Rufinamide: Package Insert and Label Information (Page 2 of 4)

Discontinuation in Controlled Clinical Studies

In controlled, double-blind, adjunctive clinical studies, 9% of pediatric and adult patients receiving rufinamide as adjunctive therapy and 4% receiving placebo discontinued as a result of an adverse reaction. The adverse reactions most commonly leading to discontinuation of rufinamide (>1%) used as adjunctive therapy were generally similar in adults and pediatric patients.

In pediatric patients (ages 4 to less than 17 years) double-blind adjunctive clinical studies, 8% of patients receiving rufinamide as adjunctive therapy (at the recommended dose of 45 mg/kg per day) and 2% receiving placebo discontinued as a result of an adverse reaction. The adverse reactions most commonly leading to discontinuation of rufinamide (>1%) used as adjunctive therapy are presented in Table 4.

Table 4: Most Common Adverse Reactions Leading to Discontinuation in Pediatric Patients (Ages 4 to less than 17 years) in Pooled Double-Blind Adjunctive Trials

Adverse Reaction

Rufinamide

(N=187)%

Placebo

(N=182)%

Convulsion

2

1

Rash

2

1

Fatigue

2

0

Vomiting

1

0

In adult double-blind, adjunctive clinical studies, 10% of patients receiving rufinamide as adjunctive therapy (at doses up to 3,200 mg per day) and 6% receiving placebo discontinued as a result of an adverse reaction. The adverse reactions most commonly leading to discontinuation of rufinamide (>1%) used as adjunctive therapy are presented in Table 5.

Table 5: Most Common Adverse Reactions Leading to Discontinuation in Adult Patients in Pooled Double-Blind Adjunctive Trials

Adverse Reaction

Rufinamide

(N=823)

%

Placebo

(N=376)

%

Dizziness

3

1

Fatigue

2

1

Headache

2

1

Nausea

1

0

Ataxia

1

0

Pediatric Patients ages 1 to less than 4 years

In a multicenter, parallel group, open-label study comparing rufinamide (45 mg/kg per day) adjunctive treatment (n=25) to the adjunctive treatment with an AED of the investigator’s choice (n=11) in pediatric patients (1 year to less than 4 years of age) with inadequately controlled Lennox-Gastaut Syndrome, the adverse reaction profile was generally similar to that observed in adults and pediatric patients 4 years of age and older treated with rufinamide. Adverse reactions that occurred in at least 2 (8 %) rufinamide-treated patients and with a higher frequency than in the AED comparator group were: vomiting (24%), somnolence (16%), bronchitis (12%), constipation (12%), cough (12%), decreased appetite (12%), rash (12%), otitis media (8%), pneumonia (8%), decreased weight (8%), gastroenteritis (8%), nasal congestion (8%), and pneumonia aspiration (8%).

Other Adverse Reactions Observed During Clinical Trials

Rufinamide has been administered to 1,978 individuals during all epilepsy clinical trials (placebo-controlled and open-label). Adverse reactions occurring during these studies were recorded by the investigators using terminology of their own choosing. To provide a meaningful estimate of the proportion of patients having adverse reactions, these events were grouped into standardized categories using the MedDRA dictionary. Adverse events occurring at least three times and considered possibly related to treatment are included in the System Organ Class listings below. Terms not included in the listings are those already included in the tables above, those too general to be informative, those related to procedures, and terms describing events common in the population. Some events occurring fewer than 3 times are also included based on their medical significance. Because the reports include events observed in open-label, uncontrolled observations, the role of rufinamide in their causation cannot be reliably determined.

Events are classified by body system and listed in order of decreasing frequency as follows: frequent adverse events — those occurring in at least 1/100 patients; infrequent adverse events -those occurring in 1/100 to 1/1,000 patients; rare — those occurring in fewer than 1/1,000 patients.

Blood and Lymphatic System Disorders: Frequent: anemia. Infrequent: lymphadenopathy, leukopenia, neutropenia, iron deficiency anemia, thrombocytopenia.

Cardiac Disorders: Infrequent: bundle branch block right, atrioventricular block first degree.

Metabolic and Nutritional Disorders: Frequent: decreased appetite, increased appetite.

Renal and Urinary Disorders: Frequent: pollakiuria. Infrequent: urinary incontinence, dysuria, hematuria, nephrolithiasis, polyuria, enuresis, nocturia, incontinence.

6.2 Postmarketing Experience

The following adverse reactions have been identified during post approval use of rufinamide. 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.

Dermatologic: Stevens-Johnson syndrome and other serious skin rashes with mucosal involvement.

7 DRUG INTERACTIONS

7.1 Effects of Rufinamide on other AEDs

Population pharmacokinetic analysis of average concentration at steady state of carbamazepine, lamotrigine, phenobarbital, phenytoin, topiramate, and valproate showed that typical rufinamide Cavss levels had little effect on the pharmacokinetics of other AEDs. Any effects, when they occur, have been more marked in the pediatric population.

Table 6 summarizes the drug-drug interactions of rufinamide with other AEDs.

Table 6: Summary of drug-drug interactions of rufinamide with other antiepileptic drugs

AED

Co- administered

Influence of Rufinamide on AED concentrationa)

Influence of AED on Rufinamide concentration

Carbamazepine

Decrease by 7 to 13%b)

Decrease by 19 to 26%

Dependent on dose of carbamazepine

Lamotrigine

Decrease by 7 to 13% b)

No Effect

Phenobarbital

Increase by 8 to 13% b)

Decrease by 25 to 46% c), d)

Independent of dose or concentration of phenobarbital

Phenytoin

Increase by 7 to 21%b)

Decrease by 25 to 46% c),d)

Independent of dose or concentration of phenytoin

Topiramate

No Effect

No Effect

Valproate

No Effect

Increase by <16 to 70% c)

Dependent on concentration of valproate

Primidone

Not Investigated

Decrease by 25 to 46% c), d)

Independent of dose or concentration of primidone

Benzodiazepinese)

Not Investigated

No Effect

a) Predictions are based on rufinamide concentrations at the maximum recommended dose of rufinamide.
b) Maximum changes predicted to be in pediatric patients and in adult patients who achieve significantly higher levels of rufinamide, as the effect of rufinamide on these AEDs is concentration-dependent.
c) Larger effects in pediatric patients at high doses/concentrations of AEDs.
d) Phenobarbital, primidone and phenytoin were treated as a single covariate (phenobarbital-type inducers) to examine the effect of these agents on rufinamide clearance.
e) All compounds of the benzodiazepine class were pooled to examine for ‘class effect’ on rufinamide clearance.

Phenytoin: The decrease in clearance of phenytoin estimated at typical levels of rufinamide (Cavss 15 mcg/mL) is predicted to increase plasma levels of phenytoin by 7 to 21%. As phenytoin is known to have non-linear pharmacokinetics (clearance becomes saturated at higher doses), it is possible that exposure will be greater than the model prediction.

7.2 Effects of other AEDs on Rufinamide

Potent cytochrome P450 enzyme inducers, such as carbamazepine, phenytoin, primidone, and phenobarbital, appear to increase the clearance of rufinamide (see Table 6). Given that the majority of clearance of rufinamide is via a non-CYP-dependent route, the observed decreases in blood levels seen with carbamazepine, phenytoin, phenobarbital, and primidone are unlikely to be entirely attributable to induction of a P450 enzyme. Other factors explaining this interaction are not understood. Any effects, where they occurred, were likely to be more marked in the pediatric population.

Valproate

Patients stabilized on rufinamide before being prescribed valproate should begin valproate therapy at a low dose, and titrate to a clinically effective dose. Similarly, patients on valproate should begin at a rufinamide dose lower than 10 mg/kg per day (pediatric patients) or 400 mg per day (adults) [see Dosage and Administration (2.5), Clinical Pharmacology (12.3)].

7.3 Effects of Rufinamide on Hormonal Contraceptives

Female patients of childbearing age should be warned that the concurrent use of rufinamide with hormonal contraceptives may render this method of contraception less effective. Additional non-hormonal forms of contraception are recommended when using rufinamide [see Use in Specific Populations (8.3), Clinical Pharmacology (12.3) and Patient Counseling Information (17)].

8 USE IN SPECIFIC POPULATIONS

8.1 Pregnancy

Pregnancy Exposure Registry

There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to AEDs, such as rufinamide, during pregnancy. Encourage women who are taking Rufinamide during pregnancy to enroll in the North American Antiepileptic Drug (NAAED) Pregnancy Registry by calling 1-888-233-2334 or visiting http://www.aedpregnancyregistry.org.

Risk Summary

There are no adequate data on the developmental risks associated with use of rufinamide in pregnant women. In animal reproduction studies, oral administration of rufinamide resulted in developmental toxicity in pregnant rats and rabbits at clinically relevant doses [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

Oral administration of rufinamide (0, 20, 100, or 300 mg/kg/day) to pregnant rats throughout organogenesis resulted in decreased fetal weight and increased incidence of fetal skeletal abnormalities at 100 and 300 mg/kg/day, which were associated with maternal toxicity. The maternal plasma exposure (AUC) at the no- adverse effect dose (20 mg/kg/day) for developmental toxicity was less than that in humans at the maximum recommended human dose (MRHD) of 3200 mg/day.

Oral administration of rufinamide (0, 30, 200, or 1000 mg/kg/day) to pregnant rabbits throughout organogenesis resulted in embryofetal death, decreased fetal body weight, and increased incidence of fetal visceral and skeletal abnormalities at doses of 200 and 1000 mg/kg/day. The high dose (1000 mg/kg/day) was associated with abortion. Plasma exposure (AUC) at the no-adverse effect dose (30 mg/kg/day) was less than that in humans at the MRHD.

When rufinamide was orally administered (0, 5, 30, or 150 mg/kg/day) to pregnant rats throughout pregnancy and lactation, decreased offspring growth and survival were observed at all doses tested. A no-effect dose for adverse effects on pre- and postnatal development was not established. At the lowest dose tested (5 mg/kg/day), plasma exposure (AUC) was less than that in humans at the MRHD.

8.2 Lactation

Risk Summary

There are no data on the presence of rufinamide in human milk, the effects on the breastfed infant, or the effects of the drug on milk production.

The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for rufinamide and any potential adverse effects on the breastfed infant from rufinamide or from the underlying maternal condition.

8.3 Females and Males of Reproductive Potential

Contraception

Use of rufinamide may reduce the effectiveness of hormonal contraceptives containing ethinyl estradiol or norethindrone. Advise women of reproductive potential taking rufinamide who are using a contraceptive containing ethinyl estradiol and norethindrone to use an additional non-hormonal form of contraception [see Drug Interactions (7.3) and Clinical Pharmacology (12.3)].

Infertility

The effect of rufinamide on fertility in humans has not been established. Oral administration of rufinamide (20, 60, 200, and 600 mg/kg/day) to male and female rats prior to mating, during mating, and during early gestation (females only) resulted in the impairment of fertility at all dose levels tested. The no-effect dose was not established. The plasma exposure level at 20 mg/kg was approximately 0.2 times the human plasma AUC at the MRHD [see Nonclinical Toxicology (13.1)].

DrugInserts.com provides trustworthy package insert and label information about marketed drugs as submitted by manufacturers to the US Food and Drug Administration. Package information is not reviewed or updated separately by DrugInserts.com. Every individual package label entry contains a unique identifier which can be used to secure further details directly from the US National Institutes of Health and/or the FDA.

As the leading independent provider of trustworthy medication information, we source our database directly from the FDA's central repository of drug labels and package inserts under the Structured Product Labeling standard. Our material is not intended as a substitute for direct consultation with a qualified health professional.

Terms of Use | Copyright © 2023. All Rights Reserved.