Vigadrone (vigabatrin) for Complex Partial Seizures (CPS)

What is Vigadrone, and how does it work?

Vigadrone is a prescription medicine used along with other treatments to treat adults and children 10 years and older with complex partial seizures (CPS) if:

The CPS does not respond well enough to several other treatments, and
You and your healthcare provider decide the possible benefit of taking
Vigadrone is more important than the risk of vision loss.

Vigadrone should not be the first medicine used to treat CPS.

Vigadrone is also used to treat babies 1 month to 2 years of age who have infantile spasms (IS) if you and your healthcare provider decide the possible benefits of taking
Vigadrone are more important than the possible risk of vision loss.

What are the side effects of Vigadrone?

Vigadrone can cause serious side effects , including

sleepiness and tiredness.
Vigadrone may cause your baby to be sleepy. Sleepy babies may have a harder time suckling and feeding, or may be irritable.
weight gain that happens without swelling

The following serious side effects happen in adults. It is not known if these side effects also happen in babies who take
Vigadrone.

low red blood cell counts (anemia)
nerve problems. Symptoms of a nerve problem can include numbness and tingling in your toes or feet. It is not known if nerve problems will go away after you stop taking
Vigadrone.
swelling

If you or your child has CPS,
Vigadrone may make certain types of seizures worse. Tell your healthcare provider right away if your (or your child’s ) seizures get worse.

The most common side effects of
Vigadrone in adults include:

problems walking or feeling uncoordinated
feeling dizzy
shaking (tremor)
joint pain
memory problems and not thinking clearly
eye problems: blurry vision, double vision and eye movements that you cannot control

The most common side effects of
Vigadrone in children 10 to 16 years of age include:

Also expect side effects like those seen in adults

If you are giving
Vigadrone to your baby for IS:

Vigadrone may make certain types of seizures worse. You should tell your baby’s healthcare provider right away if your baby’s seizures get worse. Tell your baby’s healthcare provider if you see any changes in your baby’s behavior.

The most common side effects of
Vigadrone in babies include:

sleepiness – Vigadrone may cause your baby to be sleepy. Sleepy babies may have a harder time suckling and feeding, or may be irritable.
swelling in the bronchial tubes (bronchitis)
ear infection
irritability

Tell your healthcare provider if you or your child have any side effect that bothers you or that does not go away. These are not all the possible side effects of
Vigadrone.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

WARNING

PERMANENT VISION LOSS

Vigadrone can cause permanent bilateral concentric visual field constriction,
including tunnel vision that can result in disability. In some cases, Vigadrone
also can damage the central retina and may decrease visual acuity.
The onset of vision los s from
Vigadrone 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
Vigadrone 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
Vigadrone), at least every 3 months during therapy, and about 3 to 6 months after the discontinuation of therapy.
Once detected, vision loss due to
Vigadrone 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 los s is documented.
Risk of new or worsening vision loss continues as long as
Vigadrone is used. It is possible that vision loss can worsen despite discontinuation of
Vigadrone.
Because of the risk of vision loss, Vigadrone should be withdrawn from patients with refractory complex partial seizures who fail to show substantial clinical benefit within 3 months of initiation and within 2 to 4 weeks of initiation for patients with infantile spasms, or sooner if treatment failure becomes obvious . Patient response to and continued need for
Vigadrone should be periodically reassessed.
Vigadrone 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.
Vigadrone 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
Vigadrone cons is tent with
clinical objectives.
Because of the risk of permanent vision loss,
Vigadrone is available only through a restricted program under a Risk Evaluation
and Mitigation Strategy (REMS) called the Vigabatrin REMS Program. Further information is available at www.vigabatrinREMS.com or call 1-866-244-8175.

Does Vigadrone cause addiction or withdrawal symptoms?

Drug Abuse And Dependence

Controlled Substance

Vigabatrin is not a controlled substance.

Abuse

Vigabatrin did not produce adverse events or overt behaviors associated with abuse when administered to humans or animals.
It is not possible to predict the extent to which a CNS active drug will be misused, diverted, and/or abused once marketed.
Consequently, physicians should carefully evaluate patients for history of drug abuse and follow such patients closely, observing them for signs of misuse or abuse of vigabatrin (e.g., incrementation of dose, drug-seeking behavior).

Dependence

Following chronic administration of vigabatrin to animals, there were no
apparent withdrawal signs upon drug discontinuation.
However, as with all AEDs, vigabatrin should be withdrawn gradually to
minimize increased seizure frequency.

What is the dosage for Vigadrone?

Important Dosing And Administration Instructions

Dosing

Use the lowest dosage and shortest exposure to Vigadrone consistent with
clinical objectives.
The Vigadrone dosing regimen depends on the indication, age group,
weight, and dosage form (tablets or powder for oral solution). Patients with
impaired renal function require dose adjustment.
Monitoring of Vigadrone plasma concentrations to optimize therapy is not helpful.

Administration

Vigadrone is given orally with or without food.
Vigadrone powder for oral solution should be mixed with water prior to
administration. 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 Vigadrone, the dose should be
gradually reduced.

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 Vigadrone 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,
vigabatrin was tapered by decreasing the daily dose 1000 mg/day on a weekly
basis until discontinued.

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 kg350 mg1,050 mgGreater than 15 kg to 20 kg450 mg1,300 mgGreater than 20 kg to 25 kg500 mg1,500 mgGreater than 25 kg to 60 kg500 mg2,000 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, Vigadrone 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.
In a controlled study in pediatric patients with complex partial
seizures, vigabatrin was tapered by decreasing the daily dose by one third
every week for three weeks.

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).
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/dayMaximum Dose
150 mg/kg/day31.5 mL twice daily4.5 mL twice daily42 mL twice daily6 mL twice daily52.5 mL twice daily7.5 mL twice daily63 mL twice daily9 mL twice daily73.5 mL twice daily10.5 mL twice daily84 mL twice daily12 mL twice daily94.5 mL twice daily13.5 mL twice daily105 mL twice daily15 mL twice daily115.5 mL twice daily16.5 mL twice daily126 mL twice daily18 mL twice daily136.5 mL twice daily19.5 mL twice daily147 mL twice daily21 mL twice daily157.5 mL twice daily22.5 mL twice daily168 mL twice daily24 mL twice daily

In patients with infantile spasms, Vigadrone 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.
In a controlled clinical study in patients with infantile spasms,
vigabatrin was tapered by decreasing the daily dose at a rate of 25 mg/kg to
50 mg/kg every 3 to 4 days.

Patients With Renal Impairment

Vigadrone is primarily eliminated through the kidney.

Infants

Information about how to adjust the dose in infants with renal impairment is unavailable.

Adult And Pediatric Patients 2 Years And Older

Mild renal impairment (CLcr >50 to 80 mL/min): dose should be decreased by 25%
Moderate renal impairment (CLcr >30 to 50 mL/min): dose should be decreased by 50%
Severe renal impairment (CLcr >10 to 30 mL/min): dose should be decreased by 75%

CLcr in mL/min may be estimated from serum creatinine (mg/dL) using the following formulas:

Patients 2 to <12 years old: CLcr (mL/min/1.73 m²) = (K × Ht) / Scr height (Ht) in cm; serum creatinine (Scr) in mg/dL K (proportionality constant): Female Child (<12 years): K=0.55; Male Child (<12 years): K=0.70
Adult and pediatric patients 12 years or older: CLcr (mL/min) = [140–age (years)] × weight (kg) / [72 × serum creatinine (mg/dL)] (×0.85 for female patients)

The effect of dialysis on
Vigadrone clearance has not been adequately studied.

What drugs interact with Vigadrone?

Antiepileptic Drugs

Phenytoin

Although phenytoin dose
adjustments are not routinely required, dose adjustment of phenytoin should be
considered if clinically indicated, since Vigadrone may cause a moderate
reduction in total phenytoin plasma levels.

Clonazepam

Vigadrone may moderately increase the Cmax of clonazepam resulting in an
increase of clonazepam-associated adverse reactions.

Other AEDs

There are no clinically significant pharmacokinetic interactions between
vigabatrin 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.

Oral Contraceptives

Vigadrone is unlikely to affect the efficacy of steroid oral contraceptives.

Drug-Laboratory Test Interactions

Vigadrone 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
Vigadrone may preclude the use of these markers, especially ALT, to detect early hepatic injury.
Vigadrone 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).

Latest Neurology News

Trending on MedicineNet

Is Vigadrone safe to use while pregnant or breastfeeding?

In pregnant women and women of child-bearing potential, the use of
Vigadrone during pregnancy can cause fetal harm, which may occur early in pregnancy before many women know they are pregnant.
Notify your physician if you become pregnant or intend to become pregnant during therapy.
There is a pregnancy exposure registry that collects information about the safety of antiepileptic drugs during pregnancy.
Vigadrone is excreted in breast milk.
Because of the potential for serious adverse reactions in nursing infants from
Vigadrone, 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.