Reviewed by: HU Medical Review Board | Last reviewed: September 2023 | Last updated: September 2023
A biosimilar is a drug that is similar to another biologic drug. A biosimilar has no clinically proven differences from the biologic drug in its:1,2
You might think of a biosimilar as a “generic” drug. But generic drugs have chemically identical active ingredient(s) to the main drug. Biosimilars have natural variation because they are made from living cells. They are also more expensive to make than generic drugs.1,2
Tyruko is also approved to treat Crohn's disease.1,2
What are the ingredients in Tyruko?
The active ingredient in Tyruko is a monoclonal antibody called natalizumab-sztn.1
How does Tyruko work?
As a biosimilar, Tyruko works the same way as Tysabri. Tyruko contains monoclonal antibodies that bind to a particular receptor on the surface of certain white blood cells. Research suggests that blocking this receptor prevents these immune cells from crossing into the central nervous system (CNS). This prevents them from causing inflammation and damage to myelin and neurons in the CNS, which is the cause of MS.1,3
What are the possible side effects?
The most common side effects of Tyruko include:1,3
- Cold symptoms such as stuffy nose, sneezing, or sore throat
- Joint pain
- Infections of the urinary tract or lower respiratory (breathing) tract
Tyruko has a boxed warning, the strictest warning from the US Food and Drug Administration (FDA). It has this warning because, like Tysabri, it can increase your chances of developing progressive multifocal leukoencephalopathy (PML). PML is caused by a virus that infects the brain. It can cause severe disabilities or death. Your doctor can test your blood for evidence of this virus to help determine if Tyruko is a safe choice for you.1
These are not all the possible side effects of Tyruko. Talk to your doctor about what to expect when taking Tyruko. You also should call your doctor if you have any changes that concern you when taking Tyruko.1
Other things to know
Tyruko is put into a vein (given as an IV infusion). The infusion usually takes about an hour and is given every 4 weeks. A doctor will give the infusion.1
You should not take Tyruko if you:1
- Have or have had PML
- Are allergic to any ingredients in Tyruko
- Have a medical condition that can weaken your immune system, such as HIV, AIDS, leukemia, lymphoma, or an organ transplant
- Are taking medicines that can weaken your immune system
- Are pregnant or breastfeeding
Because of the risk linked to Tyruko, it is part of a restricted program called the MS Tyruko REMS program. Only registered doctors, infusion centers, and pharmacies can prescribe, distribute, or give Tyruko. You also must talk to your doctor and understand the benefits and risks of Tyruko and agree to all the instructions.1
Before beginning treatment for MS, tell your doctor about all your health conditions and any other drugs, vitamins, or supplements you are taking. This includes over-the-counter drugs.
For more information, read the full prescribing information of Tyruko.