Sandoz's Biosimilar Tyruko Launches in US, Challenging Biogen's Tysabri

Sandoz has officially launched Tyruko, the first biosimilar to Biogen's multiple sclerosis (MS) treatment Tysabri, in the United States. This milestone marks a significant shift in the MS treatment landscape, potentially offering a more cost-effective option for patients while putting pressure on Biogen's blockbuster medication.

Tyruko's Market Entry and Implications

Tyruko's arrival in the US market comes after a two-year delay following its FDA approval in 2023. The biosimilar, developed by Polpharma Biologics and commercialized globally by Sandoz, is now available in both Tysabri's MS and Crohn's disease indications. Keren Haruvi, Sandoz's North America president, emphasized the launch as an "important opportunity to help people with MS navigate this disease in a way that is more cost-effective."

The introduction of Tyruko aligns with Sandoz's ambitions to become the leading biosimilar provider in the US and a global leader in MS treatment. Already available in 14 European countries, Tyruko is expected to be a key contributor to Sandoz's growth strategy.

Challenges and Preparations

Sandoz faced several hurdles in bringing Tyruko to market, including a legal challenge from Biogen in 2022, which was later dismissed by a federal court in Delaware. The launch was further delayed due to the need for FDA approval of a John Cunningham virus (JCV) antibody test, crucial for assessing the risk of progressive multifocal leukoencephalopathy (PML), a rare but serious brain infection associated with Tysabri use.

To address this requirement, Sandoz partnered with Labcorp to develop and validate a laboratory-developed test for detecting anti-JCV antibodies. Labcorp will offer the Tyruko JCV testing program at no cost to eligible patients, with Sandoz covering the test expenses.

Market Impact and Future Outlook

Biogen, which has been preparing for this scenario, remains confident in Tysabri's role in MS treatment. The company has seen slight gains in Tysabri-specific revenue during the third quarter of 2025, despite an overall decline in MS sales.

As the first US biosimilar for MS treatment, Tyruko's launch represents a significant milestone in the pharmaceutical industry. Its entry into the market is likely to intensify competition in the MS treatment space and potentially lead to more affordable options for patients. The long-term impact on Biogen's market share and the broader implications for MS treatment accessibility will be closely watched by industry observers in the coming months.