ZAVESCA
Clinical safety rating: caution
Comprehensive clinical and safety monograph for ZAVESCA (ZAVESCA).
Inhibits glucosylceramide synthase, reducing synthesis of glycosphingolipids including glucocerebroside.
| Metabolism | Primarily metabolized by CYP3A4; minor involvement of CYP2D6 and CYP2C19. |
| Excretion | Renal (predominantly): 70% unchanged, fecal: 20% as metabolites, biliary: minor. |
| Half-life | 6-7 hours; in patients with hepatic impairment, up to 12-15 hours. |
| Protein binding | 60% bound, primarily to albumin. |
| Volume of Distribution | 2-5 L/kg, indicating extensive tissue distribution. |
| Bioavailability | Oral: ~97% (highly absorbed), with food decreasing rate but not extent. |
| Onset of Action | Oral: 2-4 weeks for symptomatic improvement in Gaucher disease; 6-12 months for neurological stabilization in Niemann-Pick type C. |
| Duration of Action | 12 hours (dosing interval); clinical effect persists with continued therapy. |
| Molecular Weight | 481.84 |
100 mg orally three times daily.
| Dosage form | CAPSULE |
| Renal impairment | For GFR 50-70 mL/min/1.73m2: 100 mg twice daily; for GFR 30-50: 100 mg once daily; for GFR <30: not recommended. |
| Liver impairment | Child-Pugh A: no adjustment; Child-Pugh B: reduce dose to 100 mg twice daily; Child-Pugh C: not recommended. |
| Pediatric use | Weight-based dosing: <47 kg: 100 mg three times daily; ≥47 kg: 200 mg three times daily (adult dose). |
| Geriatric use | No specific adjustment; monitor renal function due to age-related decline. |
| 1st trimester | Based on animal studies and limited human data, ZAVESCA (miglustat) may cause fetal harm. Use only if potential benefit justifies risk to fetus. |
| 2nd trimester | Same as T1. There are no adequate and well-controlled studies in pregnant women. Avoid use unless clearly needed. |
| 3rd trimester | Same as T1 and T2. Potential for adverse effects on fetal growth and development. |
Clinical note
Comprehensive clinical and safety monograph for ZAVESCA (ZAVESCA).
| Placental transfer | Miglustat crosses the placenta in animal studies. Human data are lacking but transfer is likely due to low molecular weight and high water solubility. |
| Breastfeeding | ZAVESCA is excreted into animal milk. Due to potential for serious adverse reactions in nursing infants, breastfeeding is not recommended during treatment and for at least 2 weeks after the last dose. |
■ FDA Black Box Warning
None
| Serious Effects |
Hypersensitivity to miglustat or any excipientsBreastfeeding (due to potential infant toxicity)
| Precautions | Peripheral neuropathy, Tremor, Gastrointestinal disturbances, Decreased fertility in males, Monitor for tremors and neuropathy |
| Food/Dietary | Grapefruit and grapefruit juice may increase miglustat plasma concentrations and should be avoided. No other significant food interactions are known. Zavesca can be taken with or without food. |
| Clinical Pearls |
Loading safety data…
| Lactation Rating | L5 - Contraindicated |
| Teratogenic Risk | ZAVESCA (miglustat) is classified as FDA Pregnancy Category C. In animal studies, miglustat caused embryofetal toxicity including reduced fetal weight, increased resorptions, and skeletal variations at maternal toxic doses. There are no adequate and well-controlled studies in pregnant women. Potential fetal risk cannot be ruled out, especially during first trimester organogenesis. Use only if benefit outweighs risk. |
| Fetal Monitoring | Monitor fetal growth and development via ultrasound. Assess for signs of oligohydramnios if used in second/third trimester. Monitor maternal neurological symptoms (tremor, paresthesia) and gastrointestinal tolerability. Periodic liver function tests and blood counts are recommended. |
| Fertility Effects | In animal studies, miglustat did not impair fertility in male or female rats. There are no human data on fertility effects. Potential effects on human fertility are unknown. |
| Zavesca (miglustat) is a glucosylceramide synthase inhibitor used for mild to moderate type 1 Gaucher disease when enzyme replacement therapy is not suitable. Monitor for peripheral neuropathy, tremors, and gastrointestinal side effects. Dose adjustment for renal impairment: CrCl 30-50 mL/min: reduce to 100 mg BID; CrCl <30 mL/min: not recommended. Obtain baseline neurological exam and repeat annually. |
| Patient Advice | Take Zavesca exactly as prescribed, usually three times a day with or without food. · Do not stop taking this medication without consulting your doctor. · Notify your doctor if you experience new or worsening tremors, numbness, tingling, or weakness in your arms or legs. · Common side effects include diarrhea, weight loss, and abdominal discomfort; these may improve over time. · Avoid grapefruit and grapefruit juice during treatment as it may affect how the drug works. · Report any signs of infection such as fever or persistent cough. · Women of childbearing potential should use effective contraception during treatment and for 3 months after the last dose. · Do not breastfeed while taking Zavesca. |