Natalizumab-sztn

What Natalizumab-sztn is used for

Quoted from the “Indications and Usage” section of the FDA-approved label.

TYRUKO is an integrin receptor antagonist indicated for treatment of: Multiple Sclerosis (MS) TYRUKO is indicated as monotherapy for the treatment of relapsing forms of multiple sclerosis, to include clinically isolated syndrome, relapsing-remitting disease, and active secondary progressive disease, in adults. Natalizumab products increase the risk of PML […]. …

— FDA label: Tyruko, Sandoz Inc, effective October 31, 2025. Read the full label on DailyMed →

Label quoted: the one for the most common form (injection, intravenous), Tyruko, Sandoz Inc; it covers 1 product in the FDA NDC Directory. The side effects, interactions, dosage and pregnancy quotes below come from this same label.

This page is not medical advice. Talk to your doctor or pharmacist before you start, stop or change any medicine.

Conditions named on the label

These condition names appear word for word in the label’s “Indications and Usage” text (matched with a reviewed table). Each page lists hospitals whose own websites name the condition.

Related medical specialties

Boxed warning

A boxed warning (“black box”) is the FDA’s strongest warning on a drug label, for serious or life-threatening risks.

This label has a boxed warning. Its heading: WARNING: PROGRESSIVE MULTIFOCAL LEUKOENCEPHALOPATHY. Read it on the full label →

Natalizumab-sztn boxed warning: what the label says

Quoted from the boxed warning of the FDA-approved label.

WARNING: PROGRESSIVE MULTIFOCAL LEUKOENCEPHALOPATHY Natalizumab products increase the risk of progressive multifocal leukoencephalopathy (PML), an opportunistic viral infection of the brain that usually leads to death or severe disability. Risk factors for the development of PML include the presence of anti-JCV antibodies, duration of therapy, and prior use of immunosuppressants.

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These factors should be considered in the context of expected benefit when initiating and continuing treatment with TYRUKO [see Warnings and Precautions (5.1)]. - Healthcare professionals should monitor patients on TYRUKO for any new sign or symptom that may be suggestive of PML. TYRUKO dosing should be withheld immediately at the first sign or symptom suggestive of PML. For diagnosis, an evaluation that includes a gadolinium-enhanced magnetic resonance imaging (MRI) scan of the brain and, when indicated, cerebrospinal fluid analysis for JC viral DNA are recommended [see Contraindications (4), Warnings and Precautions (5.1)]. - Because of the risk of PML, TYRUKO is available only through a restricted program under a Risk Evaluation and Mitigation Strategy (REMS) called the TYRUKO REMS Program [see Warnings and Precautions (5.2)]. WARNING: PROGRESSIVE MULTIFOCAL LEUKOENCEPHALOPATHY See full prescribing information for complete boxed warning

• Natalizumab products increase the risk of progressive multifocal leukoencephalopathy (PML), an opportunistic viral infection of the brain that usually leads to death or severe disability (5.1).
• Risk factors for the development of PML include the presence of anti-JCV antibodies, duration of therapy, and prior use of immunosuppressants. These factors should be considered in the context of expected benefit when initiating and continuing treatment with TYRUKO (5.1).
• Monitor patients, and withhold TYRUKO immediately at the first sign or symptom suggestive of PML (4, 5.1).
• Because of the risk of PML, TYRUKO is available only through a restricted distribution program called the TYRUKO REMS Program (5.1, 5.2).

— FDA label: Tyruko, Sandoz Inc, effective October 31, 2025. Read the full label on DailyMed →

Natalizumab-sztn side effects

Quoted from the “Adverse Reactions” section of the FDA-approved label. Tell your doctor about any side effect that worries you.

The following serious adverse reactions are described below and elsewhere in the labeling:

• Progressive Multifocal Leukoencephalopathy (PML) [see Warnings and Precautions (5.1)]
• Herpes Infections [see Warnings and Precautions (5.3)]
• Hepatotoxicity [see Warnings and Precautions (5.4)]
• Hypersensitivity/Antibody Formation [see Warnings and Precautions (5.5)]
• Immunosuppression/Infections [see Warnings and Precautions (5.6)]
• Hematological Abnormalities [see Warnings …

— FDA label: Tyruko, Sandoz Inc, effective October 31, 2025. This is part of the section. Read the full label on DailyMed →

Natalizumab-sztn drug interactions

Quoted from the “Drug Interactions” section of the FDA-approved label. Tell your pharmacist about every medicine, vitamin and herbal product you take.

Because of the potential for increased risk of PML and other infections, Crohn’s disease patients receiving natalizumab products should not be treated with concomitant immunosuppressants (e.g., 6‑ mercaptopurine, azathioprine, cyclosporine, or methotrexate) or inhibitors of TNF-α, and corticosteroids should be tapered in those patients with Crohn’s disease who are on chronic corticosteroids when they start TYRUKO therapy [see Indications and Usage (1.2) and Warnings and Precautions (5.1, 5.6)].

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Ordinarily, MS patients receiving chronic immunosuppressant or immunomodulatory therapy should not be treated with TYRUKO [see Indications and Usage (1.1) and Warnings and Precautions (5.1, 5.6)].

— FDA label: Tyruko, Sandoz Inc, effective October 31, 2025. Read the full label on DailyMed →

Natalizumab-sztn dosage

Quoted from the “Dosage and Administration” section of the FDA-approved label. Your own dose is the one your doctor prescribes: do not change it on your own.

• 300 mg infused intravenously over one hour, every four weeks. Do not give as an intravenous push or bolus. (2.1, 2.2)
• TYRUKO solution must be administered within 4 hours of preparation. (2.3)
• Observe patients during all infusions. Post-infusion, for the first 12 infusions, observe patients for one hour after the infusion is complete.

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For patients who have received 12 infusions without evidence of a hypersensitivity reaction, observe patients post-infusion for the 13th and subsequent infusions according to clinical judgment. (2.4)

• In CD, discontinue in patients that have not experienced therapeutic benefit by 12 weeks of induction therapy, and in patients that cannot discontinue chronic concomitant steroids within six months of starting therapy. (2.2) 2.1 Multiple Sclerosis (MS) Only prescribers registered in the MS TYRUKO REMS Program may prescribe TYRUKO for multiple sclerosis [see Warnings and Precautions (5.2)]. The recommended dose of TYRUKO for multiple sclerosis is 300 mg intravenous infusion over one hour every four weeks. 2.2 Crohn's Disease (CD) Only prescribers registered in the CD TYRUKO REMS Program may prescribe TYRUKO for Crohn’s disease [see Warnings and Precautions (5.2)]. The recommended dose of TYRUKO for Crohn’s disease is 300 mg intravenous infusion over one hour every four weeks. TYRUKO should not be used with concomitant immunosuppressants (e.g., 6-mercaptopurine, azathioprine, cyclosporine, or methotrexate) or concomitant inhibitors of TNF-α. Aminosalicylates may be continued during treatment with TYRUKO. If the patient with Crohn’s disease has not experienced therapeutic benefit by 12 weeks of induction therapy, discontinue TYRUKO. For patients with Crohn’s disease who start TYRUKO while on chronic oral corticosteroids, commence steroid tapering as soon as a therapeutic benefit of TYRUKO has occurred; if the patient with Crohn’s disease cannot be tapered off of oral corticosteroids within six months of starting TYRUKO, discontinue TYRUKO. Other than the initial six-month taper, prescribers should consider discontinuing TYRUKO for patients who require additional steroid use that exceeds three months in a calendar year to control their Crohn’s disease. 2.3 Dilution Instructions 1. Use aseptic technique when preparing TYRUKO solution for intravenous infusion. Each vial is intended for single use only. Discard any unused portion. 2. TYRUKO is a colorless and clear to slightly opalescent solution. Inspect the TYRUKO vial for particulate material and discoloration prior to dilution and administration. If visible particulates are observed and/or the liquid in the vial is discolored, the vial must not be used. 3. To prepare the diluted solution, withdraw 15 mL of TYRUKO from the vial using a sterile needle and syringe. Inject TYRUKO into 100 mL of 0.9% Sodium Chloride Injection, USP. No other intravenous diluents may be used to prepare the TYRUKO diluted solution. 4. Gently invert the TYRUKO diluted solution to mix completely. Do not shake. Inspect the solution visually for particulate material prior to administration. 5.

— FDA label: Tyruko, Sandoz Inc, effective October 31, 2025. This is part of the section. Read the full label on DailyMed →

Natalizumab-sztn in pregnancy

Quoted from the pregnancy part of the FDA-approved label. Ask your doctor before you take any medicine while pregnant or planning a pregnancy.

Risk Summary There are no adequate data on the risk of major birth defects, miscarriage, or other adverse maternal outcomes associated with the use of natalizumab products in pregnant women. Adverse fetal outcomes of neonatal thrombocytopenia and anemia have been reported (see Clinical Considerations).

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In animal studies, administration of natalizumab during pregnancy produced fetal immunologic and hematologic effects in monkeys at doses similar to the human dose and reduced offspring survival in guinea pigs at doses greater than the human dose. These doses were not maternally toxic but produced the expected pharmacological effects in maternal animals (see Data). In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively. The background risk of major birth defects and miscarriage for the indicated population is unknown. Clinical Considerations Fetal/Neonatal Adverse Reactions Cases of neonatal thrombocytopenia and anemia in infants born to women exposed to natalizumab products during pregnancy were reported in the post-marketing setting [see Warnings and Precautions (5.8)]. Therefore, a CBC should be obtained in neonates who were exposed to TYRUKO in utero. Data Animal Data In developmental toxicity studies conducted in guinea pigs and monkeys, at natalizumab doses up to 30 mg/kg (7 times the recommended human dose based on body weight [mg/kg]), transplacental transfer and in utero exposure of the embryo/fetus was demonstrated in both species. In a study in which pregnant guinea pigs were administered natalizumab (0, 3, 10, or 30 mg/kg) by intravenous (IV) infusion on alternate days throughout organogenesis (gestation days [GD] 4‑30), no effects on embryofetal development were observed. When pregnant monkeys were administered natalizumab (0, 3, 10, or 30 mg/kg) by IV infusion on alternative days throughout organogenesis (GDs 20-70), serum levels in fetuses at delivery were approximately 35% of maternal serum natalizumab levels. There were no effects on embryofetal development; however, natalizumab-related immunological and hematologic changes were observed in the fetuses at the two highest doses. These changes included decreases in lymphocytes (CD3+ and CD20+), changes in lymphocyte subpopulation percentages, mild anemia, reduced platelet count, increased spleen weights, and reduced liver and thymus weights associated with increased splenic extramedullary hematopoiesis, thymic atrophy, and decreased hepatic hematopoiesis. In a study in which monkeys were exposed to natalizumab during pregnancy (IV infusion of 30 mg/kg) on alternate days from GD20 to GD70 or GD20 to term, abortions were increased approximately 2-fold compared to controls. In offspring born to mothers administered natalizumab on alternate days from GD20 until delivery, hematologic effects (decreased lymphocyte and platelet counts) were also observed. These effects were reversed upon clearance of natalizumab. There was no evidence of anemia in these offspring.

— FDA label: Tyruko, Sandoz Inc, effective October 31, 2025. This is part of the section. Read the full label on DailyMed →

When Natalizumab-sztn should not be used

Quoted from the “Contraindications” section of the FDA-approved label.

• TYRUKO is contraindicated in patients who have or have had progressive multifocal leukoencephalopathy (PML) [see Warnings and Precautions (5.1)].
• TYRUKO is contraindicated in patients who have had a hypersensitivity reaction to natalizumab products or any of the ingredients in TYRUKO. Observed reactions range from urticaria to anaphylaxis [see Warnings and Precautions (5.5)].

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• Patients who have or have had PML (4)
• Patients who have had a hypersensitivity reaction to natalizumab products (4, 5.3)

— FDA label: Tyruko, Sandoz Inc, effective October 31, 2025. Read the full label on DailyMed →

Natalizumab-sztn overdose

Quoted from the “Overdosage” section of the FDA-approved label. If someone may have taken too much, call Poison Help at 1-800-222-1222 (or 911 in an emergency).

Safety of doses higher than 300 mg has not been adequately evaluated. The maximum amount of natalizumab products that can be safely administered has not been determined.

— FDA label: Tyruko, Sandoz Inc, effective October 31, 2025. Read the full label on DailyMed →

Forms and how it is given

Companies that list this medicine

Labelers in the FDA NDC Directory: the company named on the package (maker or distributor), with the number of prescription products.

• Sandoz Inc1 product
• Biogen Inc.1 product

FDA approval history

• BLA: Biologics License Application: how a biologic medicine (made from living cells) is approved.

Shortage status

The FDA drug shortage list does not show these products.

FDA Drug Shortages database →

Recalls

No recall linked to these products (by their NDC code) appears in the FDA enforcement reports.

Official identifiers

Next steps

• Find a pharmacy near youAsk which price applies to you and whether your product is affected by a recall
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• TyrukoBrand page: products, maker and price
• TysabriBrand page: products, maker and price
• Multiple sclerosisCondition named on the label: hospitals that treat it
• Crohn's diseaseCondition named on the label: hospitals that treat it
• Sandoz IncMaker or distributor
• Biogen Inc.Maker or distributor
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Sources

1. FDA-approved label on DailyMed (National Library of Medicine) — Tyruko, Sandoz Inc, effective October 31, 2025; via openFDA, FDA data exported October 30, 2026, retrieved October 31, 2026
2. NDC Directory (openFDA) — U.S. Food and Drug Administration (FDA), FDA data exported October 30, 2026, retrieved October 31, 2026
3. Drugs@FDA (openFDA) — U.S. Food and Drug Administration (FDA), FDA data exported October 30, 2026, retrieved October 31, 2026
4. Drug recall enforcement reports (openFDA) — U.S. Food and Drug Administration (FDA), FDA data exported October 27, 2026, retrieved October 31, 2026
5. Drug shortages (openFDA) — U.S. Food and Drug Administration (FDA), FDA data exported October 30, 2026, retrieved October 31, 2026

openFDA data is provided by the FDA as is; it may be incomplete. Always rely on the label that comes with your medicine. FDA Enforcement Report search →

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