Tyruko® (natalizumab-sztn) injection, the first biosimilar for Tysabri® (natalizumab – Biogen), was approved by the U.S. Food and Drug Administration (FDA) on Aug. 24, 2023. The integrin receptor agonist is approved for treating relapsing forms of multiple sclerosis (MS) and Crohn’s disease (CD) that have not responded to previous treatment. Once every four weeks, it is infused intravenously (IV) by a healthcare provider in a facility where the patient can be monitored for any severe reactions during the infusion and for an hour or longer after at least the first 12 treatments. Due to the possibility that it may cause progressive multifocal leukoencephalopathy (PML), a rare and potentially fatal viral infection of the brain, Tyruko has a boxed warning and a risk evaluation and mitigation strategy (REMS) that limits its prescribing and dispensing. The Sandoz division of Novartis will begin marketing it “as soon as possible”. An exact launch date and pricing information have not been announced. Full prescribing information for Tyruko is here.
At a Glance
- Brand (Generic) Name: Tyruko (natalizumab-sztn)
- Manufacturer: Sandoz
- Date Approved: Aug. 24, 2023
- Indications: as monotherapy for relapsing forms of MS, including clinically isolated syndrome (CIS), relapsing-remitting MS (RRMS), and active secondary progressive disease (SPMS) and for inducing and maintaining clinical response and remission in adults who have moderate-to-severe active CD inflammation who have had an inadequate response to, or who are unable to tolerate, conventional CD therapies
- Dosage Forms Available: single-dose, 300mg vials
- Launch Date: Not available
- Estimated Annual Cost: Not available
- MS is an autoimmune condition that destroys myelin sheaths (protective coverings on nerve cells) in the central nervous system (CNS). About two-thirds of patients are women and most patients are diagnosed between 20 years and 50 years of age.
- According to the National MS Society, RRMS is the most common form — affecting about 85% of the estimated one million Americans who have the disease. Patients with RRMS have periods of active symptoms alternating with periods of little or no disease activity. As many as 80% of patients who have RRMS eventually will progress to SPMS, which worsens gradually without definite relapses and remissions.
- With an estimated 500,000 patients in the U.S., CD is an inflammatory bowel disease (IBD) that causes inflammation and irritation in the digestive tract – most commonly in the intestines. Typically diagnosed in early adulthood, CD can lead to abscesses, fistulas, and obstructions in the intestines.
- By blocking specific proteins, Tyruko keeps leucocytes from migrating out of blood vessels, so they cannot attach to cells inside the CNS or intestines where they cause inflammation.
- The REMS for Tyruko requires healthcare providers to be certified in administering Tyruko. Patients must join the program and be evaluated three months after their first infusions and then every six months until six months after treatment stops.
- PML, which is increased for patients who have had prior treatment with immunosuppressants and for those using Tyruko for longer than two years, can result in severe disability or death. Patients, caregivers, and health professionals should be alert for cognitive decline, personality changes, visual disturbances, and weakness on one body side that could be signs of PML.
- Other serious side effects may include immunosuppression, liver damage, and low platelet counts.
- Natalizumab is the only drug in its therapy class.
- In 2022, Tysabri’s total sales amounted to about $2 billion.