Dosing and uses of Elaprase (idursulfase)
Adult dosage forms and strengths
injectable solution
- 2mg/mL (as 6mg/3mL single-use vial)
Hunter Syndrome
0.5 mg/kg IV qWeek; infuse over 1-3 hr qWeek
Pediatric dosage forms and strengths
injectable solution
- 2mg/mL (as 6mg/3mL single-use vial)
Hunter Syndrome
<5 years: Safety and efficacy not established
≥5 years: 0.5 mg/kg IV qWeek; infuse over 1-3 hr
Dosing Considerations
Shown to improve walking capacity in patients aged ≥5 years
In patients aged 16 months to 5 yr, no data are available to demonstrate improvement in disease-related symptoms or long term clinical outcome; however, treatment has reduced spleen volume similarly to that of adults and children aged 5 yr and older
Elaprase (idursulfase) adverse (side) effects
>10%
Pyrexia (63%)
Headache (59%)
Arthralgia (31%)
Limb pain (28%)
Pruritus (28%)
Hypertension (25%)
Malaise (22%)
Visual disturbance (22%)
Wheezing (19%)
Abscess (16%)
Chest wall musculoskeletal pain (16%)
Musculoskeletal dysfunction (16%)
Urticaria (16%)
AE resulting from injury (13%)
Anxiety (13%)
Iirritability (13%)
Atrial abnormality (13%)
Dyspepsia (13%)
Infusion site edema (13%)
Pruritic rash (13%)
Skin disorder (13%)
Superficial injury (13%)
Frequency not defined
Angioedema
Loss of conaciousness
Seizure
Cardiac arrhythmia
Cyanosis
Warnings
Black box warnings
Anaphylactoid reactions, which may be life threatening, have been observed in some patients during idursulfase infusions
Anaphylaxis, presenting as respiratory distress, hypoxia, hypotension, urticaria and/or angioedema of throat or tongue have been reported to occur during and after infusions, regardless of duration of the course of treatment
Appropriate medical support should be readily available when idursulfase is administered
Biphasic anaphylactic reactions have also been observed after idursulfase administration, and patients who have experienced anaphylactic reactions may require prolonged observation
Patients with compromised respiratory function or acute respiratory distress may be at risk of serious acute exacerbation of their respiratory compromise due to infusion reactions and require additional monitoring
Contraindications
None listed in the manufacturer's labeL
Cautions
Risk of anaphylactoid reactions; monitor patients with compromised respiratory function/acute respiratory disease
Patients with compromised respiratory function or acute febrile or respiratory illness at the time of infusion may be at higher risk of life-threatening complications from hypersensitivity reactions
Risk of hypersensitivity and antibody development is higher in individuals with seere genetic mutations (ie, complete gene deletion, large gene rearrangement, nonsense, frameshift or splice site mutations)
Caution when administering to patients susceptible to fluid overload, or patients with acute underlying respiratory illness or compromised cardiac and/or respiratory function for whom fluid restriction is indicated; risk of serious exacerbation of cardiac or respiratory status during infusions
Development of anti-idursulfase IgG antibodies reported in 51% of patients, which may increase incidence of infusion-related reactions
A registry has been created to track adverse effects, and monitor therapeutic responses during long-term treatment; may contact 1-866-888-0660 or www.eleprase.com
Pregnancy and lactation
Pregnancy category: C
Lactation: Unknown if distributed into human breast milk, use caution
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Elaprase (idursulfase)
Mechanism of action
Replaces iduronate-2-sulfatase enzyme, which hydrolyzes the mucopolysaccharides dermatan sulfate and heparan sulfate in various cells. Respiratory, cardiac and mobility dysfunction are caused by the accumulation of these polysacharides. Physical changes and CNS involvement also occur.
Absorption
Peak plasma concentration: 1.1-1.5 mcg/mL
AUC: 169-206 min•mcg/mL
Distribution
Vd: 21-25 L
Elimination
Half-Life: 44-48 min
Clearance: 3-3.4 mL/min/kg
Administration
IV Incompatibilities
Do not infuse with other products in infusion tubing
IV Preparation
Dilute calculated volume of drug in 100 mL 0.9% NaCl; mix gently
Discard if not administered/refrigerated within 8 hr
Diluted solution may be stored in refrigerator for 48 hr
Do not use if solution is discolored
IV Administration
Infuse IV over 1-3 hr; not to exceed 8 hr
Initial infusion rate: 8 mL/hr x15 min
If well tolerated, may increase by 8 mL/hr x15 min up to 100 mL/hr
Infusion may be slowed and/or temporarily stopped or discontinued
Storage
Refrigerate vials at 2-8°C (36-46°F); protect from light
Do not freeze/shake
