vestronidase alfa

General

Pronunciation:
ves-tron-i-dase al-fa

Trade Name(s)

Mepsevii

Ther. Class.

replacement enzyme

Pharm. Class.

enzymes

Indications

Mucopolysaccharidosis VII.

Action

Recombinant form of human beta-glucuronidase, which is taken up by lysosomes and causing catabolism of accumulated glycosaminoglycans in affected tissues.

Therapeutic Effect(s):

Improved motor and pulmonary function and reduced liver and spleen volumes.

Pharmacokinetics

Absorption: IV administration results in complete bioavailability.

Distribution: Well distributed to tissues.

Metabolism and Excretion: Eliminated by proteolytic degradation into small peptides and amino acids.

Half-life: 2.6 hr

TIME/ACTION PROFILE (plasma concentrations)

ROUTE	ONSET	PEAK	DURATION
IV	unknown	unknown	unknown

Contraindication/Precautions

Contraindicated in:

None.

Use Cautiously in:

OB: Safety not established in pregnancy;
Lactation: Use while breastfeeding only if potential maternal benefit justifies potential risk to infant.

Adverse Reactions/Side Effects

CV: peripheral edema

Derm: pruritus, rash

GI: diarrhea

Local: extravasation, infusion site reactions

Misc: ANAPHYLAXIS

* CAPITALS indicate life-threatening.
Underline indicate most frequent.

Interactions

Drug-Drug

None reported.

Route/Dosage

IV (Adults and Children): 4 mg/kg every 2 wk.

Availability

Solution for injection: 2 mg/mL

Assessment

Assess for signs and symptoms of infusion reaction (respiratory distress, cyanosis, decreased oxygen saturation, hypotension) during and for at least 60 min after completion of infusion. Discontinue infusion immediately if signs and symptoms of anaphylaxis occur.
Obtain patient weigh prior to infusion to determine dose.

Implementation

IV Administration

Administer a nonsedating antihistamine 30–60 min prior to start of infusion.
Intermittent Infusion: Allow vials to reach room temperature before diluting; do not heat, microwave, or shake. Solution is clear and colorless to slightly yellow; may have thin translucent fibers. Do not administer solutions that are discolored or contain particulate matter. Use an 18-gauge needle to slowly remove dose from vials to avoid agitation, turbulence, or bubbles. Slowly add solution to empty infusion bag. Add 0.9% NaCl equal to volume of medication. Gently rock bag to mix; do not shake.
Rate: Infuse via in-line, low-protein binding 0.2-micron filter over 4 hr. Infuse first 2.5% of total volume over first hr. Account for dead space in lines to ensure 2.5% of total infusion volume is delivered into patient's bloodstream during 1st hr of infusion. Then increase infusion rate as tolerated to complete infusion over following 3 hr. Do not flush line to prevent rapid bolus of medication. May add 0.9% NaCl through Y-site or piggyback to maintain flow and prevent clotting or line blockage. Complete infusion within 42 hr of dilution. Solution is stable for 6 hr at room temperature or 36 hr if refrigerated.
Y-Site Incompatibility: Do not administer other products through infusion tubing.

Patient/Family Teaching

Explain purpose of medication to patient.
Instruct patient to notify health care professional immediately if signs and symptoms of anaphylaxis (rash, pruritus, hives, swelling of face and neck, dyspnea, fainting, dizziness, feeling light-headed) occur.
Rep: Advise females of reproductive potential to notify health care professional if pregnancy is planned or suspected or if breastfeeding.

Evaluation/Desired Outcomes