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- Source: Campus Sanofi
Weight-Based Dosing Calculator for Mucopolysaccharidosis I Therapy
This calculator supports healthcare professionals in determining weight-based dosing for enzyme replacement therapy used in Mucopolysaccharidosis I, a rare lysosomal storage disorder. Accurate dosing is important given the chronic, weekly infusion schedule typically required in this condition. The tool is intended as a calculation aid alongside full prescribing information and institutional infusion protocols.
As your patients with MPS I grow, so should their Aldurazyme® treatment1
Calculating the recommended dose of Aldurazyme® for children and adults with MPS I
Recommended dosing regimen:
• 100 U/kg of body weight administered once a week*1
• No dose adjustment is required for pediatric patients1
How to calculate dose:
To calculate the recommended dose of Aldurazyme® in U and mg per week, and the corresponding number of vials required, enter the patient’s body weight (1–120 kg) in the box.
Enter body weight (kg) below
Patient dose (U)
Patient dose (mg)
Vials per week (n)
Please refer to the Summary of Product Characteristics for full information on the use of Aldurazyme® for the treatment of MPS I.
* The activity unit (U) is defined as the hydrolysis of one micromole of substrate (4-MUI) per minute.1
Administration
Administering the Aldurazyme® infusion
Recommended Aldurazyme® infusion rate and speed:
The initial infusion rate of 2 U/kg/h may be incrementally increased every fifteen minutes, if tolerated, to a maximum of 43 U/kg/h.1
If body weight ≤20 kg1
Total infusion volume of 100 ml to be delivered in approximately 3–4 hours.
| Infusion rate (U/kg/h) | Infusion speed (ml/h) |
| 2 | 2 |
| 4 | 4 |
| 8 | 8 |
| 16 | 16 |
| 32 | 32 |
| 43 | 43 |
If body weight >20 kg1
Total infusion volume of 250 ml to be delivered in approximately 3–4 hours.
| Infusion rate (U/kg/h) | Infusion speed (ml/h) |
| 2 | 5 |
| 4 | 10 |
| 8 | 20 |
| 16 | 40 |
| 32 | 80 |
| 43 | ≈107 |
For the initial administration of Aldurazyme® or upon re-administration following interruption of treatment, it is recommended that patients be administered pre-treatment medicines (antihistamines and/or antipyretics) approximately 60 minutes prior to the start of the infusion, to minimize the potential occurrence of infusion-associated reactions.1
If clinically indicated, administration of pre-treatment medications with subsequent infusions of Aldurazyme® should be considered.1
Aldurazyme® treatment should be supervised by a physician experienced in the management of patients with MPS I or other inherited metabolic diseases. Administration of Aldurazyme® should be carried out in an appropriate clinical setting where resuscitation equipment to manage medical emergencies would be readily available.1
Support optimal ALDURAZYME® treatment by regularly monitoring your patient’s weight and adjusting their dose as required. Always ensure to administer the indicated and appropriate ALDURAZYME® dose.
IAR: Infusion associated reactions; MPS I: Mucopolysaccharidosis 1.
Safety
Safety information
Infusion associated reactions (IAR)
IARs, defined as any related adverse event occurring during the infusion or until the end of the infusion day have been reported in patients treated with ALDURAZYME®.1
Severe IARs have been reported in patients with pre-existent severe underlying upper airway involvement.1 These patients should be closely monitored and only be infused in an appropriate clinical setting where resuscitation equipment is available.1
Hypersensitivity reactions, including anaphylaxis, have been reported with ALDURAZYME®.1
Some of these reactions were life- threatening and included respiratory failure/distress, stridor, obstructive airways disorder, hypoxia, hypotension, bradycardia and urticaria. If severe hypersensitivity reactions occur, the infusion of ALDURAZYME® should be discontinued immediately.1
In case of a:1
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Mild or moderate IAR, treatment with antihistamines and paracetamol/ibuprofen should be considered and/or a reduction in the infusion rate to half the infusion rate at which the reaction occurred. |
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Single severe IAR, the infusion should be stopped until the symptoms are resolved and treatment with antihistamines and paracetamol/ ibuprofen should be considered. The infusion can be restarted with a reduction of the infusion rate to 1/2 – 1/4 the rate of the infusion at which the reaction occurred. |
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Recurrent moderate IAR or re-challenge after a single severe IAR, pre-treatment should be considered (antihistamines and paracetamol/ ibuprofen and/or corticosteroids) and a reduction of the infusion rate to 1/2 – 1/4 the rate of the infusion at which the previous reaction occurred. |
Most frequent adverse drug reactions (ADRs)
The most frequent ADRs in clinical trials were: headache, nausea, abdominal pain, rash, arthralgia, backpain, pain at extremity, flushing, pyrexia, infusion site reactions, blood pressure increased, oxygen saturation decreased, tachycardia and chills.1
Post-marketing experience of infusion-associated reactions revealed reporting of cyanosis, hypoxia, tachypnea, pyrexia, vomiting, chills and erythema, in which some of these reactions were severe.1
ADR: adverse drug reactions; IAR: infusion associated reactions; MPS I: mucopolysaccharidosis I.
ALDURAZYME® abbreviated prescribing information
Aldurazyme® 100 U/ml concentrate for solution for infusion laronidase
What Aldurazyme® is and what it is used for:
Aldurazyme® is used to treat patients with MPS I disease (Mucopolysaccharidosis 1). It is given to treat the non-neurological manifestations of the disease.People with MPS I disease have either a low level or no level of an enzyme called α-L-iduronidase, which breaks down specific substances (glycosaminoglycans) in the body. As a result, these substances do not get broken down and processed by the body as they should. They accumulate in many tissues in the body, which causes the symptoms of MPS I. Aldurazyme is an artificial enzyme called laronidase. This can replace the natural enzyme which is lacking in MPS I disease.
What you need to know before you are given Aldurazyme®
CONTRAINDICATIONS
You should not be given Aldurazyme®
If you are allergic (hypersensitive) to laronidase or any of the other ingredients of this medicine.
WARNINGS AND PRECAUTIONS
Talk to your doctor before using Aldurazyme®.
Contact your doctor immediately if treatment with Aldurazyme® causes:
- Allergic reactions, including anaphylaxis (a severe allergy reaction). Some of these reactions may be life-threatening. Symptoms may include respiratory failure/distress (inability of lungs to work properly), stridor (high-pitched breathing sound) and other disorders due to obstruction of airways, rapid breathing, excessive contraction of the airway muscles causing breathing difficulty (bronchospasm), lack of oxygen in body tissues (hypoxia), low blood pressure, slow heart rate, or itchy rash (urticaria).
- Infusion-associated reactions i.e. any side effect occurring during the infusion or until the end of the infusion day.
If these reactions occur, the Aldurazyme® infusion should be stopped immediately and appropriate treatment will be started by your doctor.
These reactions may be particularly severe if you have a pre-existing MPS I-related upper airway obstruction.
You may be given additional medications to help prevent allergic-type reactions, such as antihistamines, medicine to reduce fever (e.g. paracetamol) and/or corticosteroids.
Your doctor will also decide if you can continue receiving Aldurazyme®.
PREGNANCY, BREAST-FEEDING AND FERTILITY
There is not enough experience of the use of Aldurazyme® in pregnant women. You should not be given Aldurazyme® during pregnancy unless clearly necessary.
It is not known whether Aldurazyme® appears in breast milk. It is recommended to stop breast-feeding during treatment with Aldurazyme®.
No information is available on the effects of Aldurazyme® on fertility.
If you are pregnant or breast-feeding, think you may be pregnant or are planning to have a baby, ask your doctor or pharmacist for advice before using this medicine.
DRIVING AND USING MACHINES
The effects on the ability to drive and to use machines have not been studied.
POSSIBLE SIDE EFFECTS
Like all medicines, this medicine can cause side effects, although not everybody gets them.
Side effects were mainly seen while patients were being given the medicine or shortly after (infusion-associated reactions). If you experience any reaction like this, you should contact your doctor immediately. The number of these reactions decreased the longer that patients were on Aldurazyme®.
The majority of these reactions were mild or moderate in intensity. However, severe systemic allergic reaction (anaphylactic reaction) has been observed in patients during or up to 3 hours after Aldurazyme® infusions. Some of the symptoms of such a severe allergic reaction were life-threatening and included extreme difficulty breathing, swelling of the throat, low blood pressure, and low oxygen level in the body. A few patients who had a prior history of severe MPS I related upper airway and pulmonary involvement, experienced severe reactions including bronchospasm (airway constriction), respiratory arrest, and swelling of the face. The frequency of bronchospasm and respiratory arrest is unknown. The frequency of severe allergic reaction (anaphylactic reaction) and swelling of the face is considered common and may affect up to 1 in 10 people.
Very common symptoms (may affect more than 1 in 10 people): Which were not serious include headache, nausea, abdominal pain, rash, joint disease, joint pain, back pain, pain in arms or legs, flushing, fever, chills, increased heart rate, increased blood pressure and reaction at the infusion site, such as swelling, redness, build-up of fluid, discomfort, itchy rash, pale colour of the skin, discoloured skin, or sensation of being warm.
Common (may affect up to 1 in 10 people):
Increased body temperature, tingling, dizziness, cough, difficulty in breathing, vomiting, diarrhoea, rapid swelling under the skin in areas such as the face, throat, arms and legs which can be life-threatening if throat swelling blocks the airway, hives, itching, hair loss, cold sweat, heavy sweating, muscle pain, paleness, cold hands or feet, feeling hot, feeling cold, fatigue, influenza like illness, pain at injection site, restlessness.
Always read the full prescribing information.
Healthcare professionals are asked to report any suspected adverse reactions to Egyptian pharmacovigilance center (EPVC).
- E-mail: pv.followup@edaegypt.gov.eg or Egyptian Drug Authority (EDA) Website: https://www.edaegypt.gov.eg.
-
Hotline: 15301.
Aldurazyme Egyptian Drug Authority (EDA) leaflet approval date: 16.7.2024.
Approval Code (No.) BF0065OA4089/062025 Invalidation Date 20/04/2027
- Aldurazyme Egyptian Drug Authority (EDA) leaflet approval date: 16.7.2024.
Dosing for enzyme replacement therapy in Mucopolysaccharidosis I is calculated based on the patient's body weight and is typically administered as a weekly intravenous infusion. The infusion rate is usually increased gradually during early treatment cycles to monitor tolerability. Healthcare professionals should confirm the specific regimen against current prescribing information for this rare disease indication.
Patients require monitoring for infusion-associated reactions, which are more common during early treatment cycles and typically managed with pre-medication and controlled infusion rates. Vital signs are usually monitored throughout the infusion, particularly during initial doses. Long-term monitoring also includes tracking disease-specific clinical markers relevant to Mucopolysaccharidosis I.
Mucopolysaccharidosis I is a progressive condition, and starting enzyme replacement therapy earlier in the disease course is associated with better preservation of organ function and quality of life. Delayed diagnosis can allow irreversible skeletal, cardiac or respiratory complications to develop. Healthcare professionals should maintain a high index of suspicion in patients presenting with characteristic multisystem features.
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