discontinue SABRIL, the dose should be gradually reduced [see Dosage and Administration ( 2.2 , 2.3 ) and Warnings and Precautions ( 5.6 ) ]. 2.2 Refractory Complex Partial Seizures Adults (Patients 17 Years of Age and Older) Treatment should be initiated at 1000 mg/day (500 mg twice daily). Total daily dose may be increased in 500 mg increments at weekly intervals depending on response. The recommended dose of SABRIL in adults is 3000 mg/day (1500 mg twice daily). A 6000 mg/day dose has not been shown to confer additional benefit compared to the 3000 mg/day dose and is associated with an increased incidence of adverse events. In controlled clinical studies in adults with complex partial seizures, SABRIL was tapered by decreasing the daily dose 1000 mg/day on a weekly basis until discontinued [see Warnings and Precautions ( 5.6 )]. Pediatric (Patients 2 to 16 Years of Age) The recommended dosage is based on body weight and administered as two divided doses, as shown in Table 1. The dosage may be increased in weekly intervals to the total daily maintenance dosage, depending on response. Pediatric patients weighing more than 60 kg should be dosed according to adult recommendations. Table 1. CPS Dosing Recommendations for Pediatric Patients Weighing 10 kg up to 60 kg †† Body Weight [kg] Total Daily* Starting Dose [mg/day] Total Daily* Maintenance Dose † [mg/day] 10 kg to 15 kg 350 mg 1050 mg Greater than 15 kg to 20 kg 450 mg 1300 mg Greater than 20 kg to 25 kg 500 mg 1500 mg Greater than 25 kg to 60 kg 500 mg 2000 mg * Administered in two divided doses † Maintenance dose is based on 3000 mg/day adult-equivalent dose †† Patients weighing more than 60 kg should be dosed according to adult recommendations In patients with refractory complex partial seizures, SABRIL should be withdrawn if a substantial clinical benefit is not observed within 3 months of initiating treatment. If, in the clinical judgment of the prescriber, evidence of treatment failure becomes obvious earlier than 3 months, treatment should be discontinued at that time [see Warnings and Precautions ( 5.1 )]. In a controlled study in pediatric patients with complex partial seizures, SABRIL was tapered by decreasing the daily dose by one third every week for three weeks [see Warnings and Precautions ( 5.6 )]. 2.3 Infantile Spasms The initial daily dosing is 50 mg/kg/day given in two divided doses (25 mg/kg twice daily); subsequent dosing can be titrated by 25 mg/kg/day to 50 mg/kg/day increments every 3 days, up to a maximum of 150 mg/kg/day given in 2 divided doses (75 mg/kg twice daily) [ s ee Use in Specific Populations ( 8.4 ) ] . Table 2 provides the volume of the 50 mg/mL dosing solution that should be administered as individual doses in infants of various weights. Table 2. Infant Dosing Table Weight [kg] Starting Dose 50 mg/kg/day Maximum Dose 150 mg/kg/day 3 1.5 mL twice daily 4.5 mL twice daily 4 2 mL twice daily 6 mL twice daily 5 2.5 mL twice daily 7.5 mL twice daily 6 3 mL twice daily 9 mL twice daily 7 3.5 mL twice daily 10.5 mL twice daily 8 4 mL twice daily 12 mL twice daily 9 4.5 mL twice daily 13.5 mL twice daily 10 5 mL twice daily 15 mL twice daily 11 5.5 mL twice daily 16.5 mL twice daily 12 6 mL twice daily 18 mL twice daily 13 6.5 mL twice daily 19.5 mL twice daily 14 7 mL twice daily 21 mL twice daily 15 7.5 mL twice daily 22.5 mL twice daily 16 8 mL twice daily 24 mL twice daily In patients with infantile spasms, SABRIL should be withdrawn if a substantial clinical benefit is not observed within 2 to 4 weeks. If, in the clinical judgment of the prescriber, evidence of treatment failure becomes obvious earlier than 2 to 4 weeks, treatment should be discontinued at that time [see Warnings and Precautions ( 5.1 )]. In a controlled clinical study in patients with infantile spasms, SABRIL was tapered by decreasing the daily dose at a rate of 25 mg/kg to 50 mg/kg every 3 to 4 days [see Warnings and Precautions ( 5.6 )]. 2.4 Patients with Renal Impairment SABRIL is primarily eliminated through the kidney. Infants Information about how to adjust the dose in infants with renal impairment is unavailable.
Dosage forms and strengths
Tablet: 500 mg: white, oval, film-coated, biconvex, scored on one side, and debossed with OV 111 on the other. For oral solution: 500 mg packet containing a white to off-white granular powder. Tablet: 500 mg ( 3 ) For oral solution: 500 mg per packet ( 3 )
Contraindications
None. None ( 4 )
Warnings and precautions
Abnormal MRI signal changes and intramyelinic edema have been reported in some infants with Infantile Spasms receiving SABRIL ( 5.3 , 5.4 ) Suicidal behavior and ideation: Antiepileptic drugs, including SABRIL, increase the risk of suicidal thoughts and behavior ( 5.5 ) Withdrawal of AEDs: Taper dose to avoid withdrawal seizures ( 5.6 ) Anemia: Monitor for symptoms of anemia ( 5.7 ) Somnolence and fatigue: Advise patients not to drive or operate machinery until they have gained sufficient experience on SABRIL ( 5.8 ) 5.1 Permanent Vision Loss SABRIL can cause permanent vision loss. Because of this risk and because, when it is effective, SABRIL provides an observable symptomatic benefit; patient response and continued need for treatment should be periodically assessed. Based upon adult studies, 30 percent or more of patients can be affected with bilateral concentric visual field constriction ranging in severity from mild to severe. Severe cases may be characterized by tunnel vision to within 10 degrees of visual fixation, which can result in disability. In some cases, SABRIL also can damage the central retina and may decrease visual acuity. Symptoms of vision loss from SABRIL are unlikely to be recognized by patients or caregivers before vision loss is severe. Vision loss of milder severity, while often unrecognized by the patient or caregiver, can still adversely affect function. Because assessing vision may be difficult in infants and children, the frequency and extent of vision loss is poorly characterized in these patients. For this reason, the understanding of the risk is primarily based on the adult experience. The possibility that vision loss from SABRIL may be more common, more severe, or have more severe functional consequences in infants and children than in adults cannot be excluded. The onset of vision loss from SABRIL is unpredictable and can occur within weeks of starting treatment or sooner, or at any time after starting treatment, even after months or years. The risk of vision loss increases with increasing dose and cumulative exposure, but there is no dose or exposure known to be free of risk of vision loss. In patients with refractory complex partial seizures, SABRIL should be withdrawn if a substantial clinical benefit is not observed within 3 months of initiating treatment. If, in the clinical judgment of the prescriber, evidence of treatment failure becomes obvious earlier than 3 months, treatment should be discontinued at that time [see Dosage and Administration ( 2.2 ) and Warnings and Precautions ( 5.6 )] . In patients with infantile spasms, SABRIL should be withdrawn if a substantial clinical benefit is not observed within 2 to 4 weeks. If, in the clinical judgment of the prescriber, evidence of treatment failure becomes obvious earlier than 2 to 4 weeks, treatment should be discontinued at that time [see Dosage and Administration ( 2.3 ) and Warnings and Precautions ( 5.6 )]. SABRIL should not be used in patients with, or at high risk of, other types of irreversible vision loss unless the benefits of treatment clearly outweigh the risks. The interaction of other types of irreversible vision damage with vision damage from SABRIL has not been well-characterized, but is likely adverse. SABRIL should not be used with other drugs associated with serious adverse ophthalmic effects such as retinopathy or glaucoma unless the benefits clearly outweigh the risks. Monitoring of Vision Monitoring of vision by an ophthalmic professional with expertise in visual field interpretation and the ability to perform dilated indirect ophthalmoscopy of the retina is recommended [see Warnings and Precautions ( 5.2 )]. Because vision testing in infants is difficult, vision loss may not be detected until it is severe. For patients receiving SABRIL, vision assessment is recommended at baseline (no later than 4 weeks after starting SABRIL), at least every 3 months while on therapy, and about 3-6 months after the discontinuation of therapy. The diagnostic approach should be individualized for the patient and clinical situation. In adults and cooperative pediatric patients, perimetry is recommended, preferably by automated threshold visual field testing. Additional testing may also include electrophysiology (e.g., electroretinography [ERG]), retinal imaging (e.g., optical coherence tomography [OCT]), and/or other methods appropriate for the patient. In patients who cannot be tested, treatment may continue according to clinical judgment, with appropriate patient counseling. Because of variability, results from ophthalmic monitoring must be interpreted with caution, and repeat assessment is recommended if results are abnormal or uninterpretable. Repeat assessment in the first few weeks of treatment is recommended to establish if, and to what degree, reproducible results can be obtained, and to guide selection of appropriate ongoing monitoring for the patient. The onset and progression of vision loss from SABRIL is unpredictable, and it may occur or worsen precipitously between assessments. Once detected, vision loss due to SABRIL is not reversible. It is expected that even with frequent monitoring, some SABRIL patients will develop severe vision loss. Consider drug discontinuation, balancing benefit and risk, if vision loss is documented. It is possible that vision loss can worsen despite discontinuation of SABRIL. 5.2 Vigabatrin REMS Program SABRIL is available only through a restricted distribution program called the Vigabatrin REMS Program, because of the risk of permanent vision loss. Notable requirements of the Vigabatrin REMS Program include the following: Prescribers must be certified by enrolling in the program, agreeing to counsel patients on the risk of vision loss and the need for periodic monitoring of vision, and reporting any event suggestive of vision loss to Lundbeck. Patients must enroll in the program.
Side effects
The following serious and otherwise important adverse reactions are described elsewhere in labeling: Permanent Vision Loss [see BOXED WARNING and Warnings and Precautions ( 5.1 ) ] Magnetic Resonance Imaging (MRI) Abnormalities in Infants [see Warnings and Precautions ( 5.3 ) ] Neurotoxicity [see Warnings and Precautions ( 5.4 )] Suicidal Behavior and Ideation [see Warnings and Precautions ( 5.5 ) ] Withdrawal of Antiepileptic Drugs (AEDs) [see Warnings and Precautions ( 5.6 ) ] Anemia [see Warnings and Precautions ( 5.7 ) ] Somnolence and Fatigue [see Warnings and Precautions ( 5.8 ) ] Peripheral Neuropathy [see Warnings and Precautions ( 5.9 )] Weight Gain [see Warnings and Precautions ( 5.10 ) ] Edema [see Warnings and Precautions ( 5.11 )] Refractory Complex Partial Seizures Most common adverse reactions in controlled studies include (incidence ≥5% over placebo): Adults: blurred vision, somnolence, dizziness, abnormal coordination, tremor, and fatigue ( 6.1 ) Pediatric patients (3 to 16 years of age): weight gain ( 6.1 ) Infantile Spasms (incidence >5% and greater than on placebo) Somnolence, bronchitis, ear infection, and acute otitis media ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Lundbeck at 1-800-455-1141 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trial Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. In U.S. and primary non-U.S. clinical studies of 4,079 SABRIL-treated patients, the most common (≥5%) adverse reactions associated with the use of SABRIL in combination with other AEDs were headache, somnolence, fatigue, dizziness, convulsion, nasopharyngitis, weight gain, upper respiratory tract infection, visual field defect, depression, tremor, nystagmus, nausea, diarrhea, memory impairment, insomnia, irritability, abnormal coordination, blurred vision, diplopia, vomiting, influenza, pyrexia, and rash. The adverse reactions most commonly associated with SABRIL treatment discontinuation in ≥1% of patients were convulsion and depression. In patients with infantile spasms, the adverse reactions most commonly associated with SABRIL treatment discontinuation in ≥1% of patients were infections, status epilepticus, developmental coordination disorder, dystonia, hypotonia, hypertonia, weight gain, and insomnia. Refractory C omplex Partial Seizures Adults Table 5 lists the adverse reactions that occurred in ≥2% and more than one patient per SABRIL-treated group and that occurred more frequently than in placebo patients from 2 U.S. adjunctive clinical studies of refractory CPS in adults. Table 5. Adverse Reactions in Pooled, Adjunctive Trials in Adults with Refractory Complex Partial Seizures SABRIL dosage (mg/day) Body System Adverse Reaction 3000 [N=134] % 6000 [N=43] % Placebo [N=135] % Ear Disorders Tinnitus 2 0 1 Vertigo 2 5 1 Eye Disorders Blurred vision 13 16 5 Diplopia 7 16 3 Asthenopia 2 2 0 Eye pain 0 5 0 Gastrointestinal Disorders Diarrhea 10 16 7 Nausea 10 2 8 Vomiting 7 9 6 Constipation 8 5 3 Upper abdominal pain 5 5 1 Dyspepsia 4 5 3 Stomach discomfort 4 2 1 Abdominal pain 3 2 1 Toothache 2 5 2 Abdominal distension 2 0 1 General Disorders Fatigue 23 40 16 Gait disturbance 6 12 7 Asthenia 5 7 1 Edema peripheral 5 7 1 Fever 4 7 3 Chest pain 1 5 1 Thirst 2 0 0 Malaise 0 5 0 Infections Nasopharyngitis 14 9 10 Upper respiratory tract infection 7 9 6 Influenza 5 7 4 Urinary tract infection 4 5 0 Bronchitis 0 5 1 Injury Contusion 3 5 2 Joint sprain 1 2 1 Muscle strain 1 2 1 Wound secretion 0 2 0 Metabolism and Nutrition Disorders Increased appetite 1 5 1 Weight gain 6 14 3 Musculoskeletal Disorders Arthralgia 10 5 3 Back pain 4 7 2 Pain in extremity 6 2 4 Myalgia 3 5 1 Muscle twitching 1 9 1 Muscle spasms 3 0 1 Nervous System Disorders Headache 33 26 31 Somnolence 22 26 13 Dizziness 24 26 17 Nystagmus 13 19 9 Tremor 15 16 8 Memory impairment 7 16 3 Abnormal coordination 7 16 2 Disturbance in attention 9 0 1 Sensory disturbance 4 7 2 Hyporeflexia 4 5 1 Paraesthesia 7 2 1 Lethargy 4 7 2 Hyperreflexia 4 2 3 Hypoaesthesia 4 5 1 Sedation 4 0 0 Status epilepticus 2 5 0 Dysarthria 2 2 1 Postictal state 2 0 1 Sensory loss 0 5 0 Psychiatric Disorders Irritability 7 23 7 Depression 6 14 3 Confusional state 4 14 1 Anxiety 4 0 3 Depressed mood 5 0 1 Abnormal thinking 3 7 0 Abnormal behavior 3 5 1 Expressive language disorder 1 7 1 Nervousness 2 5 2 Abnormal dreams 1 5 1 Reproductive System Dysmenorrhea 9 5 3 Erectile dysfunction 0 5 0 Respiratory and Thoracic Disorders Pharyngolaryngeal pain 7 14 5 Cough 2 14 7 Pulmonary congestion 0 5 1 Sinus headache 6 2 1 Skin and Subcutaneous Tissue Disorders Rash 4 5 4 Pediatrics 2 to 16 years of age Table 6 lists adverse reactions from controlled clinical studies of pediatric patients receiving SABRIL or placebo as adjunctive therapy for refractory complex partial seizures. Adverse reactions that are listed occurred in at least 2% of SABRIL-treated patients and more frequently than placebo. The median SABRIL dose was 49.4 mg/kg (range of 8.0 – 105.9 mg/kg). Table 6.
Drug interactions
Decreased phenytoin plasma levels: dosage adjustment may be needed ( 7.1 ) 7.1 Antiepileptic Drugs Phenytoin Although phenytoin dose adjustments are not routinely required, dose adjustment of phenytoin should be considered if clinically indicated, since SABRIL may cause a moderate reduction in total phenytoin plasma levels [see Clinical Pharmacology ( 12.3 )]. Clonazepam SABRIL may moderately increase the C max of clonazepam resulting in an increase of clonazepam-associated adverse reactions [see Clinical Pharmacology ( 12.3 )]. Other AEDs There are no clinically significant pharmacokinetic interactions between SABRIL and either phenobarbital or sodium valproate. Based on population pharmacokinetics, carbamazepine, clorazepate, primidone, and sodium valproate appear to have no effect on plasma concentrations of vigabatrin [see Clinical Pharmacology ( 12.3 )]. 7.2 Oral Contraceptives SABRIL is unlikely to affect the efficacy of steroid oral contraceptives [see Clinical Pharmacology ( 12.3 ) ] . 7.3 Drug-Laboratory Test Interactions SABRIL decreases alanine transaminase (ALT) and aspartate transaminase (AST) plasma activity in up to 90% of patients. In some patients, these enzymes become undetectable. The suppression of ALT and AST activity by SABRIL may preclude the use of these markers, especially ALT, to detect early hepatic injury. SABRIL may increase the amount of amino acids in the urine, possibly leading to a false positive test for certain rare genetic metabolic diseases (e.g., alpha aminoadipic aciduria).
Use in specific populations
Pregnancy: Based on animal data, may cause fetal harm. ( 8.1 ) Lactation: SABRIL is excreted in human milk ( 8.2 ) 8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to AEDs, including SABRIL, during pregnancy. Encourage women who are taking SABRIL during pregnancy to enroll in the North American Antiepileptic Drug (NAAED) Pregnancy Registry. This can be done by calling the toll-free number 1-888-233-2334 or visiting the website, http://www.aedpregnancyregistry.org/ . This must be done by the patient herself. Risk Summary There are no adequate data on the developmental risk associated with the use of SABRIL in pregnant women. Limited available data from case reports and cohort studies pertaining to SABRIL use in pregnant women have not established a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes. However, based on animal data, SABRIL use in pregnant women may result in fetal harm. When administered to pregnant animals, vigabatrin produced developmental toxicity, including an increase in fetal malformations and offspring neurobehavioral and neurohistopathological effects, at clinically relevant doses. In addition, developmental neurotoxicity was observed in rats treated with vigabatrin during a period of postnatal development corresponding to the third trimester of human pregnancy (see Data) . In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively. The background risk of major birth defects and miscarriage for the indicated population is unknown. Data Animal Data Administration of vigabatrin (oral doses of 50 to 200 mg/kg/day) to pregnant rabbits throughout the period of organogenesis was associated with an increased incidence of malformations (cleft palate) and embryofetal death; these findings were observed in two separate studies. The no-effect dose for adverse effects on embryofetal development in rabbits (100 mg/kg/day) is approximately 1/2 the maximum recommended human dose (MRHD) of 3 g/day on a body surface area (mg/m 2 ) basis. In rats, oral administration of vigabatrin (50, 100, or 150 mg/kg/day) throughout organogenesis resulted in decreased fetal body weights and increased incidences of fetal anatomic variations. The no-effect dose for adverse effects on embryo-fetal development in rats (50 mg/kg/day) is approximately 1/5 the MRHD on a mg/m 2 basis. Oral administration of vigabatrin (50, 100, 150 mg/kg/day) to rats from the latter part of pregnancy through weaning produced long-term neurohistopathological (hippocampal vacuolation) and neurobehavioral (convulsions) abnormalities in the offspring. A no-effect dose for developmental neurotoxicity in rats was not established; the low-effect dose (50 mg/kg/day) is approximately 1/5 the MRHD on a mg/m 2 basis. In a published study, vigabatrin (300 or 450 mg/kg) was administered by intraperitoneal injection to a mutant mouse strain on a single day during organogenesis (day 7, 8, 9, 10, 11, or 12). An increase in fetal malformations (including cleft palate) was observed at both doses. Oral administration of vigabatrin (5, 15, or 50 mg/kg/day) to young rats during the neonatal and juvenile periods of development (postnatal days 4-65) produced neurobehavioral (convulsions, neuromotor impairment, learning deficits) and neurohistopathological (brain vacuolation, decreased myelination, and retinal dysplasia) abnormalities in treated animals. The early postnatal period in rats is generally thought to correspond to late pregnancy in humans in terms of brain development. The no-effect dose for developmental neurotoxicity in juvenile rats (5 mg/kg/day) was associated with plasma vigabatrin exposures (AUC) less than 1/30 of those measured in pediatric patients receiving an oral dose of 50 mg/kg. 8.2 Lactation Risk Summary Vigabatrin is excreted in human milk. The effects of SABRIL on the breastfed infant and on milk production are unknown. Because of the potential for serious adverse reactions from vigabatrin in nursing infants, breastfeeding is not recommended. If exposing a breastfed infant to SABRIL, observe for any potential adverse effects [see Warnings and Precautions ( 5.1 , 5.3 , 5.4 , 5.8 )] . 8.4 Pediatric Use The safety and effectiveness of SABRIL as adjunctive treatment of refractory complex partial seizures in pediatric patients 2 to 16 years of age have been established and is supported by three double-blind, placebo-controlled studies in patients 3 to 16 years of age, adequate and well-controlled studies in adult patients, pharmacokinetic data from patients 2 years of age and older, and additional safety information in patients 2 years of age [see Clinical Pharmacology ( 12.3 ) and Clinical Studies ( 14.1 )]. The dosing recommendation in this population varies according to age group and is weight-based [see Dosage and Administration ( 2.2 )]. Adverse reactions in this pediatric population are similar to those observed in the adult population [see Adverse Reactions ( 6.1 )] . The safety and effectiveness of SABRIL as monotherapy for pediatric patients with infantile spasms (1 month to 2 years of age) have been established [see Dosage and Administration ( 2.3 ) and Clinical Studies ( 14.2 )] . Safety and effectiveness as adjunctive treatment of refractory complex partial seizures in pediatric patients below the age of 2 and as monotherapy for the treatment of infantile spasms in pediatric patients below the age of 1 month have not been established. Duration of therapy for infantile spasms was evaluated in a post hoc analysis of a Canadian Pediatric Epilepsy Network (CPEN) study of developmental outcomes in infantile spasms patients. This analysis suggests that a total duration of 6 months of vigabatrin therapy is adequate for the treatment of infantile spasms.
Pregnancy
8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to AEDs, including SABRIL, during pregnancy. Encourage women who are taking SABRIL during pregnancy to enroll in the North American Antiepileptic Drug (NAAED) Pregnancy Registry. This can be done by calling the toll-free number 1-888-233-2334 or visiting the website, http://www.aedpregnancyregistry.org/ . This must be done by the patient herself. Risk Summary There are no adequate data on the developmental risk associated with the use of SABRIL in pregnant women. Limited available data from case reports and cohort studies pertaining to SABRIL use in pregnant women have not established a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes. However, based on animal data, SABRIL use in pregnant women may result in fetal harm. When administered to pregnant animals, vigabatrin produced developmental toxicity, including an increase in fetal malformations and offspring neurobehavioral and neurohistopathological effects, at clinically relevant doses. In addition, developmental neurotoxicity was observed in rats treated with vigabatrin during a period of postnatal development corresponding to the third trimester of human pregnancy (see Data) . In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively. The background risk of major birth defects and miscarriage for the indicated population is unknown. Data Animal Data Administration of vigabatrin (oral doses of 50 to 200 mg/kg/day) to pregnant rabbits throughout the period of organogenesis was associated with an increased incidence of malformations (cleft palate) and embryofetal death; these findings were observed in two separate studies. The no-effect dose for adverse effects on embryofetal development in rabbits (100 mg/kg/day) is approximately 1/2 the maximum recommended human dose (MRHD) of 3 g/day on a body surface area (mg/m 2 ) basis. In rats, oral administration of vigabatrin (50, 100, or 150 mg/kg/day) throughout organogenesis resulted in decreased fetal body weights and increased incidences of fetal anatomic variations. The no-effect dose for adverse effects on embryo-fetal development in rats (50 mg/kg/day) is approximately 1/5 the MRHD on a mg/m 2 basis. Oral administration of vigabatrin (50, 100, 150 mg/kg/day) to rats from the latter part of pregnancy through weaning produced long-term neurohistopathological (hippocampal vacuolation) and neurobehavioral (convulsions) abnormalities in the offspring. A no-effect dose for developmental neurotoxicity in rats was not established; the low-effect dose (50 mg/kg/day) is approximately 1/5 the MRHD on a mg/m 2 basis. In a published study, vigabatrin (300 or 450 mg/kg) was administered by intraperitoneal injection to a mutant mouse strain on a single day during organogenesis (day 7, 8, 9, 10, 11, or 12). An increase in fetal malformations (including cleft palate) was observed at both doses. Oral administration of vigabatrin (5, 15, or 50 mg/kg/day) to young rats during the neonatal and juvenile periods of development (postnatal days 4-65) produced neurobehavioral (convulsions, neuromotor impairment, learning deficits) and neurohistopathological (brain vacuolation, decreased myelination, and retinal dysplasia) abnormalities in treated animals. The early postnatal period in rats is generally thought to correspond to late pregnancy in humans in terms of brain development. The no-effect dose for developmental neurotoxicity in juvenile rats (5 mg/kg/day) was associated with plasma vigabatrin exposures (AUC) less than 1/30 of those measured in pediatric patients receiving an oral dose of 50 mg/kg.
Pediatric use
8.4 Pediatric Use The safety and effectiveness of SABRIL as adjunctive treatment of refractory complex partial seizures in pediatric patients 2 to 16 years of age have been established and is supported by three double-blind, placebo-controlled studies in patients 3 to 16 years of age, adequate and well-controlled studies in adult patients, pharmacokinetic data from patients 2 years of age and older, and additional safety information in patients 2 years of age [see Clinical Pharmacology ( 12.3 ) and Clinical Studies ( 14.1 )]. The dosing recommendation in this population varies according to age group and is weight-based [see Dosage and Administration ( 2.2 )]. Adverse reactions in this pediatric population are similar to those observed in the adult population [see Adverse Reactions ( 6.1 )] . The safety and effectiveness of SABRIL as monotherapy for pediatric patients with infantile spasms (1 month to 2 years of age) have been established [see Dosage and Administration ( 2.3 ) and Clinical Studies ( 14.2 )] . Safety and effectiveness as adjunctive treatment of refractory complex partial seizures in pediatric patients below the age of 2 and as monotherapy for the treatment of infantile spasms in pediatric patients below the age of 1 month have not been established. Duration of therapy for infantile spasms was evaluated in a post hoc analysis of a Canadian Pediatric Epilepsy Network (CPEN) study of developmental outcomes in infantile spasms patients. This analysis suggests that a total duration of 6 months of vigabatrin therapy is adequate for the treatment of infantile spasms. However, prescribers must use their clinical judgment as to the most appropriate duration of use [see Clinical Studies ( 14.2 )]. Abnormal MRI signal changes and Intramyelinic Edema (IME) in infants and young children being treated with SABRIL have been observed [see Warnings and Precautions ( 5.3 , 5.4 )] . Juvenile Animal Toxicity Data Oral administration of vigabatrin (5, 15, or 50 mg/kg/day) to young rats during the neonatal and juvenile periods of development (postnatal days 4-65) produced neurobehavioral (convulsions, neuromotor impairment, learning deficits) and neurohistopathological (brain gray matter vacuolation, decreased myelination, and retinal dysplasia) abnormalities. The no-effect dose for developmental neurotoxicity in juvenile rats (the lowest dose tested) was associated with plasma vigabatrin exposures (AUC) substantially less than those measured in pediatric patients at recommended doses. In dogs, oral administration of vigabatrin (30 or 100 mg/kg/day) during selected periods of juvenile development (postnatal days 22-112) produced neurohistopathological abnormalities (brain gray matter vacuolation). Neurobehavioral effects of vigabatrin were not assessed in the juvenile dog. A no-effect dose for neurohistopathology was not established in juvenile dogs; the lowest effect dose (30 mg/kg/day) was associated with plasma vigabatrin exposures lower than those measured in pediatric patients at recommended doses [see Warnings and Precautions ( 5.4 )].
Geriatric use
8.5 Geriatric Use Clinical studies of vigabatrin did not include sufficient numbers of patients aged 65 and over to determine whether they responded differently from younger patients. Vigabatrin is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function. Oral administration of a single dose of 1.5 g of vigabatrin to elderly (≥65 years) patients with reduced creatinine clearance (<50 mL/min) was associated with moderate to severe sedation and confusion in 4 of 5 patients, lasting up to 5 days. The renal clearance of vigabatrin was 36% lower in healthy elderly subjects (≥65 years) than in young healthy males. Adjustment of dose or frequency of administration should be considered. Such patients may respond to a lower maintenance dose [see Dosage and Administration ( 2.4 ) and Clinical Pharmacology ( 12.3 )] . Other reported clinical experience has not identified differences in responses between the elderly and younger patients.
Overdosage
10.1 Signs, Symptoms, and Laboratory Findings of Overdosage Confirmed and/or suspected vigabatrin overdoses have been reported during clinical trials and in post marketing surveillance. No vigabatrin overdoses resulted in death. When reported, the vigabatrin dose ingested ranged from 3 g to 90 g, but most were between 7.5 g and 30 g. Nearly half the cases involved multiple drug ingestions including carbamazepine, barbiturates, benzodiazepines, lamotrigine, valproic acid, acetaminophen, and/or chlorpheniramine. Coma, unconsciousness, and/or drowsiness were described in the majority of cases of vigabatrin overdose. Other less commonly reported symptoms included vertigo, psychosis, apnea or respiratory depression, bradycardia, agitation, irritability, confusion, headache, hypotension, abnormal behavior, increased seizure activity, status epilepticus, and speech disorder. These symptoms resolved with supportive care. 10.2 Management of Overdosage There is no specific antidote for SABRIL overdose. Standard measures to remove unabsorbed drug should be used, including elimination by emesis or gastric lavage. Supportive measures should be employed, including monitoring of vital signs and observation of the clinical status of the patient. In an in vitro study, activated charcoal did not significantly adsorb vigabatrin. The effectiveness of hemodialysis in the treatment of SABRIL overdose is unknown. In isolated case reports in renal failure patients receiving therapeutic doses of vigabatrin, hemodialysis reduced vigabatrin plasma concentrations by 40% to 60%.
Description
(vigabatrin) is an oral antiepileptic drug and is available as white film-coated 500 mg tablets and as a white to off-white granular powder for oral solution in packets of 500 mg. The chemical name of vigabatrin, a racemate consisting of two enantiomers, is (±) 4-amino-5-hexenoic acid. The molecular formula is C 6 H 11 NO 2 and the molecular weight is 129.16. It has the following structural formula: Vigabatrin is a white to off-white powder which is freely soluble in water, slightly soluble in methyl alcohol, very slightly soluble in ethyl alcohol and chloroform, and insoluble in toluene and hexane. The pH of a 1% aqueous solution is about 6.9. The n-octanol/water partition coefficient of vigabatrin is about 0.011 (log P=- 1.96) at physiologic pH. Vigabatrin melts with decomposition in a 3-degree range within the temperature interval of 171ºC to 176ºC. The dissociation constants (pK a ) of vigabatrin are 4 and 9.7 at room temperature (25ºC). Each SABRIL tablet contains 500 mg of vigabatrin. The inactive ingredients are hydroxypropyl methylcellulose, magnesium stearate, microcrystalline cellulose, polyethylene glycols, povidone, sodium starch glycolate, and titanium dioxide. SABRIL for oral solution is available as a white to off-white granular powder. Each packet contains 500 mg of vigabatrin. The inactive ingredient is povidone. The chemical structure of vigabatrin.
Mechanism of action
12.1 Mechanism of Action The precise mechanism of vigabatrin’s anti-seizure effect is unknown, but it is believed to be the result of its action as an irreversible inhibitor of γ-aminobutyric acid transaminase (GABA-T), the enzyme responsible for the metabolism of the inhibitory neurotransmitter GABA. This action results in increased levels of GABA in the central nervous system. No direct correlation between plasma concentration and efficacy has been established. The duration of drug effect is presumed to be dependent on the rate of enzyme re-synthesis rather than on the rate of elimination of the drug from the systemic circulation.
How supplied
16.1 How Supplied SABRIL 500 mg tablets are white, film-coated, oval, biconvex, scored on one side, and debossed with OV 111 on the other. They are supplied as bottles of 100 (NDC 67386-111-01). SABRIL for oral solution is available as 500 mg packets containing a white to off-white granular powder. They are supplied in packages of 50 (NDC 67386-211-65). The oral syringes are provided separately by the pharmacy.
Storage
16.2 Storage and Handling Store at 20°C to 25°C (68°F to 77°F). See USP controlled room temperature.
Patient information
Advise patients and caregivers to read the FDA-approved patient labeling ( Medication Guide and Instructions for Use ). Administration Instructions for SABRIL for oral solution Physicians should confirm that caregivers(s) understand how to mix SABRIL for oral solution and to administer the correct dose to their infants and pediatric patients [see Dosage and Administration ( 2.5 )]. Permanent Vision Loss Inform patients and caregivers of the risk of permanent vision loss, particularly loss of peripheral vision, from SABRIL, and the need for monitoring vision [see Warnings and Precautions ( 5.1 ) ] . Monitoring of vision, including assessment of visual fields and visual acuity, is recommended at baseline (no later than 4 weeks after starting SABRIL), at least every 3 months while on therapy, and about 3-6 months after discontinuation of therapy. In patients for whom vision testing is not possible, treatment may continue without recommended testing according to clinical judgment with appropriate patient or caregiver counseling. Patients or caregivers should be informed that if baseline or subsequent vision is not normal, SABRIL should only be used if the benefits of SABRIL treatment clearly outweigh the risks of additional vision loss. Advise patients and caregivers that vision testing may be insensitive and may not detect vision loss before it is severe. Also advise patients and caregivers that if vision loss is documented, such loss is irreversible. Ensure that both of these points are understood by patients and caregivers. Patients and caregivers should be informed that if changes in vision are suspected, they should notify their physician immediately. Vigabatrin REMS Program SABRIL is available only through a restricted program called the Vigabatrin REMS Program [see Warnings and Precautions ( 5.2 )] . Inform patients/caregivers of the following: Patients/caregivers must be enrolled in the program. SABRIL is only available through pharmacies that are enrolled in the Vigabatrin REMS Program. MRI Abnormalities in Infants Inform caregiver(s) of the possibility that infants may develop an abnormal MRI signal of unknown clinical significance [see Warnings and Precautions ( 5.3 ) ] . Suicidal Thinking and Behavior Counsel patients, their caregiver(s), and families that AEDs, including SABRIL, may increase the risk of suicidal thoughts and behavior. Also advise patients and caregivers of the need to be alert for the emergence or worsening of symptoms of depression, any unusual changes in mood or behavior, or the emergence of suicidal thoughts, behavior, or thoughts of self-harm. Behaviors of concern should be reported immediately to healthcare providers [see Warnings and Precautions ( 5.5 )]. Pregnancy Advise pregnant women and women of child-bearing potential that the use of SABRIL during pregnancy can cause fetal harm which may occur early in pregnancy before many women know they are pregnant. Instruct patients to notify their physician if they become pregnant or intend to become pregnant during therapy. Advise patients that there is a pregnancy exposure registry that collects information about the safety of antiepileptic drugs during pregnancy [see Use in Specific Populations ( 8.1 )] . Nursing Counsel patients that SABRIL is excreted in breast milk. Because of the potential for serious adverse reactions in nursing infants from SABRIL, breastfeeding is not recommended. If a decision is made to breastfeed, nursing mothers should be counseled to observe their infants for signs of vision loss, sedation and poor sucking [see Use in Specific Populations ( 8.2 )]. Withdrawal of SABRIL Therapy Instruct patients and caregivers not to suddenly discontinue SABRIL therapy without consulting with their healthcare provider. As with all AEDs, withdrawal should be gradual [see Warnings and Precautions ( 5.6 )] . Manufactured by: Patheon Cincinnati, OH 45237, U.S.A. For: Lundbeck Deerfield, IL 60015, U.S.A. SABRIL is a registered trademark of Lundbeck
Label text from the FDA structured product label by Lundbeck Pharmaceuticals LLC (revised Oct 20, 2021). Long sections are shortened; the complete label is on DailyMed.
Active ingredients
- Vigabatrin in 2 products
Sabril NDC products (2)
| NDC | Strength & form | Labeler | Type |
|---|---|---|---|
| 67386-111 | Vigabatrin 500 mg/1 Tablet, Film Coated | Lundbeck Pharmaceuticals LLC | NDA |
| 67386-211 | Vigabatrin 50 mg/mL Powder, For Solution | Lundbeck Pharmaceuticals LLC | NDA |
Sabril recalls
- D-1142-2023 Sep 6, 2023 · Class III · Completed
Cross contamination with other products
Frequently asked questions
What is Sabril used for?
1 INDICATIONS AND USAGE SABRIL is indicated for the treatment of: Refractory Complex Partial Seizures as adjunctive therapy in patients 2 years of age and older who have responded inadequately to several alternative treatments; SABRIL is not indicated as a first line agent ( 1.1 ) Infantile Spasms - monotherapy in infants 1 month to 2 years of age for whom the potential benefits outweigh the…
What are the side effects of Sabril?
The following serious and otherwise important adverse reactions are described elsewhere in labeling: Permanent Vision Loss [see BOXED WARNING and Warnings and Precautions ( 5.1 ) ] Magnetic Resonance Imaging (MRI) Abnormalities in Infants [see Warnings and Precautions ( 5.3 ) ] Neurotoxicity [see Warnings and Precautions ( 5.4 )] Suicidal Behavior and Ideation [see Warnings and Precautions ( 5.5… See the full label for the complete list.
Who makes Sabril?
Sabril is listed by 1 labeler in the FDA NDC directory, including Lundbeck Pharmaceuticals LLC.
Has Sabril been recalled?
The FDA enforcement database lists 1 recall for Sabril, most recently D-1142-2023 (class iii): Cross contamination with other products