Siponimod (Mayzent)

Siponimod is a disease modifying therapy (DMT) used to treat active secondary progressive multiple sclerosis (SPMS).

DMTs are treatments for people with multiple sclerosis (MS) that can help change the course of your MS by reducing the number of relapses and slowing down the buildup of disability in the long term.

You take siponimod as a tablet once a day. It reduces the number of relapses you may have by 55% and slows down disability progression.

Siponimod is marketed under the brand name Mayzent.

On this page we cover who can take siponimod, how it works, its benefits and possible side effects.

Siponimod is used for treating adults with active secondary progressive multiple sclerosis (SPMS). This means you’re experiencing relapses and/or you have new, active or enlarging lesions on an MRI scan.

If you have relapsing remitting MS (RRMS), siponimod may be an option for you if your symptoms are progressing despite being on a disease modifying therapy (DMT) and the progression is not being caused by relapses.

Your MS team will assess whether siponimod is suitable for you and whether you meet the NHS criteria for treatment (NHS England).

Siponimod can only be prescribed by a neurologist.

White blood cells are part of your immune response and help fight infections. In MS, these immune cells mistakenly attack the protective covering around your nerves (myelin) in your brain and spinal cord (central nervous system).

Siponimod works by attaching itself to the surface of white blood cells. These cells, called lymphocytes, then become trapped in the lymph glands. This stops them from crossing into your central nervous system and causing inflammation and damage.

Because siponimod lowers the number of white blood cells that can circulate in your blood, people taking siponimod have a higher risk of infections.

In clinical trials, siponimod has been shown to reduce relapses by 55% when compared to a placebo (dummy medicine). It also slowed down disability progression by 37% compared to placebo.

We have more information on how medicines are developed.

Before you start taking siponimod, your MS team will discuss the benefits and possible risks of the therapy with you. Together, you will decide if the benefits outweigh any potential risks based on your circumstances. We have more information about starting a disease modifying therapy (DMT) and things to consider.

It's important that you tell your MS team if you have any health problems or are taking other medicines.

Siponimod may not be recommended for you if:

• you are allergic to peanut, soy or any of the ingredients in the medicine
• you have a weakened immune system
• you have had a serious brain infection in the past, for example progressive multifocal leukoencephalopathy (PML)
• you have active cancer
• you have severe liver problems
• you have, or have had, serious heart problems, for example a heart attack, an irregular or abnormal heartbeat, stroke or heart failure
• your body cannot break down the medicine well enough (this will be tested before starting treatment).

You may need additional tests before starting siponimod and extra monitoring during treatment if:

• you have, or have had, a condition affecting your eyes – for example, swelling at the back of the eye (macular oedema (Macular Society)) or an infection or inflammation of the eye (uveitis (NHS.UK))
• you have diabetes
• you have ever had any heart problems
• you have severe breathing problems when sleeping (sleep apnoea)
• you have high blood pressure
• you have ever had liver problems.

If you're considering treatment with siponimod or any other disease modifying therapy (DMT), your MS team will proactively discuss family planning and the possibility of pregnancy with you where appropriate.

Siponimod should not be taken when trying for a baby or during pregnancy as there is a risk it could harm your unborn baby. You should therefore use contraception when taking siponimod.

If you're planning to become pregnant, your MS team will discuss stopping or switching to a different DMT before you start trying for a baby. Siponimod should be stopped at least 10 days before you start trying to conceive.

Siponimod should not be taken while breastfeeding as it can pass into breastmilk and may cause side effects for your baby.

Before starting siponimod, you will have tests to determine if it is suitable for you. These include:

• a blood or saliva test to check how quickly your body breaks down siponimod and to work out the best dose for you
• a full blood count (NHS.UK)
• liver blood tests (Liver UK) to check your liver function
• blood test to check kidney function
• a skin examination
• a pregnancy test, where appropriate
• a blood test to check your immunity against the virus that causes chickenpox
• tests to check you do not have hepatitis B, hepatitis C, human immunodeficiency virus (HIV) or tuberculosis
• an MRI scan
• an electrocardiogram (ECG) (NHS.UK) if you have a heart condition
• an eye examination if you have a condition that affects your eyes.

In a small number of cases, the test that checks how quickly your body breaks down siponimod may show that this therapy is not suitable for you.

If a blood test shows that you're not protected against chickenpox, measles, mumps or rubella, you may need to have these vaccinations at least 1 month before starting siponimod. This is because live vaccines cannot be given once treatment has started.

You take siponimod as a tablet once a day.

To give your body time to get used to the drug and reduce the risk of side effects, you start on a low dose which is gradually increased over 5 days. From day 6 you take the full dose.

It is recommended that you take siponimod in the morning with or without food.

When you first start taking siponimod, it may temporarily cause your heart rate to slow down or become irregular. This may make you feel dizzy or lightheaded so you should not drive or use machinery on your first day of treatment. Your heart rate should return to normal within 10 days.

You should not stop taking siponimod without discussing your ongoing treatment with your neurologist, as your MS may become more active after stopping this therapy.

Siponimod stays in the body for up to 10 days after you stop taking it, so you may continue to experience side effects during this time.

All medicines, including disease modifying therapies (DMTs), can potentially cause side effects.

Some people may not experience side effects from taking siponimod. Some may find that any side effects ease after the first month or two as their body adapts to the medicine. For others, side effects may persist.

Your MS team will discuss potential side effects of the treatment with you and help you understand your risk. They will also tell you how to manage and report any side effects. If you do experience side effects, it’s important to discuss them with your MS team.

Very common side effects (may affect more than 1 in 10 people) of siponimod include:

• headache
• high blood pressure
• increased liver enzymes (this can be a sign of liver damage).

Common side effects (may affect up to 1 in 10 people) of siponimod include:

• shingles (herpes zoster) (NHS.UK) – symptoms include a rash with small fluid-filled blisters (the rash may look red on light skin tones and purplish, dark pink, dark brown or grey on black or brown skin)
• a type of skin cancer called basal cell carcinoma (NHS.UK) – signs include a pearly nodule (shiny, dome-shaped bump) on the skin
• low levels of white blood cells (lymphopenia) which may make you more vulnerable to infections
• changes in your vision – for example a shadow or blind spot in the centre of your vision, blurred vision or problems seeing colours or details (signs of macular oedema (Macular Society))
• changes to your heart rate
• seizures
• swollen hands, ankles, legs or feet.

If you notice any changes to your eyesight whilst on treatment with siponimod, speak to your MS team or GP.

Basal cell carcinoma is a slow-growing skin cancer that almost never spreads to other parts of the body or becomes life-threatening but can be disfiguring if not treated promptly. You should check your skin regularly and talk to your GP or MS team straightaway if you notice any changes. As siponimod may increase your risk of this type of skin cancer, you should limit your exposure to the sun and UV rays by wearing protective clothing and regularly applying a high factor suncream.

Siponimod may also increase your risk of other types of skin cancer (squamous cell carcinoma (NHS.UK) and malignant melanoma (NHS.UK)), but this is uncommon.

Cases of a serious brain infection called progressive multifocal leukoencephalopathy (PML) have been reported in people taking siponimod, however this is rare. When you start taking siponimod you will be informed of the early signs of PML. Symptoms of PML can be similar to an MS relapse. If you notice any new or worsening symptoms, you should report them to your MS team straightaway.

For a full list of side effects, see the Patient Information Leaflet for siponimod (Mayzent).

• Patient Information Leaflet for Mayzent (EMC)

You can report side effects through the Yellow Card scheme. Reporting side effects can make a big difference to other people using the same medicine as you.

People with MS are generally encouraged to have vaccinations which are part of the national vaccinations programme (NHS.UK). Where possible, your MS team will advise you to get relevant vaccinations before you start taking a disease modifying therapy (DMT).

If you've not started treatment with siponimod yet, it's recommended that inactivated (non-live) vaccines are given at least 2 weeks before treatment starts. Live vaccines should be given at least 4 weeks before starting siponimod. This is to make sure your immune system builds up a good response to the vaccines.

If you're already on siponimod, inactivated (non-live) vaccines (such as the flu jab) are considered safe for you to have. Your body’s response to vaccines may be slightly reduced but they still provide some protection.

Live vaccines are not recommended for people on siponimod. This is because there is a small potential risk of developing vaccine-related infections.

Once you've started treatment, you'll have regular blood tests to monitor your liver function and measure blood cell counts. Your blood cell counts should be checked 3 to 4 months after starting siponimod, and then at regular intervals. This will be at least once a year, but is often done more frequently.

Your blood pressure should be checked regularly. You should have skin examinations every 6 to 12 months.

If you have a history of heart problems, your MS team may monitor you more closely when you first start taking siponimod.

About 3 to 4 months after starting siponimod, you should have an eye test to check for macular oedema. If you have a pre-existing health condition which affects the eye, such as diabetes, you may have more frequent eye examinations during treatment.

You will likely have regular MRI scans to check your disease modifying therapy (DMT) is working effectively. Your neurologist will advise how often you should have one. They may recommend having an MRI scan 3 to 6 months after starting treatment, then once a year after this to check for MS activity. However, the frequency can vary between MS teams and MRI scans may be done less often than this.

• Patient Information Leaflet – Mayzent (EMC)

This information has been developed by the MS Trust Health Information team. Our team produces accurate evidence-based information to help you navigate your every day – working alongside health professionals. We would like to thank the following health professionals for checking the clinical accuracy of this information:

• Brina Bharkhada, Principal Pharmacist, University College London Hospitals NHS Foundation Trust
• Hollie Bamford, MS Nurse Specialist, East Suffolk and North Essex NHS Foundation Trust
• Victoria Wallace, Consultant Neurologist, Kingston and Richmond NHS Foundation Trust.