Zilbrysq

Pharmaceutical company: UCB Pharma

To move, signals are sent from the brain, down specialised cells called nerves to the muscle. Acetylcholine receptors play a key role in passing the signal from nerve cells to the muscle. In myasthenia gravis, the immune system attacks the acetylcholine receptors. This means the nerve cells struggles to send strong signals to muscles, leading to muscle weakness.

When the immune system attacks the acetylcholine receptors it activates a part of the immune system called the complement system. This promotes inflammation. Normally this inflammation can help the body fight off infections, but in myasthenia gravis it can lead to damage to muscles. Zilbrysq works by blocking the activation of the complement system.

Zilbrysq comes as a liquid and is administered through an injection under the skin (subcutaneous injection).

Zilbrysq is approved for NHS use in Scotland.

Zilbrysq may be available through an early access scheme in England, Wales and Northern Ireland. For more information, please get in touch with your clinician.

In August 2026, Zilbrysq was accepted for NHS use in Scotland for those with refractory myasthenia gravis. If you are struggling to access Zilbrysq, please contact us on campaigns@musculardystrophyuk.org.

The National Institute for Health and Care Excellence (NICE), who decide if a treatment should be approved for NHS use in England, have been reviewing Zilbrysq for three years and have still not come to a final decision. Wales and Northern Ireland typically follow NICE decisions.

In June 2025, the National Institute for Health and Care Excellence (NICE) has confirmed Zilbrysq will not be funded. This means it will not be available on the NHS in England, Wales and Northern Ireland. While NICE acknowledged that Zilbrysq can “improve symptoms and people’s ability to carry out their normal activities”, NICE decided that the benefit it offers isn’t currently enough to justify the cost to the NHS. Read about NICE’s assessment.

Together with UCB, myaware, and the Association of British Neurologists (ABN), we appealed this decision, as we believe NICE did not act fairly or reasonably. In January 2026, our appeal against the decision not to fund Zilbrysq was successful. You can read more about our appeal here.

In 2025, we successfully appealed NICE’s original decision not to approve Zilbrysq for NHS use in England. Since the appeal, the NICE committee met again to discuss the available evidence. NICE is now asking for feedback to help inform their final decision. They will meet again in the coming months to make this decision.

We will be submitting comments alongside myaware to the latest round of feedback. We are particularly interested in hearing from people with experience of plasma exchange (PLEX). NICE is comparing zilucoplan with treatments already used for myasthenia gravis, including PLEX, and we want to ensure the realities of receiving this treatment are properly understood.

If you have myasthenia gravis and have experience of PLEX, please complete our survey

We are also keen to hear from people who have experience of zilucoplan. We want to understand the difference the treatment has made to your condition, particularly whether it has reduced exacerbations or myasthenic crises compared with previous treatments such as IVIg or PLEX.

If you would like to share your experience of zilucoplan, please contact campaigns@musculardystrophyuk.org.

Anyone can also submit comments directly to NICE before the consultation closes on 28 August. Details of how to respond can be found on the NICE website.

We are working in partnership with the charity myaware to make sure the experience and views of the myasthenia gravis community are heard throughout the NICE assessment process.

This has included:

• nominating and supporting two members of the community to share their experience of myasthenia gravis and Zilbrysq
• providing feedback on the draft guidance

Zilbrysq was tested in the phase 3 RAISE trial. 174 participants, aged between 18 – 74 years old, with a myasthenia gravis activities of daily living (MG-ADL) score of at least six took part in the trial. The MG-ADL score measures the impact of the condition on a person’s daily function, such as talking, swallowing and getting up from a chair. The score can range from zero to 24, with a lower score means symptoms are less severe.

Participants were randomly assigned to receive Zilbrysq (86 participants) or placebo (dummy drug, 88 participants). All participants tested positive for the antibodies which attack acetylcholine receptors. Zilbrysq was found to be safe. After 12 weeks, more participants who received Zilbrysq showed improvements in the MG-ADL scale, compared to those who received the placebo.

73% of participants who received Zilbrysq had a reduction of at least three points, compared to 46% of participants who received the placebo. A reduction of two points is considered to be beneficial (clinically meaningful) to people living with the condition. This may mean people with the condition are able to complete daily tasks they were unable to before, such as brush their hair or get up out of a chair without assistance.

Long-term data is being collected in the RAISE-XT trial.

Last updated: 10/08/2026