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Nexviazyme Side Effects

Generic name: avalglucosidase alfa

Medically reviewed by Last updated on Aug 26, 2022.

Note: This document contains side effect information about avalglucosidase alfa. Some dosage forms listed on this page may not apply to the brand name Nexviazyme.

Applies to avalglucosidase alfa: intravenous powder for solution.


Intravenous route (Powder for Solution)

Warning: Severe hypersensitivity reactions, infusion-associated reactions, and risk of acute cardiorespiratory failure in susceptible patientsHypersensitivity Reactions including AnaphylaxisPatients treated with avalglucosidase alfa-ngpt have experienced life-threatening hypersensitivity reactions, including anaphylaxis. Appropriate medical support measures, including cardiopulmonary resuscitation equipment, should be readily available during avalglucosidase alfa-ngpt administration. If a severe hypersensitivity reaction (e.g., anaphylaxis) occurs, avalglucosidase alfa-ngpt should be discontinued immediately and appropriate medical treatment should be initiated. In patients with severe hypersensitivity reaction, a desensitization procedure to avalglucosidase alfa-ngpt may be considered.Infusion-Associated Reactions (IARs)Patients treated with avalglucosidase alfa-ngpt have experienced severe IARs. If severe IARs occur, consider immediate discontinuation of avalglucosidase alfa-ngpt, initiation of appropriate medical treatment, and the benefits and risks of readministering avalglucosidase alfa-ngpt following severe IARs. Patients with an acute underlying illness at the time of avalglucosidase alfa-ngpt infusion may be at greater risk for IARs. Patients with advanced Pompe disease may have compromised cardiac and respiratory function, which may predispose them to a higher risk of severe complications from IARs.Risk of Acute Cardiorespiratory Failure in Susceptible PatientsPatients susceptible to fluid volume overload, or those with acute underlying respiratory illness or compromised cardiac or respiratory function for whom fluid restriction is indicated may be at risk of serious exacerbation of their cardiac or respiratory status during avalglucosidase alfa-ngpt infusion. More frequent monitoring of vitals should be performed during avalglucosidase alfa-ngpt infusion in such patients.

Serious side effects of Nexviazyme

Along with its needed effects, avalglucosidase alfa (the active ingredient contained in Nexviazyme) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking avalglucosidase alfa:

More common

  • Back pain
  • bluish lips or skin
  • blurred vision
  • chest discomfort or tightness
  • chills
  • confusion
  • cough
  • diarrhea
  • difficulty swallowing
  • dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • fast, pounding, or irregular heartbeat or pulse
  • feeling of warmth
  • fever
  • general feeling of discomfort or illness
  • headache
  • hives, itching, skin rash
  • joint pain
  • loss of appetite
  • muscle aches and pains
  • nausea
  • nervousness
  • pounding in the ears
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • redness of the face, neck, arms, and occasionally, upper chest
  • runny nose
  • shakiness in the legs, arms, hands, or feet
  • shivering
  • slow or fast heartbeat
  • sore throat
  • sweating
  • trembling or shaking of the hands or feet
  • trouble breathing
  • trouble sleeping
  • unusual tiredness or weakness
  • vomiting

Other side effects of Nexviazyme

Some side effects of avalglucosidase alfa may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

  • Burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • difficulty in moving
  • swollen joints

For Healthcare Professionals

Applies to avalglucosidase alfa: intravenous injection.


The most commonly reported adverse reactions have included headache, fatigue, diarrhea, nausea, arthralgia, dizziness, myalgia, pruritus, vomiting, dyspnea, erythema, paresthesia, and urticaria.[Ref]


Very common (10% or more): Hypersensitivity reactions (48%),

Infusion associated reaction (34%)

Common (1% to 10%): Severe hypersensitivity reactions, anaphylaxis, severe infusion associate reaction

During clinical trials, life-threatening hypersensitivity reactions, including anaphylaxis, were reported. Hypersensitivity reactions occurred in 67 (48%) patients, including 6 (4%) who reported severe hypersensitivity reactions and 3 (2%) who experienced anaphylaxis. Anaphylaxis signs and symptoms included respiratory distress, chest discomfort, flushing, cough, erythema, lip swelling, pruritus, swollen tongue, dysphagia, and rash. Symptoms of severe hypersensitivity reactions included respiratory distress, erythema, urticaria, tongue edema, and rash.

The majority of infusion associated reaction (IARs) were mild to moderate. Severe IARs included symptoms of chest discomfort, nausea, dysphagia, erythema, respiratory distress, tongue edema, urticaria, and increased blood pressure.


Comparison of the incidence of antibodies in studies may be misleading due to several factors including assay methodology, sampling, etc. In studies with treatment-naive patients, the ADA at baseline was 3% and the ADA after treatment was 95%. The median time to seroconversion was 8 weeks. ADA cross-reactivity studies shown that antibodies to avalglucosidase alfa-ngpt were crossreactive to alglucosidase alfa.

Very common (10% or more): Anti-drug antibodies (up to 95%)


Very common (10% or more): Diarrhea (12%), nausea (12%)

Common (1% to 10%): Vomiting, abdominal pain


Common (1% to 10%): Myalgia, arthralgia


Common (1% to 10%): Hypertension, hypotension


Common (1% to 10%): Pruritus, erythema, urticaria, rash

Nervous system

Very common (10% or more): Headache (22%)

Common (1% to 10%): Dizziness, paresthesia


Very common (10% or more): Fatigue (18%)

Common (1% to 10%): Pyrexia, chills


Common (1% to 10%): Dyspnea, cough


1. "Product Information. Nexviazyme (avalglucosidase alfa)." Genzyme Corporation (2021):

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.