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Asparaginase Erwinia Chrysanthemi Injection

Asparaginase erwinia chrysanthemi injection (Rylaze) is an enzyme-based cancer medicine used with other chemotherapy to treat acute lymphoblastic leukemia and lymphoblastic lymphoma in people who became allergic to E. coli-derived asparaginase.

Brand names ErwinazeRylaze
Drug class Asparagine-specific Enzyme
Rx Form 1
Dr. Brian Staiger, PharmD, BCPS
Reviewed by Last reviewed Jul 10, 2026 Content updated Oct 2, 2026
🧬 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 →

✓No current FDA shortage listed · checked Oct 6, 2026
Asparaginase Erwinia Chrysanthemi Injection at a glance The quick version — the full detail is in the Patient Information Guide below.
Dr. Brian Staiger, PharmD, BCPS
The Pharmacist’s Take By · Clinical pharmacist · Written

Rylaze is a specialist enzyme, on the U.S. market since about 2021, that breaks down asparagine, an amino acid some leukemia cells must take from the blood; it is used with other chemotherapy for acute lymphoblastic leukemia and lymphoblastic lymphoma once someone becomes allergic to E. coli-derived asparaginase. Expect a demanding course, with tiredness, nausea, muscle and joint aches and bruising most noticeable. The main risk is a serious allergic reaction (face swelling, hives, wheezing), so it is given after preventive medicines where anaphylaxis can be treated. Severe stomach pain, sudden bad headache or yellowing eyes mean calling the care team right away, since it can cause pancreatitis, clots, bleeding and liver damage.

Clinical pearls

  • Doses run every 48 hours or Monday, Wednesday and Friday, so a missed clinic visit leaves a gap; reschedule it promptly.
  • Hormonal birth control is not the advised method; use effective non-hormonal contraception during treatment and for 3 months after the last dose.
  • Hold off on breastfeeding during treatment and for 1 week after the final dose.
  • Report quick weight gain or a swelling belly, which can signal hepatic veno-occlusive disease, a blockage of small veins in the liver.
How you get itPrescription only
Comes asInjection
Earliest FDA record2021
Companies listing it with the FDA1
FDA label last updatedJul 1, 2025
FDA’s strongest warning (boxed)None on the label

Patient information guide A plain-language walkthrough of Asparaginase Erwinia Chrysanthemi Injection, written from its FDA label.

What Asparaginase Erwinia Chrysanthemi Injection is used for

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Rylaze is an asparaginase enzyme used as part of combination chemotherapy.

  • Acute lymphoblastic leukemia (ALL)
  • Lymphoblastic lymphoma (LBL)
  • For adults and children 1 month or older who developed hypersensitivity to E. coli-derived asparaginase

How Asparaginase Erwinia Chrysanthemi Injection works

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Rylaze is an enzyme that converts the amino acid L-asparagine into aspartic acid and ammonia. This lowers asparagine levels in the blood.

Leukemia cells with low asparagine synthetase cannot make their own asparagine. They rely on the blood supply, so depleting it kills them.

Asparaginase Erwinia Chrysanthemi Injection dosage

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Rylaze is an intramuscular injection given by a healthcare professional. It replaces a long-acting asparaginase product, using one of two schedules.

  • One schedule is every 48 hours.
  • The other is Monday, Wednesday and Friday, with the Friday dose given in the afternoon.
  • Premedicines are given 30 to 60 minutes before each dose.
  • Blood tests for liver function and glucose are checked regularly.

Ask your care team what to do about a missed dose.

Dosing details from the FDA-approved label

From the Asparaginase Erwinia Chrysanthemi Injection prescribing information (“Dosage and Administration”). Doses are set by your prescriber for your product, condition, kidney function and age — never change a dose on your own.

  • Replacement of a long-acting asparaginase product - every 48 hours regimen
    • 25 mg/m2 intramuscularly every 48 hours
    • Replace one dose of calaspargase pegol products with 11 doses of RYLAZE, or one dose of pegaspargase products with 7 doses of RYLAZE
    • Premedicate with acetaminophen, an H-1 receptor blocker and an H-2 receptor blocker 30-60 minutes prior to administration
  • Replacement of a long-acting asparaginase product - Monday/Wednesday/Friday regimen
    • 25 mg/m2 intramuscularly on Monday morning and Wednesday morning, and 50 mg/m2 intramuscularly on Friday afternoon
    • Replace one dose of calaspargase pegol products with 9 doses of RYLAZE, or one dose of pegaspargase products with 6 doses of RYLAZE
    • Administer the Friday afternoon dose 53 to 58 hours after the Wednesday morning dose
Read the label’s full dosing text

2 DOSAGE AND ADMINISTRATION There are two RYLAZE regimens that can be used to replace a long-acting asparaginase product. The recommended dosages of RYLAZE are: When administered every 48 hours • 25 mg/m 2 intramuscularly every 48 hours; When administered Monday/Wednesday/Friday • 25 mg/m 2 intramuscularly on Monday morning and Wednesday morning and 50 mg/m 2 intramuscularly on Friday afternoon. ( 2.1 ) 2.1 Recommended Dosage There are two RYLAZE regimens that can be used to replace a long-acting asparaginase product. The recommended dosages of RYLAZE are: When administered every 48 hours: • 25 mg/m 2 administered intramuscularly every 48 hours; When administered on a Monday/Wednesday/Friday schedule: • 25 mg/m 2 intramuscularly on Monday morning and Wednesday morning, and 50 mg/m 2 intramuscularly on Friday afternoon. Administer the Friday afternoon dose 53 to 58 hours after the Wednesday morning dose (e.g., 8:00 am on Monday and Wednesday, and 1:00 pm to 6:00 pm on Friday) [see Clinical Pharmacology ( 12.3 ), Clinical Studies ( 14 )] . Table 1 shows the number of RYLAZE dosages recommended for the intended duration of treatment for replacement of one dose of calaspargase pegol products (3 weeks of asparaginase coverage) or one dose of pegaspargase products (2 weeks of asparaginase coverage). See the full prescribing information for the long-acting asparaginase product to determine the total duration of administration of RYLAZE as replacement therapy. Table 1: Recommended Duration of RYLAZE Dosing to Replace One Long-Acting Asparaginase Dose When RYLAZE is Administered: Recommended Duration of RYLAZE to Replace Calaspargase Pegol Products Recommended Duration of RYLAZE to Replace Pegaspargase Products 25 mg/m 2 intramuscular every 48 hours Replace one dose of calaspargase pegol products with 11 doses of RYLAZE Replace one dose of pegaspargase products with 7 doses of RYLAZE 25 mg/m 2 intramuscular on Monday morning and Wednesday morning, and 50 mg/m 2 intramuscular on Friday afternoon* Replace one dose of calaspargase pegol products with 9 doses of RYLAZE Replace one dose of pegaspargase products with 6 doses of RYLAZE *See bullet above for timing of 25/25/50 mg/m 2 dosing of RYLAZE.

Excerpted — the section continues on the label. Read the full Dosage and Administration section on DailyMed →

Asparaginase Erwinia Chrysanthemi Injection side effects

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Common side effects seen with Rylaze plus chemotherapy include:

Common side effects

  • Abnormal liver tests
  • Nausea and vomiting
  • Muscle and joint pain
  • Infections
  • Tiredness
  • Headache
  • Fever, including febrile neutropenia (fever with low white blood cells)
  • Bleeding or bruising
  • Mouth sores, belly pain, diarrhea and decreased appetite
  • High blood sugar and low potassium

When to get medical help

  • Signs of a serious allergic reaction, such as swelling of the lips, eyes or face, hives, trouble breathing, wheezing or low blood pressure
  • Severe stomach pain, which may signal pancreatitis (inflammation of the pancreas)
  • Signs of a blood clot, such as sudden severe headache or shortness of breath
  • Serious or ongoing bleeding
  • Signs of liver problems, including hepatic veno-occlusive disease: rapid weight gain, fluid buildup in the belly, a painful enlarged liver, or yellowing of the skin or eyes
  • Fever or other signs of infection

Asparaginase Erwinia Chrysanthemi Injection warnings and precautions

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  • Allergic reactions: reported in 29% of patients in trials, severe in 6%. Anaphylaxis occurred in 2%.
  • Pancreatitis: reported in 20% of patients, severe in 8%.
  • Blood clots: serious clots occurred in 1%.
  • Bleeding: reported in 25%, severe in 2%.
  • Liver toxicity: elevated bilirubin or transaminases occurred in 75%. Hepatic veno-occlusive disease has been reported.

Before taking Asparaginase Erwinia Chrysanthemi Injection

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  • Tell your doctor if you ever had a serious allergic reaction to Erwinia asparaginase.
  • Tell them about past serious pancreatitis, clots or bleeding with asparaginase.
  • Severe liver impairment is a reason not to use it.
  • Pregnancy can be harmed by this drug; testing and non-hormonal birth control are advised.
  • Do not breastfeed during treatment and for 1 week after.
  • Not established in babies under 1 month.

What Asparaginase Erwinia Chrysanthemi Injection does in the body

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The way Rylaze's blood levels relate to its effects, and how those effects change over time, is unknown. Its action is based on depleting asparagine in the blood to kill leukemia cells.

How your body processes Asparaginase Erwinia Chrysanthemi Injection

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After a muscle injection, blood levels of Rylaze peak at a median of about 12 hours. About 37% is absorbed in healthy people. Its half-life is about 16 hours. The body is expected to break it down into small peptides.

Age, weight and sex did not meaningfully change how the body handled it once dosing was adjusted for body size. Black or African American patients cleared it about 29% more slowly. Effects of kidney or liver impairment have not been studied.

How to store Asparaginase Erwinia Chrysanthemi Injection

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Store RYLAZE vials refrigerated at 2°C to 8°C (36°F to 46°F) in the original carton to protect from light.

Written from the FDA-approved label with AI and reviewed by our pharmacy team. How we use AI →

Asparaginase Erwinia Chrysanthemi Injection: pharmacist answers to common questions

Quick, plain-English answers to the questions patients ask most about Asparaginase Erwinia Chrysanthemi Injection — the kind of thing our pharmacy team would talk through with you at the counter.

What is Rylaze for?

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It is used with other chemotherapy to treat acute lymphoblastic leukemia and lymphoblastic lymphoma. It is for people who developed an allergic-type reaction to E. coli-derived asparaginase. It is approved for adults and children 1 month or older.

How will I receive it?

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It is given as an injection into a muscle by a healthcare professional. Your team will follow a schedule such as every 48 hours or Monday, Wednesday and Friday. You will get medicines beforehand to help prevent allergic reactions.

What side effects should I expect?

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Common ones include nausea, tiredness, headache, muscle pain, infections, fever and abnormal liver tests. Bruising or nosebleeds can also happen. Your team will check blood tests regularly.

When should I call my care team right away?

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Call for swelling of the face or lips, hives, trouble breathing, severe belly pain, yellowing of the skin or eyes, rapid weight gain with belly swelling, unusual bleeding, or signs of a clot or infection. These can be serious.

Is it safe during pregnancy or breastfeeding?

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It can harm an unborn baby, so a pregnancy test is recommended first. Use effective non-hormonal birth control during treatment and for 3 months after the last dose. Do not breastfeed during treatment and for 1 week after.

Is Asparaginase Erwinia Chrysanthemi Injection available over the counter?

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No. Asparaginase Erwinia Chrysanthemi Injection is a prescription medicine: every Asparaginase Erwinia Chrysanthemi Injection product listed with the FDA is prescription only, so it is not sold over the counter. Your prescriber decides whether it is appropriate for you, and your pharmacist dispenses it.

When was Asparaginase Erwinia Chrysanthemi Injection first available?

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The earliest FDA record we hold for Asparaginase Erwinia Chrysanthemi Injection is from 2021: its first approval in Drugs@FDA or its earliest product listing in the NDC Directory, whichever is older. Many older medicines were in use before their first formal FDA approval, so this is the earliest date on record, not necessarily when Asparaginase Erwinia Chrysanthemi Injection was first used.

Answers drafted from the FDA-approved label with AI and reviewed by our pharmacy team. How we use AI →

More about Asparaginase Erwinia Chrysanthemi Injection on HelloPharmacist

Detailed data & references for Asparaginase Erwinia Chrysanthemi Injection Forms & strengths, pricing, billing codes, manufacturers, safety reports and sourcing — the data behind the page. Most people can stop here. Each section below opens on a tap.

Asparaginase Erwinia Chrysanthemi Injection forms and strengths (how it comes)

Asparaginase Erwinia Chrysanthemi Injection 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.

Need a version that does not list lactose, a gluten source, a dye or gelatin? Inactive ingredients differ by manufacturer: see Asparaginase Erwinia Chrysanthemi Injection inactive ingredients by manufacturer.

Injection

By injection · Into a muscle
Brands Rylaze
How this form is used
What it may be used for
  • Rylaze is used with other chemotherapy for acute lymphoblastic leukemia and lymphoblastic lymphoma in people 1 month or older who became hypersensitive to E. coli-derived asparaginase.
Important instructions
  • Rylaze is given by intramuscular injection only; the intravenous route is not approved.
  • Rylaze is given every 48 hours or on a Monday/Wednesday/Friday schedule, as a replacement for a long-acting asparaginase.
  • Rylaze doses are preceded by premedicines to reduce allergic reactions.
  • Rylaze injection sites are rotated, and large doses are split across more than one site.
Available strengths 1 strength
4 FDA-listed product records ⓘ

Asparaginase Erwinia Chrysanthemi Injection on the U.S. market: products, makers and brands

How Asparaginase Erwinia Chrysanthemi Injection 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.

1 company lists 1 Asparaginase Erwinia Chrysanthemi Injection product record with the FDA, mostly as injection; the earliest marketing or approval year on record is 2021. Brand names on the directory include Erwinaze, Rylaze; the rest are generics.

1
Dose forms ⓘ
1
Labelers (makers, repackagers, distributors)
1
Brand names
1
FDA-listed product records ⓘ
2021
Earliest FDA record ⓘ

How widely Asparaginase Erwinia Chrysanthemi Injection is used (Medicaid data)

A general measure of how commonly Asparaginase Erwinia Chrysanthemi Injection is prescribed, based on Medicaid — one of the largest public drug programs. The figure below is prescriptions filled in Q2 2025 – Q1 2026, summed across every form and brand of the drug.

Think of this as a proxy for how widely Asparaginase Erwinia Chrysanthemi Injection 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.

1,281
Medicaid prescriptions filled (Q2 2025 – Q1 2026)
$11.3M gross Medicaid reimbursement (before mandatory rebates — net cost is lower)

How commonly is Asparaginase Erwinia Chrysanthemi Injection prescribed? Of the 1,601 medications we measure, Asparaginase Erwinia Chrysanthemi Injection ranks #1,254 by Medicaid prescriptions — more than 22% of them.

Where Asparaginase Erwinia Chrysanthemi Injection ranks among the drugs we measure · Q2 2025 – Q1 2026 · neighbors ±5

Source: Medicaid State Drug Utilization Data (CMS), aggregated by generic ingredient — summed across every NDC (all brands, strengths, salt forms and dosage forms) of Asparaginase Erwinia Chrysanthemi Injection, 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 2 listed Asparaginase Erwinia Chrysanthemi Injection NDCs with Medicaid activity.

Compare Asparaginase Erwinia Chrysanthemi Injection products

A representative set of FDA-listed product records for Asparaginase Erwinia Chrysanthemi Injection — 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
20 mg/mL Intramuscular Jazz Pharmaceuticals, Inc. BLA View NDC →

Showing 1 of 1 products — FDA National Drug Code Directory. See every product, package size and price: browse all 1 Asparaginase Erwinia Chrysanthemi Injection NDCs →

Asparaginase Erwinia Chrysanthemi Injection 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.

The FDA’s enforcement reports list no Asparaginase Erwinia Chrysanthemi recalls since July 2021.

✅No Asparaginase Erwinia Chrysanthemi recalls on record since July 2021

Source: FDA enforcement (recall) reports, via openFDA; our copy was last updated Sep 24, 2026.

Asparaginase Erwinia Chrysanthemi Injection brand names

Asparaginase Erwinia Chrysanthemi Injection is sold under 2 brand names in the FDA directory — Erwinaze, Rylaze. A brand and its generic contain the same active ingredient; the brand name belongs to one company's product.

Erwinaze Rylaze

Who makes Asparaginase Erwinia Chrysanthemi Injection: manufacturers and labelers

One company lists Asparaginase Erwinia Chrysanthemi Injection products with the FDA. By number of product records, the largest are Jazz Pharmaceuticals, Inc.. Labelers include manufacturers and repackagers; the product in your bottle depends on which one your pharmacy stocks.

Jazz Pharmaceuticals, Inc. 1

Asparaginase Erwinia Chrysanthemi Injection drug class (RxNorm)

Asparaginase Erwinia Chrysanthemi Injection belongs to the Asparagine-specific Enzyme class.

Pharmacologic class Asparagine-specific Enzyme
Drug family (ATC) Other antineoplastic agents

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.

Sources for this Asparaginase Erwinia Chrysanthemi Injection page

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.

📄
FDA-filed drug labels (SPL) Uses, dosing, warnings & side effects from SPL records retrieved through openFDA; the linked representative set can be verified on DailyMed. ✓ Linked label effective Jul 1, 2025
🏭
Forms, brands & labelersAggregated from ingredient-matched FDA National Drug Code Directory product records for Asparaginase Erwinia Chrysanthemi Injection.
📈
Real-world reportsThe FDA Adverse Event Reporting System (FAERS), served through openFDA.
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Recalls & shortagesopenFDA drug-enforcement reports and the FDA drug-shortage database.
🧾 Clinical label set — FDA-filed SPL labels retained for Asparaginase Erwinia Chrysanthemi Injection after exact ingredient or ingredient-combination matching and applicable route/form matching
Clinical labels in scope
1
Finished products in the current FDA directory
1
Companies listing them (makers, repackagers, distributors)
1
FDA labeler codes behind them ⓘ
1
Linked representative label ⓘ
Jazz Pharmaceuticals, Inc.
Linked label effective
Jul 1, 2025
Composite sections available
19
Linked SPL Set ID
857e53aa-1098-4dad-b654-0276cdd43e03
Linked SPL Document ID
cca29ff5-d000-43da-b64a-c65816a8a9c4
Open the linked representative label on DailyMed ↗

How this page is built

HelloPharmacist combines public FDA and NLM records and does not author the underlying clinical facts. The plain-language sections are written with AI from the FDA-approved label text and reviewed by our pharmacy team before publication. Jazz Pharmaceuticals, Inc. is the representative DailyMed label linked for verification and dates. This is general education, not medical advice: always talk to your doctor or pharmacist about your own medicines. How we build and review drug pages →