Gauchers Disease Agents
Miglustat should be administered orally at regular intervals.
Miglustat may be taken with or without food.
visual impairment / Early / 17.0-17.0
constipation / Delayed / 8.0-8.0
peripheral neuropathy / Delayed / 8.0-8.0
thrombocytopenia / Delayed / 6.0-7.0
migraine / Early / 6.0-6.0
infertility / Delayed / Incidence not known
diarrhea / Early / 85.0-99.0
weight loss / Delayed / 39.0-67.0
abdominal pain / Early / 18.0-67.0
flatulence / Early / 29.0-50.0
tremor / Early / 11.0-30.0
nausea / Early / 8.0-22.0
headache / Early / 21.0-22.0
weakness / Early / 17.0-17.0
vomiting / Early / 4.0-11.0
muscle cramps / Delayed / 4.0-11.0
dizziness / Early / 8.0-11.0
xerostomia / Early / 8.0-8.0
back pain / Delayed / 8.0-8.0
anorexia / Delayed / 7.0-7.0
dyspepsia / Early / 7.0-7.0
paresthesias / Delayed / 7.0-7.0
menstrual irregularity / Delayed / 6.0-6.0
spermatogenesis inhibition / Delayed / Incidence not known
Common Brand Names
Glucosylceramide synthase inhibitor
Used for mild to moderate type 1 Gaucher disease
Adverse reactions are common (e.g., diarrhea, weight loss, tremor)
Dosage And Indications
100 mg PO 3 times per day at regular intervals. The dosage may be reduced to 100 mg PO once or twice daily if adverse reactions (e.g., diarrhea or tremor) are not tolerated.
Specific guidelines for dosage adjustments in hepatic impairment are not available; it appears that no dosage adjustments are needed.Renal Impairment
CrCl more than 70 mL/minute: No dosage adjustment needed.
CrCl 50 to 70 mL/minute: 100 mg PO twice daily.
CrCl 30 to 49.9 mL/minute: 100 mg PO once daily.
CrCl less than 30 mL/minute: Not recommended.
Imiglucerase: (Major) Combination therapy with miglustat and imiglucerase is not indicated for Gaucher disease. Miglustat may increase the clearance of imiglucerase, although the clinical significance of this interaction is not yet known.
Miglustat/Zavesca Oral Cap: 100mg
300 mg/day PO.Geriatric
300 mg/day PO.Adolescents
Safety and efficacy have not been established.Children
Safety and efficacy have not been established.
Mechanism Of Action
Miglustat is a competitive and reversible inhibitor of the enzyme glucosylceramide synthase, the initial enzyme responsible in the synthesis of glucosylceramide. Chemically, miglustat is a synthetic derivative of an N-alkylated imino sugar, a synthetic analogue of D-glucose. In type 1 Gaucher disease, patients are deficient in the enzyme glucocerebrosidase which is responsible for degradation of glucosylceramide. Glucosylceramide arises mainly from the breakdown of red and white blood cells and turnover of lipids during CNS myelin sheath formation. Rather than replacing glucocerebrosidase, miglustat acts as a substrate reducer (by inhibiting glucosylceramide synthase) and allows the available glucocerebrosidase enzyme to be more effective. Clinically, the use of miglustat has improved liver and spleen volume, hemoglobin concentrations and platelet counts in patients with type 1 Gaucher disease.
Miglustat is administered orally.
Miglustat does not bind to plasma proteins, but instead distributes into extravascular tissues with a mean volume of distribution of 83 to 105 L. Pharmacokinetics are dose proportional and plasma concentrations decline bi-exponentially, with a short distribution phase and a longer elimination phase. The half life is roughly 6 to 7 hours, with steady state achieved in 1.5 days. Miglustat is primarily eliminated as the parent drug in the urine; there is no evidence of hepatic metabolism. In patients with adequate renal function, repeat dosing does not result in accumulation or alteration in pharmacokinetics.
After a 100 mg oral dose, Tmax ranges from 2 to 2.5 hours in type 1 Gaucher disease patients. Oral bioavailability from the capsule formulation is 97% of that achieved with the oral solution (oral solution is not commercially available in the US). Administration of miglustat with food prolongs the rate but does not affect the extent of absorption; miglustat may be taken with or without food.
Pregnancy And Lactation
Miglustat has not been evaluated in pregnant women. Available data from postmarketing case reports are insufficient to assess a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes. In animal reproduction studies, maternal death and decreased body weight gain were observed in rabbits orally dosed with miglustat during organogenesis at doses with exposures less than the human therapeutic systemic exposure. Decreased live births and decreased fetal weight were observed in rats orally dosed with miglustat prior to mating and during organogenesis at doses with exposures at least 2 times the human therapeutic systemic exposure. Dystocia and delayed parturition were also observed. According to the to FDA-approved product labeling, miglustat should be used during pregnancy only if the potential benefit justifies the potential risk to the mother and fetus. No reports of exposure to miglustat during human pregnancy are found in the medical literature. A prospective, surveillance study, reported on the 5 year use of miglustat after its approval in Europe. The mean age of participants at baseline was 46.1 (SD 16.5) years. In this report, 1 woman of childbearing age discontinued miglustat therapy for a planned pregnancy. Imiglucerase has been suggested, based on the data available, as an agent for consideration for the treatment of Gaucher disease during pregnancy.
It is not known whether miglustat is excreted into the milk of breast-feeding women; however, based on the physical properties of miglustat, it is likely to be present in breast milk. Because of the potential for serious adverse reactions in breast-feeding infants, breast-feeding is not recommended. Imiglucerase has been suggested as an enzyme-replacement treatment option, based on limited data from case studies and breast milk concentration data. Consider the benefits of breast-feeding, the risk of potential infant drug exposure, and the risk of an untreated or inadequately treated condition. If a breast-feeding infant experiences an adverse effect related to a maternally administered drug, healthcare providers are encouraged to report the adverse effect to the FDA.