Laronidase
Laronidase is an enzyme replacement therapy used to treat Mucopolysaccharidosis I (MPS I), a rare inherited metabolic disorder, in adults and children.
🧬 Where this information comes from Click to expand
The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 1 clinical label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →
⚠️ FDA Boxed Warning — the FDA’s strongest safety alert ▾
Aldurazyme carries a boxed warning — the FDA's most serious warning — about life-threatening allergic reactions and serious breathing complications. Some patients have experienced anaphylaxis (a severe whole-body allergic reaction) and other dangerous hypersensitivity reactions during or shortly after the infusion. Emergency medical equipment, including resuscitation gear, must be immediately available every time this medication is given. If a severe reaction occurs, the infusion must be stopped immediately and emergency treatment started. Patients who already have breathing difficulties or an active respiratory illness are at particular risk for dangerous breathing problems during infusion and require extra monitoring and respiratory support.
📖 Laronidase: Patient Information Guide
A plain-language walkthrough of Laronidase — what it treats, how it works, how it’s taken, side effects, warnings and interactions. Tap any section to expand it.
🎯What it's used for▾
Laronidase is an enzyme replacement therapy approved for Mucopolysaccharidosis I (MPS I), a rare inherited disease in which the body cannot properly break down certain complex sugars. Aldurazyme (the IV injection form) is approved for:
- Adults and children with the Hurler form of MPS I
- Adults and children with the Hurler-Scheie form of MPS I
- Patients with the Scheie form of MPS I who have moderate to severe symptoms
Aldurazyme has not been shown effective for mildly affected patients with the Scheie form, and it has not been evaluated for effects on brain or central nervous system (CNS) symptoms of MPS I.
⚙️How it works▾
MPS I is caused by a shortage of an enzyme called alpha-L-iduronidase. This enzyme normally breaks down glycosaminoglycans (GAGs) — long sugar-chain molecules — inside cell compartments called lysosomes. Without enough of the enzyme, GAGs accumulate throughout the body, gradually damaging cells, tissues, and organs. Laronidase is a lab-made (recombinant) version of this missing enzyme. When infused intravenously, it is taken up into cells through special receptor sites and works inside the lysosomes to break down the accumulated GAGs, reducing their harmful buildup.
Because the blood-brain barrier limits which proteins can enter the brain, intravenously given laronidase cannot be assumed to reach or affect the central nervous system. Its ability to cross the blood-brain barrier has not been evaluated.
💊How it's taken▾
Aldurazyme is given as a once-weekly intravenous (IV) infusion in a clinical setting, typically over about 3 to 4 hours. The infusion starts slowly and the rate is gradually increased as tolerated. Patients are usually pre-medicated with antihistamines — with or without antipyretics (fever reducers) — about 60 minutes before the infusion starts.
- Infusions must be administered by a healthcare professional with emergency equipment on hand
- If a dose is missed, restart as soon as possible and maintain the weekly schedule — do not double up on doses
- Patients with heart or breathing problems may receive a smaller infusion volume at a slower rate
🤒Side effects — in detail▾
The most common side effects with Aldurazyme are infusion-related reactions, which tend to become less frequent over time and are usually mild to moderate:
- Fever and chills
- Flushing (skin warmth or redness)
- Rash
- Increased blood pressure or fast heartbeat
- Decreased oxygen levels during infusion
- Headache
- Upper respiratory tract infection
- Injection site reactions or pain
Serious reactions including anaphylaxis (severe allergic reaction), acute breathing problems, and cardiorespiratory failure have been reported and require immediate medical attention. Infusion should be stopped immediately if a severe reaction occurs.
⚠️Warnings & precautions▾
- Severe allergic reactions (anaphylaxis): Life-threatening allergic reactions can occur during or up to 3 hours after infusion. Emergency medical equipment must always be available. Signs include difficulty breathing, throat tightening, hives, and low blood pressure.
- Breathing complications: Patients with existing breathing problems, sleep apnea, or acute respiratory illness face higher risk for serious respiratory events during infusion. Airway status should be assessed before starting treatment, and respiratory support must be on hand.
- Acute cardiorespiratory failure: Post-marketing reports have documented acute heart and breathing failure in MPS I patients with underlying disease during infusions. Patients prone to fluid overload need careful monitoring and may need a reduced infusion volume and rate.
- Infusion-associated reactions (IARs): Milder infusion reactions are common. Pre-medication and having emergency support available are standard precautions. If a severe IAR occurs, the infusion must be stopped and treated immediately.
- Immunogenicity (antibody formation): Most patients develop antibodies against laronidase. In some cases, these antibodies can affect how quickly the drug is cleared or reduce its effectiveness.
🔀What it interacts with▾
The Aldurazyme label does not identify specific drug, food, or supplement interactions. However, there are important clinical considerations during infusion:
- Other IV products: Aldurazyme should not be infused through the same IV line as other medications
- Epinephrine (adrenaline): Use with caution in MPS I patients who may need it for allergic reactions, due to an increased prevalence of coronary artery disease in this population
- Antihistamines and antipyretics: These are routinely given before each infusion to reduce the risk of reactions; antihistamines may cause drowsiness, so supplemental oxygen or CPAP should be available for patients who use them at night
This is not a complete list of interactions. Always talk with your doctor or pharmacist before starting, stopping, or changing any medication.
📋Before taking it▾
- Breathing problems or sleep apnea: Tell your doctor — airway patency should be evaluated before starting Aldurazyme, and respiratory support must be available during infusions
- Heart disease or fluid retention: Patients susceptible to fluid overload may need a reduced infusion volume and slower rate, plus extra monitoring
- Active fever or respiratory illness: Infusion may need to be delayed if you are acutely unwell on infusion day
- Pregnancy: Available data from over 30 pregnant women have not shown a clear drug-related risk of birth defects or miscarriage, but untreated MPS I itself can worsen during pregnancy. Continue or stop treatment based on an individualized discussion with your doctor
- Breastfeeding: It is not known whether laronidase passes into breast milk. Discuss the risks and benefits with your doctor
- Children: Aldurazyme is approved for children as young as 6 months of age with Hurler and Hurler-Scheie forms; safety and effectiveness were found to be similar across pediatric age groups
- Older adults (65+): Clinical studies did not include patients aged 65 and older, so it is unknown whether they respond differently
- Antibody development: Most patients develop antibodies to laronidase; your care team may monitor this as it can affect how your body processes the drug
📡Pharmacodynamics — effects in the body▾
The pharmacodynamic effect of Aldurazyme is measured by reductions in urinary glycosaminoglycan (GAG) levels — a marker of how well the enzyme is breaking down accumulated GAGs in the body. How urinary GAG levels respond to changes in Aldurazyme dose is not yet fully understood, and the relationship between urinary GAG levels and broader clinical outcomes has also not been definitively established.
🔬Pharmacokinetics — how your body processes it▾
After a 4-hour intravenous infusion in patients 6 years and older, laronidase reaches its peak blood concentration during the infusion and is cleared relatively quickly, with an elimination half-life (the time it takes for half the drug to leave the body) of about 1.5 to 3.6 hours. In younger children (6 months to 5 years), the half-life ranged from about 0.3 to 1.9 hours, reflecting somewhat faster clearance. The drug distributes into body tissues and is cleared through the plasma. In patients who develop antibodies (ADA) against laronidase, clearance can be faster — particularly in the earlier weeks of treatment — though clearance tends to normalize over time.
📦How to store it▾
Refrigerate vials of ALDURAZYME at 2°C to 8°C (36°F to 46°F). Do not freeze or shake. Protect from light.
📄 Written from Laronidase’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Every point is grounded in that labeling — nothing is invented. How we use AI →
🩺 Pharmacist Counseling Corner
Quick, plain-English answers to the questions patients ask most about Laronidase — the kind of thing our pharmacy team would talk through with you at the counter.
What exactly is Aldurazyme doing for my MPS I? ▾
Why does the infusion take so long, and what happens if I react to it? ▾
Will Aldurazyme help with my brain or cognitive symptoms? ▾
What should I do if I miss a weekly infusion? ▾
I'm pregnant — is it safe to keep taking Aldurazyme? ▾
My child is only a toddler — is Aldurazyme safe for young children? ▾
Is Laronidase available over the counter? ▾
When was Laronidase first available? ▾
Who makes Laronidase? ▾
💬 Answers drafted from Laronidase’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Grounded in that labeling — nothing is made up. How we use AI →
🧰 Keep exploring
💊 How Laronidase comes
Laronidase is available in 1 form. Different forms and brands can have different approved uses, doses, schedules, and directions. Follow the instructions for your exact product, and do not switch forms without guidance from your prescriber or pharmacist.
Injection
How this form is used
- Aldurazyme is used to treat adults and children with the Hurler and Hurler-Scheie forms of MPS I
- Aldurazyme is used for patients with the Scheie form of MPS I who have moderate to severe symptoms
- Aldurazyme has not been shown effective for mildly affected Scheie form patients or for CNS symptoms of MPS I
- Aldurazyme is diluted in 0.9% Sodium Chloride and given as a slow intravenous infusion, typically over 3 to 4 hours, once weekly
- Aldurazyme must be administered through a low-protein-binding, 0.2-micron in-line filter using an infusion set; it should not be mixed with other IV products in the same line
- Before each Aldurazyme infusion, antihistamines — with or without fever-reducing medication — are recommended about 60 minutes in advance to help reduce infusion reactions
- If an Aldurazyme infusion is missed, restart as soon as possible and maintain the one-week schedule; do not give a double dose to make up for the missed one
📊 Laronidase across the U.S. market
How Laronidase appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.
Share of FDA-listed product records by manufacturer — FDA National Drug Code Directory. Record counts are not sales or prescription volume.
📈 How widely Laronidase is used
A general measure of how commonly Laronidase is prescribed, based on Medicaid — one of the largest public drug programs. The figure below is prescriptions filled in Q1–Q4 2025, summed across every form and brand of the drug.
Think of this as a proxy for how widely Laronidase is used, drawn from freely available public data. Medicaid is just one program — these numbers don’t include Medicare, other government coverage, or commercial and cash-pay prescriptions, so real-world use is higher than what’s shown here.
How commonly is Laronidase prescribed? Of the 1,594 medications we measure, Laronidase ranks #1,364 by Medicaid prescriptions — more than 14% of them.
Utilization by Laronidase product
Pick a product to see its own Medicaid numbers. Each chip is one clinical product — a specific strength & dosage form as defined by RxNorm — with brand-name and generic versions combined.
5 ML laronidase 0.58 MG/ML Injection
Summed across the 1 of 1 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 403822
Shares are of the Medicaid prescriptions shown here. Product grouping follows RxNorm (the National Library of Medicine’s drug terminology), so “one product” means one strength & dosage form regardless of manufacturer. Dollar figures are gross Medicaid reimbursement before mandatory rebates — rebates (often large, especially for brand-name drugs) are confidential, so actual net cost to Medicaid is lower than shown.
Source: Medicaid State Drug Utilization Data (CMS), aggregated by generic ingredient — summed across every NDC (all brands, strengths, salt forms and dosage forms) of Laronidase, and across all states and both fee-for-service and managed-care claims. A general popularity signal; it excludes Medicare, commercial insurance and cash prescriptions, so it is not total U.S. use. Based on the 1 of 1 listed Laronidase NDCs with Medicaid activity.
🔍 Compare Laronidase products
A representative set of FDA-listed product records for Laronidase — across manufacturers, strengths, and dosage forms, grouped by form with each product’s manufacturer and how the FDA approved it. The same medicine may be made and packaged by different companies, so a single drug can have many directory entries. (It’s also why a refill can look different — a new shape, color, or box — even though it contains the same medication.)
| Strength | Route | Manufacturer / Labeler | Category ⓘ | Details |
|---|---|---|---|---|
| 💊Injection | ||||
| 2.9 mg/5 mL | — | BioMarin Pharmaceutical Inc. | DRUG FOR FURTHER PROCESSING | View NDC → |
| 2.9 mg/5 mL | Intravenous | Genzyme Corporation × 5 listings | BLA | View NDC → |
Showing 6 of 6 products — FDA National Drug Code Directory. See every product, package size and price: browse all 6 Laronidase NDCs →
📈 What people report — real-world data (FDA FAERS)
After a medicine reaches the market, patients, doctors and drugmakers can send the FDA reports of problems they think may be linked to it. Here’s what’s been reported for Laronidase — a signal of what to watch for, not proof the drug caused it.
Source: openFDA, from the FDA Adverse Event Reporting System (FAERS). These are voluntary reports — they don’t prove the drug caused the effect, and counts reflect how often something was reported, not how often it actually happens. Reports also often name the very problem the medicine is taken for — a common reason to file one is that the drug didn’t help — so for a pain reliever you may see “pain” high on the list; that points to why the report was filed, not to the drug causing the symptom. This counts every report that lists Laronidase in any role, so the total runs higher than the FDA’s official dashboard, which counts only cases where the drug is the suspect. For the authoritative figures, see the FDA FAERS Public Dashboard. Always talk to your pharmacist or doctor.
🏛️ The road to your pharmacy
How Laronidase went from FDA review to the pharmacy shelf — the key milestones in its regulatory journey.
Source: Drugs@FDA.
🚨 Recall history
A recall is when a specific batch of a medicine is pulled from the market — usually a manufacturing issue, not a problem with the drug itself. Class I is most serious, Class III least.
Source: openFDA drug enforcement (recall) reports.
RxNorm Concept Web — From Ingredient to Every Form and Strength
This page starts with one ingredient concept (IN). The branches below show its dose-form concepts (SCDF), then the available clinical drug and strength concepts (SCD). Combination products remain separate concepts with their own pages.
RxCUI 392509 1 dose form · 1 strength
-
Dose form (SCDF) Injection RxCUI 1860090In current FDA listingsClinical drug / strength (SCD) 5 ML laronidase 0.58 MG/MLRxCUI 403822
Look up RxCUI 392509 in the RxCUI Atlas →
RxNorm is the U.S. National Library of Medicine’s normalized drug vocabulary. Its concept hierarchy can include forms that are not currently marketed; the status on each branch compares that concept with current FDA listings. RxCUIs identify vocabulary concepts, not individual packages or manufacturers.
📦 Supply & shortage status
Whether Laronidase is in short supply in the U.S. right now, plus any shortage history the FDA has on record. A shortage usually reflects a manufacturing or demand issue — not a safety problem with the drug.
Source: openFDA, from the FDA Drug Shortages database.
🏷️ Sold under these brand names
🏭 Manufacturers & labelers
RxNorm drug class
Laronidase belongs to the Hydrolytic Lysosomal Glycosaminoglycan-specific Enzyme class.
Classified by RxNorm RxClass — the U.S. National Library of Medicine's standardized drug-classification service (Established Pharmacologic Class from the FDA, the ATC drug family from the WHO, and mechanism of action). Reference only, not medical advice.
🔬 Where this comes from
Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.
How we combine label and product data
HelloPharmacist combines public FDA and NLM records; we don’t author the underlying clinical facts. We identified 1 FDA-filed SPL label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. The representative label is the starting point for the displayed reference monograph; the 12 largest stored in-scope SPL records, which may include that representative, are compared section by section, and the longest available version of each section is retained. Forms, routes, brands, labelers, product-listed strengths, and product-record counts are aggregated separately from ingredient-matched FDA NDC Directory records; package records listed above are associated with the linked SPL; and the normalized concept hierarchy comes from NLM RxNorm.
For canonical ingredient pages, bounded product-attributed indication and administration excerpts may be added to the AI evidence, and the generator is instructed to preserve available product, brand, route, and form qualifiers instead of treating one label as universal. Where a section is identified as AI-written, its plain-language text is generated from bounded label evidence. New draft drug pages remain in the admin review queue before first publication. Genzyme Corporation is the representative DailyMed label linked for verification and dates; it is not the sole source used for the page.
This is general education, not medical advice — always consult your doctor or pharmacist about your medications and any medical condition. For the exact wording of the linked representative label, view that label on DailyMed; some displayed composite sections may come from other in-scope SPL labels. Learn how we use AI and our data sources & update cadence.