Myself, along with a small group of MS patients, are asking for your help.

We are gathering real-world experiences from people who have been switched from Tysabri IV (originator natalizumab) to Tyruko (biosimilar natalizumab) within the NHS.

This survey aims to better understand how this transition has affected patients—not just in terms of relapse control, but overall quality of life—and to present these findings directly to the NHS.

We are particularly interested in:

• Whether patients received clear information and discussion about biosimilars before the switch
• The level of patient involvement in decision-making and consent
• The support provided during the transition period
• Any changes or impacts on symptoms, wellbeing, and daily life
• The quality and adequacy of ongoing healthcare support

👉 Take the survey here:

https://eu.surveymars.com/q/mYiXLAABb

Why this matters

Clinical trial data on biosimilars like Tyruko is limited. The key study involved just 30 patients (29 completed), all of whom had only been on Tysabri IV for around 24 weeks before switching.

This does not reflect the reality for many of us.

Many patients had been stable on Tysabri IV for 10–15 years or more. From lived experience, we know it can take up to a year to feel the full benefit of the treatment—stronger symptoms control, improved energy, and a significantly better quality of life.

While both treatments may control relapses (which is vital), many patients report that after switching:

• Their symptoms worsened
• Their strength and stability declined
• Their overall quality of life diminished

Importantly:

• We did not expect this outcome
• We were not anticipating an inferior experience
• These changes have had serious, real-life consequences

Questions that need answering

• Can a short-term trial truly capture the long-term patient experience?
• Is relapse control alone enough, if quality of life is reduced?
• Are we overlooking what patients lose in the process?

The bigger picture

We understand the NHS must manage costs. However, the savings from switching medications must be weighed against the wider impact:

• Increased need for care and support
• More frequent and varied hospital appointments
• Greater reliance on physiotherapy and additional medications
• A decline in independence and wellbeing

For many, Tysabri IV was more than a treatment—it was a lifeline. It gave people a level of stability and quality of life they never thought possible after diagnosis.

Having that taken away has felt devastating.

If you’ve read this far, thank you. Your time and understanding truly matter.

If this affects you or someone you know, please consider completing and sharing the survey. Together, we can ensure patient voices are heard.