Vigabatrin
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From MedlinePlus, U.S. National Library of Medicine
Boxed warning
WARNING: PERMANENT VISION LOSS VIGAFYDE can cause permanent bilateral concentric visual field constriction, including tunnel vision that can result in disability. In some cases, VIGAFYDE also can damage the central retina and may decrease visual acuity [see Warnings and Precautions ( 5.1 )]. The onset of vision loss from VIGAFYDE is unpredictable, and can occur within weeks of starting treatment or sooner, or at any time after starting treatment, even after months or years. Symptoms of vision loss from VIGAFYDE 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. 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. Vision assessment is recommended at baseline (no later than 4 weeks after starting VIGAFYDE), at least every 3 months during therapy, and about 3 to 6 months after the discontinuation of therapy. Once detected, vision loss due to VIGAFYDE is not reversible. It is expected that, even with frequent monitoring, some patients will develop severe vision loss.
Consider drug discontinuation, balancing benefit and risk, if vision loss is documented. Risk of new or worsening vision loss continues as long as VIGAFYDE is used. It is possible that vision loss can worsen despite discontinuation of VIGAFYDE. Because of the risk of vision loss, VIGAFYDE should be withdrawn from patients with infantile spasms who fail to show substantial clinical benefit within 2 to 4 weeks of initiation, or sooner if treatment failure becomes obvious. Patient response to and continued need for VIGAFYDE should be periodically reassessed.
VIGAFYDE 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. VIGAFYDE 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. Use the lowest dosage and shortest exposure to VIGAFYDE consistent with clinical objectives [see Dosage and Administration ( 2.1 )].
Because of the risk of permanent vision loss, VIGAFYDE is available only through a restricted program under a Risk Evaluation and Mitigation Strategy (REMS) called the Vigabatrin REMS [see Warnings and Precautions ( 5.1 ) ] . Further information is available at www.vigabatrinREMS.com or call 1 -866-244-8175. WARNING:…
Anti-epileptic Agent
Dosing in kidney impairment
Renal Impairment Information about how to adjust the dose in infants with renal impairment is unavailable.
Preparation and administration
Important Dosing and Administration Instructions Dosing VIGAFYDE is a solution of 100 mg/mL of vigabatrin. VIGAFYDE is a concentrated solution as compared to other vigabatrin products. Verify strength and the dose of the product prior to prescribing, dispensing, and administering [see Dosage and Administration]. VIGAFYDE does not require additional reconstitution or dilution prior to administration.
Use the lowest dosage and shortest exposure to VIGAFYDE consistent with clinical objectives [see Warnings and Precautions]. The VIGAFYDE dosing regimen depends on weight. Monitoring of VIGAFYDE plasma concentrations to optimize therapy is not helpful. Administration Administer VIGAFYDE orally or via gastrostomy (G) tube.
Doses administered via gastrojejunal (GJ) tubes must be administered through the G-port. After G-tube administration, flush with water. VIGAFYDE can be given with or without food. 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 VIGAFYDE, the dose should be gradually reduced [see Dosage and Administration and Warnings and Precautions] .
Drug interactions
Check vigabatrin against a medication listLabel text (3 paragraphs)
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 VIGAFYDE may cause a moderate reduction in total phenytoin plasma levels [see Clinical Pharmacology ( 12.3 )]. Clonazepam VIGAFYDE may moderately increase the C max of clonazepam resulting in an increase of clonazepam-associated adverse reactions [see Clinical Pharmacology ( 12.3 )].
7.2 Drug-Laboratory Test Interactions VIGAFYDE 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 vigabatrin may preclude the use of these markers, especially ALT, to detect early hepatic injury. VIGAFYDE 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).
Contraindications
None. None ( 4 )
Pregnancy and lactation
Pregnancy
8.1 Pregnancy VIGAFYDE is indicated for treatment in patients 1 month to 2 years of age [see Indications and Usage ( 1 )]. VIGAFYDE is not approved for use in adolescents and adults. Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to AEDs, including VIGAFYDE, during pregnancy. Encourage women who are taking VIGAFYDE 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 VIGAFYDE in pregnant women. Limited available data from case reports and cohort studies pertaining to vigabatrin 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, VIGAFYDE 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 to 4% and 15 to 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…
For breastfeeding, also see LactMed (National Library of Medicine), which summarizes milk levels and infant effects.
Supply and cost
Drug shortage status
Recalls (last 24 months)
Therapeutic equivalence (Orange Book)
Price ladder
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