FIND ANSWERS TO FREQUENTLY ASKED QUESTIONS

What is TYSABRI used for?

TYSABRI 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. TYSABRI increases the risk of progressive multifocal leukoencephalopathy (PML.). When initiating and continuing treatment with TYSABRI, physicians should consider whether the expected benefit of TYSABRI is sufficient to offset this risk.1

Learn More About TYSABRI

What is natalizumab?

Natalizumab is the generic name for the FDA-approved monoclonal antibody marketed under the brand name TYSABRI.

FDA=Food and Drug Administration.

Please see the full Prescribing Information, including Boxed Warning and Medication Guide.

Is a biosimilar the same as generic?

No, a biosimilar is not the same as a generic, which has the same exact active ingredient as its reference product. A biosimilar is FDA-approved to have no clinically meaningful differences in efficacy, safety, and immunogenicity, but is not exactly the same as an already-approved biological medicine.

Unlike a generic, under many current state laws a biosimilar cannot be automatically substituted at the pharmacy without consulting the prescriber unless classified as an interchangeable biosimilar.3,4

FDA=Food and Drug Administration.

Are the biosimilar natalizumab and TYSABRI® interchangeable?

An interchangeable biological product is a biosimilar that meets additional requirements and may be substituted for the originator or reference product at the pharmacy level, depending on state pharmacy laws. The biosimilar natalizumab has not received interchangeability designation at this time. Without interchangeability designation, under current state laws, the biosimilar cannot be automatically substituted for TYSABRI. If you have questions, please contact the biosimilar manufacturer representative for details.4-6

Is there a REMS program for TYSABRI?

Because of the risk of progressive multifocal leukoencephalopathy (PML), TYSABRI is available only through a restricted program under a Risk Evaluation and Mitigation Strategy (REMS) called the TOUCH® Prescribing Program.

Learn More About REMS: TOUCH Prescribing Program

How do patients take TYSABRI?

TYSABRI is a 1-hour IV infusion administered once every 4 weeks.1

  • Recommended dose: 300 mg infusion every 4 weeks
  • No premedication is required prior to infusion but may be administered based upon clinical judgment
  • Postinfusion observation: If no evidence of hypersensitivity reaction is observed after the first 12 infusions, a 1-hour postinfusion observation period is no longer required and is according to clinical judgment
    • If postinfusion observation is no longer required, total appointment time may be reduced by up to 50%
    • Total appointment time = infusion + observation

Remember: Only orders from infusion centers and certified pharmacies enrolled in and authorized by the TOUCH Prescribing Program will be processed. Contact Biogen at 1-800-456-2255.

IV=intravenous.

Learn More About Dosing

What is the infusion protocol for TYSABRI?
  • Infuse TYSABRI 300 mg in 100 mL 0.9% Sodium Chloride Injection, USP, over ~1 hour (infusion rate ~5 mg/minute)1
    • Allow solution to warm to room temperature prior to infusion
    • Do not administer TYSABRI as an IV push or bolus injection
    • After the infusion is complete, flush with 0.9% Sodium Chloride Injection, USP
  • Observe patients during the infusion and for 1 hour after the infusion is complete for the first 12 infusions1
    • Promptly discontinue the infusion upon the first observation of any signs or symptoms consistent with a hypersensitivity-type reaction
    • For patients who have shown no evidence of a hypersensitivity reaction, postinfusion observation is according to clinical judgment after the first 12 infusions
  • Use of filtration devices during administration has not been evaluated. Other medications should not be injected into infusion set side ports or mixed with TYSABRI1

IV=intravenous.

How do patients/prescribers locate infusion centers?

Find an Infusion Center Near Your Patient

Where can I find information on TYSABRI's efficacy?

See Results From the AFFIRM Trial

What is TYSABRI's safety profile?

Find Out More About the TOUCH Prescribing Program

What is the PML risk for TYSABRI?

The risk of developing progressive multifocal leukoencephalopathy (PML) while on treatment with TYSABRI is <1% regardless of JCV Antibody status.1

  • JCV infection is required for the development of PML1
  • Previous immunosuppressant use and treatment duration with TYSABRI are PML risk factors for JCV Antibody+ patients1
  • Biogen offers free anti-JCV antibody testing (the STRATIFY™ JCV Antibody assay) to support regular monitoring

JCV=John Cunningham virus.

Find Out More About PML Risk

Can STRATIFY JCV® be used to assess PML risk for other products including a biosimilar natalizumab?

The STRATIFY JCV® DxSelectTM Antibody assay and its related risk algorithm were developed over an extended period of time with patients treated with TYSABRI® (natalizumab). Biogen has not conducted clinical studies on the use of the STRATIFY JCV Antibody assay with products other than TYSABRI.

The Stratify JCV Antibody assay was developed by Biogen for use with TYSABRI and is sponsored by Biogen. Since 2012, more than 2,000,000 STRATIFY JCV Antibody tests have been evaluated for use with TYSABRI. Biogen will continue to provide free STRATIFY JCV Antibody testing to all patients who are on or considering TYSABRI. Specific questions about JCV Antibody assay administration for the biosimilar natalizumab are best answered by the biosimilar manufacturer contact.6

JCV=John Cunningham virus.

Are there monitoring requirements for TYSABRI?
  • Healthcare professionals should monitor patients on TYSABRI for any new sign or symptom that may be suggestive of PML.1 Consider monitoring patients at high risk for PML more frequently
    • Patients should continue to be monitored for any new signs or symptoms that may be suggestive of PML for ~6 months after discontinuation of TYSABRI1
  • In TYSABRI-treated patients with PML, immune reconstitution inflammatory syndrome (IRIS) has been reported within days to several weeks after plasma exchange. Monitoring for development of IRIS and appropriate treatment of the associated inflammation should be undertaken1
  • Patients receiving TYSABRI should also be monitored for signs and symptoms of meningitis, encephalitis, acute retinal necrosis (ARN), hepatotoxicity, hypersensitivity reactions, and other infections, as well as JCV granule cell neuronopathy (GCN), that results in symptoms similar to PML and hemolytic anemia1
  • Biogen offers free anti-JCV antibody testing (the STRATIFY™ JCV Antibody assay) to support regular monitoring

JCV=John Cunningham virus; PML=progressive multifocal leukoencephalopathy.

Find Out More About PML Risk

Can patients take TYSABRI while pregnant or breastfeeding?

Before prescribing TYSABRI, ask your patients if they are pregnant or plan to become pregnant. It is not known if TYSABRI can harm fetal development; there are no adequate data on the risk associated with the use of TYSABRI in pregnant women. Cases of neonatal thrombocytopenia and anemia in infants born to women exposed to TYSABRI during pregnancy were reported in the post-marketing setting. Therefore, a CBC should be obtained in neonates who were exposed to TYSABRI in utero. Natalizumab has been detected in human milk. There are no data on the effects of this exposure on the breastfed infant or the effects of the drug on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for TYSABRI and any potential adverse effects on the breastfed infant from TYSABRI or from the underlying maternal condition.1

Please see full Prescribing Information, including Boxed Warning.

What financial assistance options are available for patients?

When cost may be a concern for your patients taking TYSABRI, Biogen may be able to help them access their prescription.

We will work with your patients based on their individual needs. Biogen Support Services offers a variety of different financial and insurance resources, including:

  • Communicating with insurance companies to clarify and confirm coverage, including assistance with the Prior Authorization process and denied claims
  • Insurance counseling that educates uninsured and underinsured patients on government insurance programs
  • Financial assistance options, including:
    • The Biogen Copay Program, which may lower medication cost for eligible patients with commercial insurancea
    • Other possible financial assistance, where applicable
  • Reimbursement services to provide coverage support in the administration of TYSABRI
  • An Infusion Copay Assistance Program for eligible patients

Help Your Patients Get Support
Your patients can call 1-800-456-2255 Monday-Friday from 8:30 AM to 8 PM ET. Hablamos español.

aThere is an annual cap on the amount of assistance that patients can receive over a one-year period. Federal and state laws and other factors may prevent or otherwise restrict eligibility. People covered by Medicare, Medicaid, the VA/DoD, or any other federal plans are not eligible to enroll. Patients are eligible to enroll in the Biogen Copay Program for as long as it is offered and they are treated with a Biogen relapsing MS medication.

Download the Access and Reimbursement Guide.

Indication

TYSABRI® (natalizumab) 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. TYSABRI increases the risk of PML. When initiating and continuing treatment with TYSABRI, physicians should consider whether the expected benefit of TYSABRI is sufficient to offset this risk.

IMPORTANT SAFETY INFORMATION

WARNING: Progressive Multifocal Leukoencephalopathy (PML)

TYSABRI® (natalizumab) increases the risk of 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. These factors should be considered in the context of expected benefit when initiating and continuing treatment with TYSABRI.

Healthcare professionals should monitor patients on TYSABRI for any new sign or symptom that may be suggestive of PML. TYSABRI dosing should be withheld immediately at the first sign or symptom suggestive of PML. For diagnosis, an evaluation including a gadolinium-enhanced MRI scan of the brain and, when indicated, cerebrospinal fluid analysis for JC viral DNA are recommended.

Because of the risk of PML, TYSABRI is available only through a restricted program under a Risk Evaluation and Mitigation Strategy (REMS) called the TOUCH® Prescribing Program.

  • Infection by the JC Virus (JCV) is required for the development of PML
  • There are no known interventions that can reliably prevent PML or that can adequately treat PML if it occurs
  • Postmarketing data suggest that the risk of developing PML may be associated with relative levels of serum anti-JCV antibody compared to a calibrator as measured by ELISA (often described as an anti-JCV antibody index value)
  • MRI findings may be apparent before clinical signs or symptoms suggestive of PML. Monitoring with MRI for signs that may be consistent with PML may be useful, and any suspicious findings should lead to further investigation to allow for an early diagnosis of PML, if present. Consider monitoring patients at high risk for PML more frequently. Lower PML-related mortality and morbidity have been reported following TYSABRI discontinuation in patients with PML who were initially asymptomatic compared to patients with PML who had characteristic clinical signs and symptoms at diagnosis
  • PML has been reported after discontinuation of TYSABRI in patients who did not have findings suggestive of PML at the time of discontinuation. Patients should continue to be monitored for any new signs or symptoms that may be suggestive of PML for at least 6 months after discontinuation of TYSABRI
  • Adverse events that may occur during plasma exchange (PLEX) include clearance of other medications and volume shifts, which have the potential to lead to hypotension or pulmonary edema. Although PLEX has not been prospectively studied in TYSABRI-treated patients with PML, it has been used in such patients in the postmarketing setting to remove TYSABRI more quickly from the circulation. There is no evidence that PLEX has any benefit in the treatment of opportunistic infections such as PML
  • JCV infection of granule cell neurons in the cerebellum, i.e., JCV granule cell neuronopathy (GCN), with symptoms similar to PML, has been reported in patients treated with TYSABRI. JCV GCN can occur with or without concomitant PML and can cause cerebellar dysfunction. Diagnosis and management of JCV GCN should follow guidance provided for PML
  • Immune reconstitution inflammatory syndrome (IRIS) has been reported in the majority of TYSABRI-treated patients who developed PML and subsequently discontinued TYSABRI. In almost all cases, IRIS occurred after PLEX was used to eliminate circulating TYSABRI. It presents as a clinical decline in the patient’s condition after TYSABRI removal (and, in some cases, after apparent clinical improvement) that may be rapid, can lead to serious neurological complications or death, and is often associated with characteristic changes in the MRI. TYSABRI has not been associated with IRIS in patients discontinuing treatment with TYSABRI for reasons unrelated to PML. In TYSABRI-treated patients with PML, IRIS has been reported within days to several weeks after PLEX. Monitoring for development of IRIS and appropriate treatment of the associated inflammation should be undertaken

Contraindications

  • TYSABRI is contraindicated in patients who have or have had PML
  • TYSABRI is contraindicated in patients who have had a hypersensitivity reaction to TYSABRI

TYSABRI TOUCH Prescribing Program

  • Because of the risk of PML, TYSABRI is available only through a restricted distribution program under a REMS called the TOUCH® Prescribing Program
  • Patients must be enrolled in the TOUCH Prescribing Program, read the Medication Guide, understand the risks associated with TYSABRI, and complete and sign the Patient Enrollment Form

Herpes Infections – Encephalitis, Meningitis and Acute Retinal Necrosis

  • TYSABRI increases the risk of developing encephalitis and meningitis caused by herpes simplex and varicella zoster viruses
  • Serious, life-threatening, and sometimes fatal cases have been reported in the postmarketing setting in multiple sclerosis patients receiving TYSABRI
  • The duration of treatment with TYSABRI prior to onset ranged from a few months to several years
  • Monitor patients receiving TYSABRI for signs and symptoms of meningitis and encephalitis. If herpes encephalitis or meningitis occurs, TYSABRI should be discontinued, and appropriate treatment for herpes encephalitis/meningitis should be administered
  • Patients being administered TYSABRI are at a higher risk of acute retinal necrosis (ARN), a fulminant viral infection of the retina caused by the family of herpes viruses. Patients with eye symptoms such as decreased visual acuity, redness or eye pain should be referred for retinal screening as serious cases of ARN can lead to blindness of one or both eyes
  • Following clinical diagnosis of ARN, consider discontinuation of TYSABRI

Hepatotoxicity

  • Clinically significant liver injury, including acute liver failure requiring transplant, has been reported in patients treated with TYSABRI in the postmarketing setting
  • Signs of liver injury, including markedly elevated serum hepatic enzymes and elevated total bilirubin, occurred as early as six days after the first dose; signs of liver injury have also been reported for the first time after multiple doses
  • TYSABRI should be discontinued in patients with jaundice or other evidence of significant liver injury (e.g., laboratory evidence)

Hypersensitivity/Antibody Formation

  • Hypersensitivity reactions have occurred in patients receiving TYSABRI, including serious systemic reactions (e.g., anaphylaxis) which occurred at an incidence of <1%
  • Reactions usually occur within 2 hours of the start of the infusion. Symptoms associated with these reactions can include urticaria, dizziness, fever, rash, rigors, pruritus, nausea, flushing, hypotension, dyspnea, and chest pain
  • If a hypersensitivity reaction occurs, discontinue administration of TYSABRI and initiate appropriate therapy. Patients who experience a hypersensitivity reaction should not be re-treated with TYSABRI
  • Hypersensitivity reactions were more frequent in patients with antibodies to TYSABRI compared with patients who did not develop antibodies to TYSABRI in both MS and CD studies
  • Patients who receive TYSABRI for a short exposure (1 to 2 infusions) followed by an extended period without treatment are at higher risk of developing anti-natalizumab antibodies and/or hypersensitivity reactions on re-exposure, compared to patients who received regularly scheduled treatment

Immunosuppression/Infections

  • The immune system effects of TYSABRI may increase the risk for infections
  • In Study MS1, certain types of infections—including pneumonias and urinary tract infections (including serious cases), gastroenteritis, vaginal infections, tooth infections, tonsillitis, and herpes infections—occurred more often in TYSABRI-treated patients than in placebo-treated patients. One opportunistic infection, a cryptosporidial gastroenteritis with a prolonged course, was observed in a patient who received TYSABRI in Study MS1
  • In Studies MS1 and MS2, an increase in infections was seen in patients concurrently receiving short courses of corticosteroids. However, the increase in infections in TYSABRI-treated patients who received steroids was similar to the increase in placebo-treated patients who received steroids
  • In a long-term safety study of patients, opportunistic infections (pulmonary mycobacterium avium intracellulare, aspergilloma, cryptococcal fungemia and meningitis, and Candida pneumonia) have been observed in <1% of TYSABRI-treated patients
  • Concurrent use of antineoplastic, immunosuppressant, or immunomodulating agents may further increase the risk of infections over the risk observed with use of TYSABRI alone
  • In Studies MS1 and MS2, the rate of any type of infection was approximately 1.5 per patient-year in both TYSABRI-treated patients and placebo-treated patients
  • In Study MS1, the incidence of serious infections was approximately 3% in TYSABRI-treated patients and in placebo-treated patients. Most patients did not interrupt treatment with TYSABRI during infections

Laboratory Test Abnormalities

  • In clinical trials, TYSABRI was observed to induce increases in circulating lymphocytes, monocytes, eosinophils, basophils, and nucleated red blood cells. Observed changes persisted during TYSABRI exposure, but were reversible, returning to baseline levels usually within 16 weeks after the last dose. Elevations of neutrophils were not observed. TYSABRI induces mild decreases in hemoglobin levels (mean decrease of 0.6 g/dL) that are frequently transient

Hematologic Abnormalities

  • Cases of thrombocytopenia, including immune thrombocytopenic purpura (ITP), have been reported with the use of TYSABRI in the postmarketing setting. Symptoms of thrombocytopenia may include easy bruising, abnormal bleeding, and petechiae. Delay in the diagnosis and treatment of thrombocytopenia may lead to serious and life-threatening sequelae. If thrombocytopenia is suspected, TYSABRI should be discontinued
  • Cases of neonatal thrombocytopenia and anemia have been reported in newborns with in utero exposure to TYSABRI. A CBC should be obtained in neonates with in utero exposure to TYSABRI

Adverse Reactions

  • The most common adverse reactions reported at an incidence of ≥10% with TYSABRI and ≥2% difference with placebo were headache (38% vs 33%), fatigue (27% vs 21%), infusion reactions (24% vs 18%), urinary tract infections (21% vs 17%), arthralgia (19% vs 14%), depression (19% vs 16%), pain in extremity (16% vs 14%), rash (12% vs 9%), gastroenteritis (11% vs 9%), and vaginitis (10% vs 6%)
  • The most frequently reported serious adverse reactions in Study MS1 were infections (3.2% vs 2.6% placebo), including urinary tract infection (0.8% vs 0.3%) and pneumonia (0.6% vs 0%), acute hypersensitivity reactions (1.1% vs 0.3%, including anaphylaxis/anaphylactoid reaction [0.8% vs 0%]), depression (1.0% vs 1.0%, including suicidal ideation or attempt [0.6% vs 0.3%]), and cholelithiasis (1.0% vs 0.3%)
  • Based on animal data, TYSABRI may cause fetal harm. TYSABRI should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus

Please see full Prescribing Information, including Boxed Warning.

References: 1. TYSABRI. Prescribing information. Biogen; 2025. 2. Polman CH, O'Connor PW, Havrdova E, et al; AFFIRM Investigators. 3. US Food and Drug Administration. Biosimilars info sheet. 2023. Accessed May 31, 2024. https://www.fda.gov/media/154912/download 4. US Food and Drug Administration. Biosimilar regulatory review and approval. 2023. Accessed May 31, 2024. https://www.fda.gov/media/151061/download 5. Tyruko vs. Tysabri for Multiple Sclerosis: 5 Similarities and Differences to Know. Published November 9, 2023. Accessed May 31, 2024. https://www.goodrx.com/conditions/multiple-sclerosis/tyruko-vs-tysabri 6. Data on file, Biogen.

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