Tag Archives: licence

Detail, DMTsDetail, Treatment strategy

What are the attributes of the specific DMTs?

Multiple sclerosis (MS) treatment has evolved rapidly, with 11 classes of disease-modifying therapy (DMT) now available in the UK. I will summarise them briefly and explain how they fit within a treatment paradigm for effective and safe use.

Maintenance therapies versus immune reconstitution: what’s the difference?

There is a divide between the two main treatment philosophies: maintenance ̶ escalation versus immune reconstitution therapies (IRTs).

An IRT is given as a short course – a one-off treatment in the case of autologous haematopoietic stem cell transplantation (AHSCT) or intermittently for alemtuzumab, cladribine or mitoxantrone. IRTs are not given continuously, and additional courses are given only if inflammatory activity recurs. IRTs can induce long-term remission and, in some cases, potentially a cure.

Maintenance therapies, by comparison, are given continuously without an interruption in dosing (‘continuous’ administration may be daily, one or more times weekly, monthly or even once every few months). Although maintenance therapies can induce long-term remission, they cannot, by definition, result in a cure. The recurrence or continuation of inflammatory activity indicates a suboptimal response to treatment and typically requires a treatment switch. Ideally, this switch should be an escalation to a more effective class of DMT.

An article in our list of key questions, entitled How do I want my MS to be treated?, provides a more detailed comparison of maintenance and IRT therapies, including frequency of administration, efficacy, risks, use in pregnancy, vaccine response and potential for a cure.

The DMTs currently licensed in the UK (in August 2024) are listed in the table under the relevant category.

table format updated 180625 SS

Disease-modifying therapies for MS licensed in the UK. *Please note, Bonspri is available in other markets but not the UK.

How effective are the different DMTs?

The measures used to assess the effectiveness of a DMT include its ability to reduce or prevent relapses, focal inflammatory activity (that is, new or enlarging lesions) on magnetic resonance imaging (MRI), and disability progression. Additional factors that can help to assess the relative efficacy of DMTs include the proportion of clinical trial subjects who experience improvement in disability and the impact of the treatment on brain volume loss.

The MS-Selfie InfoCards are an easy-to-use resource to help people with MS compare the key features of each DMT. They contain bite-sized information designed to aid treatment choices and an overview of the key aspects of each DMT.

Efficacy of the licensed DMTs for MS can be visualised as pyramid, with the moderately effective treatments at the bottom and the more effective approaches at the top. What determines the most appropriate DMT efficacy level for an individual depends on several factors, such as baseline prognostic profile, family planning requirements, local or national treatment guidelines, socioeconomic factors, consideration of any co-existing illnesses, cognitive impairment, risk aversion and lifestyle issues.

Pyramid format updated 180625 SS

UK licensed DMTs for MS, in ascending order of efficacy.
HSCT/AHSCT, haematopoietic stem cell transplantation/autologous haematopoietic stem cell transplantation.

What is the goal of treatment? Introducing NEIDA as a target

In the past, we used no evident disease activity (NEDA) as a treatment target. ‘Disease activity’ included progression or disease worsening independent of relapse activity (termed smouldering MS). Although some of the more effective DMTs may modify this stage of the disease, many neurologists feel uncomfortable switching or stopping a DMT based simply on smouldering MS disease activity. 

Relapses and ongoing focal MRI activity are associated with a worse short-term to intermediate-term prognosis. These observations have led to the increasing adoption of ‘no evident inflammatory disease activity’ (NEIDA) as a new treatment target. For more information about treatment targets, please see the article in our key questions, Do I understand the concepts of treat-2-target and NEDA?

Many healthcare professionals (HCPs) remain sceptical of using NEIDA as a treatment target, fearing that this could lead to more people with MS being on ‘riskier’ high-efficacy therapies. However, achieving long-term remission, or NEIDA, is a well-established treatment target in other autoimmune diseases such as rheumatoid arthritis and inflammatory bowel disease. People with MS treated-to-target of NEIDA from the outset do better than those whose treatment is escalated following breakthrough disease (at a clinical or subclinical/MRI level)1. I would, therefore, strongly encourage people with MS and their HCPs to adopt NEIDA as an initial treatment target.

Flipping the pyramid

The effectiveness, or relative effectiveness, of individual DMTs becomes less critical in the context of a treatment target of NEIDA. Choosing a DMT with a lower efficacy rate simply means that a greater proportion of treated people with MS will need to be switched to higher efficacy therapies over time to achieve NEIDA. We refer to the latter of these three approaches – starting with high-efficacy treatment – as flipping the pyramid. In recent trials of alemtuzumab, ocrelizumab, ofatumumab and ublituximab, people with MS randomised to 2 years of lower efficacy DMTs (interferon-beta-1a or teriflunomide) had poorer outcomes than those receiving highly active therapy from the outset. Real-world data from registries also support this; groups of people with MS with delayed access to high-efficacy DMTs did worse than those who received high-efficacy treatments early.1,2

Horizontal versus vertical switching

If we consider the conventional step care paradigm, people with MS who switch horizontally from interferon-beta to glatiramer acetate, or vice-versa (i.e. from one moderate efficacy DMT to another moderate efficacy DMT) do less well than those who switch vertically to fingolimod, a highly effective DMT. Similarly, people with MS escalating to natalizumab, a very high-efficacy DMT, do better than those being escalated to the less effective, but still high-efficacy, DMT fingolimod. 

Continuous and intermittent immunosuppression

Another useful way of classifying DMTs is whether they are immunosuppressive, that is, they reduce the activation, or effectiveness, of the immune system. Drug regulators stipulate that a drug may be classified as immunosuppressive if it (1) causes significant lymphopaenia (low lymphocyte count) or leukopenia (low white blood cell count), (2) is associated with opportunistic infections, (3) reduces the antibody and immune response to vaccines and (4) increases the risk of secondary malignancies.

The duration and intensity of immunosuppression further determine the risks. For example, short-term or intermittent immunosuppression associated with IRTs front-loads the risks, which are substantially lower once the immune system has reconstituted itself. In comparison, long-term continuous or persistent immunosuppression, which occurs with some of the maintenance DMTs, accumulates problems over time, particularly opportunistic infections and secondary malignancies. You can read more detail on this topic in the key question How immunosuppressed am I? The following table summarises the main attributes of intermittent and persistent immunosuppression.

How immunosuppressed are you table updated format 180625 SS

The main characteristics of continuous (persistent) and short-term (intermittent) immunosuppression. Modified from Giovannoni, Curr Opin Neurol.2
AHSCT, autologous haematopoietic stem cell transplantation; PML, progressive multifocal leukoencephalopathy.

Adverse effects, monitoring and risk reduction

The complications associated with immunosuppression vary from DMT to DMT. Each individual drug summary in the DMTs section of MS-Selfie contains detailed information about the main adverse events, key monitoring requirements, use (or contraindication) during pregnancy and breastfeeding, and response to vaccines. The MS-Selfie InfoCards provide bite-sized summaries of several practical aspects, including side effects, to enable easy comparison of any treatments you are considering; some of this information is collated below for easy reference.

Short-term versus long-term adverse effects

Each drug has been given scores from 1 to 10 based on published analyses of its short-term and long-term side effects. Short-term refers to side effects that emerge when a treatment is started and decrease in severity or disappear within days or weeks. A well-known example of short-term side effects on starting interferon-beta is flu-like symptoms that typically abate within 4 ̶ 8 weeks.

A long-term side effect persists for months or doesn’t disappear on continuing the DMT. Examples include intermittent but persistent flushing after taking dimethyl fumarate, or low B lymphocyte counts with anti-CD20 therapies that may lead to low antibody or immunoglobulin levels (hypogammaglobulinaemia).

A low score denotes few or rare side effects; a high score denotes many or frequent side effects. The score does not correlate to a percentage. More information can be found in each drug summary and the manufacturer’s Summary of Product Characteristics.

Scores for short-term and long-term side effects assigned to the individual DMTs summarised in the MS-Selfie InfoCards, based on a published network meta-analysis.3
Alem, alemtuzumab; GA, glatiramer acetate; HSCT, haematopoietic stem cell transplantation; IFN-beta; interferon-beta; Nat, natalizumab.

Monitoring and risk reduction

Numerous tests are carried out at the start of treatment, and ongoing monitoring is required for many factors, to reduce the risk from adverse events. The key question, How can I reduce my chances of adverse events on specific DMTs?, explains what needs to be done at the start of DMT administration (baseline) and during subsequent monitoring. The specifics vary from DMT to DMT; please refer to the individual summaries for details such as baseline tests, follow-up, infection prevention, cancer risk, pregnancy, breastfeeding and vaccination. It is important to remember that all licensed MS DMTs have had a thorough risk ̶ benefit assessment, and their benefits are considered to outweigh the potential risks.

Administration and other practical considerations

Routes and frequency of administration

The MS-Selfie InfoCards contain a symbol for each DMT, showing how it is administered. Some DMTs are available in more than one formulation (e.g. tablets and injection). The frequency of administration varies greatly from DMT to DMT; please consult the relevant summary in the DMTs section and discuss your preferences and priorities with your MS HCP.

The route of administration for each drug in the MS-Selfie InfoCards is clearly identified by the relevant symbol. (If a DMT is available in more than one formulation, there is a separate card for each delivery route.)

Number of clinic visits

It may be important for you to consider the frequency of clinic visits. This will depend on factors such as the delivery route of your DMT, the monitoring requirements of the drug regulators and the risk of specific side effects. The table below summarises the assessments from the MS-Selfie InfoCards. This is another factor to consider in discussions with your MS HCPs about the most appropriate DMT for you.

Conclusions

People with MS must understand the objectives of MS treatments and the different treatment strategies currently available to achieve these objectives. Although the MS therapeutic landscape is complex and hence may seem overwhelming, framing the choices using a relatively simple construct should help each individual to make informed decisions about managing their MS. MS-Selfie aims to guide you in the process of deciding on the most appropriate therapeutic strategy and specific DMT for treating your disease.

References

  1. Rotstein D, et al. Association of No Evidence of Disease Activity with no long-term disability progression in multiple sclerosis: a systematic review and meta-analysis. Neurology 2022;99:e209̶ ̶ 20.
  2. Giovannoni G. Disease-modifying treatments for early and advanced multiple sclerosis: a new treatment paradigm. Curr Opin Neurol 2018;31:233 ̶ 43.
  3. Samjoo IA, et al. Efficacy classification of modern therapies in multiple sclerosis. J Comp Eff Res 2021;10:495–507.
Pregnancy and childbirth, Women's health

Breastfeeding if you are on a DMT

This section explains how relapse is managed during breastfeeding and provides detailed guidance on which DMTs are safe (or not safe) to use while breastfeeding.

Will I be able to breastfeed after delivery?

Yes, I see no reason why you can’t breastfeed if you have MS. However, certain DMTs cross over into the breast milk and may affect the baby; these include teriflunomide, cladribine and S1P modulators (fingolimod, siponimod, ozanimod and ponesimod). Although monoclonal antibodies (natalizumab, ocrelizumab, ofatumumab, rituximab) cross over in small amounts, the levels are generally too low to affect the newborn. In addition, the level of the antibodies will likely be further reduced by their digestion as proteins in the baby’s intestinal tract.

Please be aware that most DMTs are licensed with no breastfeeding safety data. Hence, the information in the manufacturer’s Summary of Product Characteristics (SmPC) is not the same as that given to you by neurologists and other HCPs. For example, SmPC information for the fumarates (dimethyl fumarate and diroximel fumarate) states:

“It is unknown whether dimethyl fumarate or its metabolites are excreted in human milk. A risk to the newborns/infants cannot be excluded. A decision must be made whether to discontinue breastfeeding or to discontinue Tecfidera therapy. The benefit of breastfeeding for the child and the benefit of therapy for the woman should be taken into account.”

This is very unhelpful as their active compound, monomethyl fumarate, is a naturally occurring metabolite compounded with many other medications considered safe in pregnancy, e.g. ferrous fumarate, an iron supplement. This is why I tell my female patients on fumarates they can breastfeed without concern for their baby.

We normally don’t recommend alemtuzumab treatment during breastfeeding simply because it carries the risk of listeriosis and infusion reactions, and the medications used to prevent these adverse events cross over into breast milk. In addition, the acute immunosuppression associated with alemtuzumab may increase the risk of breast infections. In general, I advise my female patients to breastfeed for 4 ̶ 6 weeks to give the baby the health benefits of breastfeeding and then to start or be retreated with alemtuzumab after this period.

For cladribine, it is important not to breastfeed whilst being dosed with the drug and for 10 days after the last pill. The recommended 10-day requirement is probably a bit long as cladribine is undetectable in the body after 48 ̶ 72 hours. In my experience, the requirement of a 14- or 15-day gap (4 or 5 days of dosing plus an additional 10 days) in breastfeeding is hard; therefore, most women who want to be treated with cladribine either delay treatment until they have completed breastfeeding or breastfeed for 4 ̶ 6 weeks before stopping and being treated with cladribine.

Breastfeeding

Guidance for women who are considering whether it is safe to breastfeed while taking a specific DMT.

I am aware that many women feel pressured into breastfeeding. However, if you are anxious about having MS rebound post-partum, deciding not to breastfeed and starting or resuming your DMT as soon as possible is not unreasonable. The decision is a personal choice.

How is a relapse managed during breastfeeding?

In the event of a relapse during breastfeeding, a short course of high-dose corticosteroids can be considered. Methylprednisolone – the steroid often used to manage MS relapses – is transferred into breast milk. However, the amount an infant is exposed via breast milk is low (equivalent to less than 1% of the adult dose). Some clinicians recommend women breastfeed before a steroid infusion, express breast milk 1 ̶ 2 hours after the infusion and discard it, to limit the baby’s exposure to methylprednisolone. I don’t think this is necessary.

References

Krysko KM et al. Treatment of women with multiple sclerosis planning pregnancy. Curr Treat Options Neurol 2021;23:11.

Other articles in this series on Pregnancy and childbirth
Planning for pregnancy
Managing MS during pregnancy
Preparing to give birth
Concerns about parenting

DMTsSafety, Monitoring MS

How can I reduce my chances of adverse events on specific DMTs?

The complications associated with immunosuppression vary from DMT to DMT. You will find it helpful to understand what investigations to expect before and during treatment and how these may vary depending on the DMT(s) you are considering.

Key points

  • Numerous tests are carried out at the start of your treatment (baseline); these include blood, urine and tests for a range of infections.
  • Some patients will need tests or procedures specific to their DMT that are inappropriate for everyone with MS – for example, vaccination against some infections; pregnancy and/or genetic counselling; prevention of cardiovascular complications; and management of infusion reactions.
  • Ongoing monitoring is required for many but not all of the above factors.
  • All licensed MS DMTs have had a thorough risk ̶ benefit assessment, and their benefits are considered to outweigh the potential risks.

Standard tests … and why we do them

If you have read the article on immunosuppression, you will know that immunosuppressive DMTs may reduce white blood cell counts and antibody responses to vaccines and increase the likelihood of some infections and cancers. However, we can reduce the risk of many complications associated with long-term immunosuppression (we use the shorthand ‘de-risk’). This article explains what needs to be done at the start of DMT administration (baseline) and during subsequent monitoring. The specifics, however, vary from DMT to DMT.

Baseline tests

Tests at baseline (before starting DMT administration) include full blood count, platelets, liver, kidney and thyroid function tests, and a urine screen. Recording baseline immunoglobulin levels is particularly important if you are about to start an anti-CD20 therapy (ocrelizumab, ofatumumab or rituximab) so that we have a reference level for future comparisons. 

Serum protein electrophoresis is done for patients considering starting interferon-beta; having a so-called monoclonal gammopathy (an abnormal immunoglobulin) is a contraindication to starting an interferon-beta formulation in people with MS. The drug has been associated with a form of capillary leak syndrome, leading in rare cases to death from an adult respiratory distress syndrome.

The table below summarises the routine investigations required at baseline; subsequent sections provide further detail.

Tests routinely carried out at the start of treatment (baseline).
AHSCT, autologous haematopoietic stem cell transplantation; CMV, cytomegalovirus; CSF, cerebrospinal fluid; DMT, disease-modifying therapy; EBV, Epstein ̶ Barr virus; ECG, electrocardiogram; FBC, full blood count; HIV, human immunodeficiency virus; HPV, human papillomavirus; JCV, JC virus; LFTs, liver function tests; MMR, measles/mumps/rubella; MRI, magnetic resonance imaging; PCP, pneumocystis pneumonia; PML, progressive multifocal leukoencephalopathy; TB ELISpot, tuberculosis enzyme-linked immune absorbent spot; TFTs, thyroid function tests; U&E, urea and electrolytes; VZV, varicella zoster virus.

Infection screening

At our centre, we screen for a relatively large number of infectious diseases so that we can treat any subclinical infection before starting a DMT. This is particularly relevant for HIV-1 and 2, hepatitis B and C, syphilis and tuberculosis (TB).  

Screening for the JC virus (JCV), which causes progressive multifocal leukoencephalopathy (PML), is only really needed for people with MS considering starting natalizumab. Even if you are JCV positive, you can be treated with natalizumab for 6 ̶ 12 months and sometimes longer if you are prepared to take on the risk of PML and the extra monitoring required to detect PML early. 

We only check measles/mumps/rubella (MMR) status in patients without documentation of full vaccination as children. We check varicella zoster virus (VZV) status before starting immunosuppression and vaccinate seronegative individuals. Currently, we are still using the live VZV vaccine. This will change, and we will likely be offering all people with MS in the UK the component inactive VZV vaccine (Shingrix, that has had its licence extended) to reduce the chances of zoster reactivation in all adults starting immunosuppression. This new Shingrix indication is similar to the pneumococcal vaccine (Pneumovax). Our centre is only recommending Pneumovax in patients about to start an anti-CD20. However, when Shingrix becomes available on the NHS, it will make sense to bundle this with the Pneumovax and make it routine for all people with MS before starting immunosuppressive therapy. Please check with your healthcare team which products are available locally.

Routine tests and monitoring for Epstein-Barr virus (EBV) and cytomegalovirus (CMV) are only needed for subjects undergoing autologous haematopoietic stem cell transplantation (AHSCT), which causes profound short-term immunosuppression that can result in CMV and EBV reactivation. CMV reactivation also occurs with alemtuzumab, so this needs to be considered when investigating patients who develop complications after receiving alemtuzumab (please see Opportunistic infection in MS). 

For patients starting long-term immunosuppression, it is advisable to screen for active human papillomavirus (HPV) infection (by cervical smear or vaginal swab) and for warts or active infection with molluscum contagiosum. Warts are caused by HPV skin infection; molluscum contagiosum is due to a relatively benign pox virus that typically affects young children but occasionally affects adults. Warts and molluscum contagiosum can spread rapidly in patients receiving alemtuzumab, so I recommend treating these skin infections before starting immunosuppression for MS. 

Vaccinations

We encourage all patients to be vaccinated against COVID-19 and seasonal flu; outside the flu vaccine season, we remind people to get vaccinated during the next vaccine season. 

Hepatitis B, meningococcal and Haemophilus influenzae vaccines are considered only for people with MS who are at high risk of infection and have not had these vaccines as part of a national vaccine programme, i.e. healthcare and laboratory workers for hepatitis B, school and university students and military recruits for meningococcal vaccine and paediatric patients for Haemophilus influenzae. 

The issue around having the HPV vaccine as an adult is more complex. For example, in the UK, the NHS does not cover the cost of the vaccine for people over 25. In addition, most people have only had the quadrivalent vaccine (Gardasil-4), which covers about two-thirds of the strains that cause cancer. Some people with MS may want to upgrade their immunity with the polyvalent vaccine (Gardasil-9) that covers over 95% of the cancer-causing strains of HPV. For more information on HPV vaccination, please see Case study: cervical intraepithelial neoplasia (CIN) and ocrelizumab.

MMR is a live vaccine given in childhood (see MMR vaccine: to vaccinate or not? ). Owing to vaccine hesitancy, however, many people do not receive this vaccine as children. Therefore, if an adult with MS is about to start immunosuppressive therapy and has not been vaccinated against MMR, we advise them to do so. This is particularly important for people about to start natalizumab because these viruses are neurotropic and can infect the brain. Natalizumab blocks immune response within the brain; hence, exposure to a neurotropic virus could cause serious infection, similar to what we see with the JC virus – which causes PML.

Travel vaccines for people who travel as part of their work or plan to travel shortly need to be considered. In particular, the yellow fever vaccine is a live vaccine (made from a weakened yellow fever virus strain) and it should ideally be given before someone starts on immunosuppressive therapy. 

Cardiovascular screening

You may need an ECG (electrocardiogram), to rule out an abnormal heart rhythm or electrical conduction abnormality and to check your left ventricular function (ejection fraction). These abnormalities are a relative contraindication to using the S1P modulators (fingolimod, siponimod, ozanimod, ponesimod), which may affect the conduction of the heart. In patients treated with mitoxantrone, the left ventricular ejection fraction (LVEF) must be done at baseline and regularly monitored because mitoxantrone is toxic to the heart. If the LVEF drops significantly, further dosing of mitoxantrone is contraindicated. 

Pregnancy, family planning and genetic testing

Many chemotherapy agents used in AHSCT for ablating (extracting) the bone marrow are toxic to the ovaries and testes. Therefore, patients receive counselling before treatment and can have eggs (oocytes) or sperm banked for future use. Egg banking is also a consideration for women with MS being treated with mitoxantrone. Men receiving mitoxantrone do not need to bank sperm, however, because mitoxantrone does not cross the testes ̶ blood barrier. 

Genetic testing is only required at present if you wish to receive siponimod. Siponimod is metabolised by a specific liver enzyme (biological catalyst) with two functional variants – slow metabolising and fast metabolising. People who carry two slow-metabolising variants of the enzyme cannot receive siponimod. Intermediate metabolisers (those that carry one slow- and one fast-metabolising version of the enzyme) receive low-dose siponimod, while those with two fast-metabolising enzymes receive high-dose siponimod. 

Protecting against progressive multifocal leukoencephalopathy

I have included magnetic resonance imaging (MRI) and lumbar puncture with cerebrospinal fluid (CSF) testing for JCV among the baseline tests. This is specific to patients at high risk of developing PML who are switching from natalizumab to a depleting immune reconstitution therapy such as alemtuzumab or another therapy that depletes their immune system (e.g. cladribine or an anti-CD20 therapy). These tests are done to exclude asymptomatic PML, which will otherwise be carried over to the new treatment. The effects of these immunosuppressive therapies on your immune system cannot be rapidly reversed, which is a problem because immune reconstitution is needed to clear PML. Most MS centres do not mandate CSF testing in this situation because it does not always reveal the presence of PML. However, I still request this test on my patients to gain as much information as possible on which to base potentially life-changing decisions.

Prophylactic antivirals and antibiotics

Patients in our centre undergoing AHSCT or receiving alemtuzumab will be given antivirals and antibiotics to reduce the likelihood of certain infections. This is particularly relevant for listeriosis, which is a rare infection transmitted via food. We also encourage all our patients to start and maintain a specific diet to reduce the chances of listeriosis. The risk of listeriosis is only present for a short period when both the adaptive and innate immune systems are compromised, that is, for 4 weeks after receiving alemtuzumab, so we recommend antibiotic prophylaxis for 4 weeks. Our online resource provides more information about listeriosis. If you live in the UK, you can order our free listeriosis prevention kit, which contains a booklet (also downloadable) and various practical items to help keep you safe.

Strategies for limiting the risks from immune reconstitution therapies and infusion DMTs.

Infusion reactions

When you use agents that cause cell lysis (breakdown), such as alemtuzumab and intravenous anti-CD20 therapies, the contents of cells cause infusion reactions. To prevent such reactions or reduce their severity, we pretreat patients with corticosteroids, antihistamines and antipyretics. The exact protocols for each DMT differ; for example, ocrelizumab infusion reactions are generally only a problem with the first and second doses; therefore, many centres don’t give steroids with the third and subsequent infusions. The latter was particularly important during the COVID-19 pandemic when it was shown that the recent administration of high-dose steroids increased your chances of severe COVID-19. 

Ongoing monitoring

Once someone has been treated with a DMT, ongoing monitoring is required. What gets monitored and how frequently depends on the individual DMT. For a list of DMTs associated with important adverse events, please see our summary Table in ‘De-risking’ guide: monitoring requirements of individual DMTs.

The regulatory authorities usually put in place specific monitoring requirements, which can differ worldwide. It is important that you also enrol in your national cancer screening programmes. Being on chronic immunosuppression increases your chances of developing secondary malignancies, so please remain vigilant. 

Tests carried out regularly as part of ongoing monitoring.
FBC, full blood count; LFTs, liver function tests; MRI, magnetic resonance imaging; PML, progressive multifocal leukoencephalopathy; TFTs, thyroid function tests; U&E, urea and electrolytes.

I want to reassure you that all licensed MS DMTs have undergone a thorough risk ̶ benefit assessment by the drug regulators, and the benefits of these treatments are considered to outweigh the potential risks. On balance, the level of immunosuppression associated with MS DMTs is typically mild to moderate; hence, the complications are relatively uncommon. MS is a serious disease and, if left to run its natural course, would result in most patients becoming disabled. To learn more about the natural course of MS, please read the section entitled What are the consequences of not treating MS?

DMTsSafety, Monitoring MS

‘De-risking’ guide: monitoring requirements of individual DMTs

Before you start taking a disease-modifying therapy (DMT), your MS team will carry out routine tests and investigations, many of which are repeated during subsequent monitoring or before switching to another DMT. The regulatory authorities that license the drugs specify their monitoring requirements. What gets monitored and how frequently depends on the individual DMT.

All licensed MS DMTs have undergone a thorough risk ̶ benefit assessment by the drug regulators, and the benefits of these treatments are considered to outweigh the potential risks. The table below summarises the main monitoring requirements of individual DMTs or DMT classes. For more detailed information, see the post on reducing your chances of adverse events.

AHSCT, autologous haematopoietic stem cell transplantation; CMV, cytomegalovirus; CSF, cerebrospinal fluid; EBV, Epstein ̶ Barr virus; ECG, electrocardiogram; HPV, human papillomavirus; JCV, JC virus; LVEF, left ventricular ejection fraction; MRI, magnetic resonance imaging; PML, progressive multifocal leukoencephalopathy.

DMTs, Treatment strategy

Am I eligible for an MS disease-modifying therapy?

Key points

Do you know the eligibility criteria for MS disease-modifying therapies? And who decides what drugs can be prescribed for your MS?

  • Disease-modifying treatments (DMTs) change the long-term trajectory of MS and protect the central nervous system from further damage.
  • Regulators such as the European Medicines Agency (EMA) and the Federal Drug Administration (FDA) decide in which group(s) of patients a particular drug can be used, based on the results of clinical trials.
  • Once a drug has been licensed in your region, local payers decide whether to make it available within your country, based on cost-effective assessments.
  • If you have active MS, your level of disease activity, its severity and speed of development will determine which DMTs you can be offered.
  • In some countries, ocrelizumab has been approved for the treatment of active primary progressive MS (PPMS) and siponimod has been approved for the treatment of active secondary progressive MS.
  • Protecting upper limb function has been a neglected area; studies are now ongoing, however, with a view to finding DMTs that limit the progression of upper limb disability.

What do disease-modifying drugs do?

Disease-modifying therapies (DMTs) are treatments that change the natural history – that is, the long-term trajectory – of the disease. They reduce the rate of disability worsening and so protect the end-organ (in the case of MS, this is the central nervous system). To simplify, let’s say that a person with MS on no treatment may manage for an average of 18-20 years before needing to use a walking stick (corresponding to Expanded Disability Status Scale [EDSS] 6.0), while someone on treatment might manage without aid for 24 years, i.e. a 4-6-year delay, then the treatment can be called disease-modifying. (Please note, the treatment effect or 4-6-year delay in reaching EDSS 6.0 is an average and some people with MS will do better than others. Conversely, some will do worse than average.) 

Is interferon a DMT?

In the early days of interferon therapy, there was debate about whether simply reducing the relapse rate by 30% relative to placebo treatment, without slowing down the worsening of the disease over 2 years, was disease-modification. However, subsequent trials and follow-up of people with MS treated with interferon-beta showed a slowing down of disease worsening, delays in developing secondary progressive MS and a favourable impact on survival.1 

Do symptomatic treatments modify the disease?

Symptomatic treatments improve the symptoms associated with MS without affecting the natural history. Treatments are classified as symptomatic in relation to their mode of action; but some classes of treatment may yet prove to be disease-modifying. For example, we often use sodium channel blocking agents, such as phenytoin, carbamazepine, oxcarbazepine and lamotrigine, for MS-related neuralgia and other pain syndromes. However, there is evidence that this class of therapy may be neuroprotective and hence disease-modifying. 

Who decides on eligibility for a licensed DMT?

Regulators decide in which group of people with MS the DMT can be used, and they grant a licence for its use. Regulators include the EMA, the FDA and the Medicines and Healthcare products Regulatory Agency (MHRA in the UK).

Payers hold the purse strings and decide which licensed drugs to make available. They makecost-effectiveness assessments to try and optimise the use of the drug in clinical practice. Payers include medical insurance companies and the NHS in the UK. 

Guidelines are formulated to help healthcare professionals use DMTs in the most appropriate way within a particular healthcare system. Guidelines often go much further than the regulators and payers, in that they try to address potential ambiguities in the prescribing of DMTs. National, regional or local guidelines that provide expert clinical guidance include the UK NICE (National Institute for Health and Care Excellence) MS management guidelines and the Association of British Neurologists guidelines. 

In the NHS in England, we must abide by NHS England’s algorithm that is predominantly based on NICE technology appraisals, NICE standards of care and the Association of British Neurologists guidelines. To navigate the specifics of the eligibility criteria is quite complex. However, a simpler way of looking at this is to start by defining how active your MS is. 

How does disease activity affect my treatment options?

To be eligible for DMTs, you must have active MS. A summary of the four categories of disease activity is given below. Further details can be found in the section entitled Do I have active MS?

  1. Inactive MS – you are not currently eligible for DMTs.
  2. Active MS – you should be eligible for a so-called platform therapy (interferon-beta, glatiramer acetate, teriflunomide, dimethyl fumarate or ponesimod) and ocrelizumab or ofatumumab.
  3. Highly active MS – you are eligible for all therapies except natalizumab. Please note in England fingolimod can only be used as a second-line therapy (after another DMT has failed).
  4. Rapidly evolving severe MS – you should be eligible for all DMTs.

Advanced or progressive MS

Ocrelizumab and siponimod are now approved in several countries for the treatment of active PPMS and active SPMS, respectively. A classification of active PPMS requires recent MRI evidence of disease activity, that is, the formation of new T2 lesions and/or the presence of gadolinium-enhancing lesions in the last 3 years. Active SPMS is confirmed by the occurrence of superimposed relapses and/or the presence of new T2 lesions and/or gadolinium-enhancing lesions in the last 2 years. Based on these very narrow definitions, most patients with PPMS and SPMS will not be eligible for ocrelizumab or siponimod, respectively. The differences between the MRI criteria for active PPMS and active SPMS reflect the reality that people with PPMS are less likely to be having regular monitoring MRI scans.

Stages of MS currently not eligible for treatment

In the UK, people with MS who are wheelchair users are not eligible for DMTs. The reason for this is that patients with more advanced MS have generally been excluded from phase 3 clinical trials; hence there are no data to show whether licensed DMTs are effective in this group.

There is a long-held view that inflammation is reduced or absent in advanced MS. However, clinical, imaging and pathological data show that inflammation still plays a large, and possibly a major, role in advanced MS. Therefore, not targeting more advanced MS with an anti-inflammatory is counterintuitive.

The importance of upper limb function

In 2016, the #ThinkHand campaign was launched to raise awareness of the importance of hand and arm function in people with MS and the need for clinical trials in this population. Studies currently ongoing that focus on limiting upper limb disability progression include ChariotMS (oral cladribine)2 in people with advanced MS (UK only) and the global, multicentre O’HAND trial  (ocrelizumab)3 in participants with PPMS. 

Once someone with MS becomes a wheelchair user, they still have neuronal systems that are potentially modifiable – for example, upper limb, bulbar (speech and swallowing), cognition and visual function. There is an extensive evidence base showing that several licensed DMTs can slow the worsening of upper limb function despite subjects having advanced MS. Now that ocrelizumab and siponimod have been licensed for active primary and secondary progressive MS, respectively, these DMTs may form the platform for future add-on trials. 

References

  1. Goodin DS, et al. Survival in MS: a randomized cohort study 21 years after the start of the pivotal IFNβ-1b trial. Neurology 2012;78:1315 ̶ 22.
  2. National Institute for Health and Care Research (NIHR). MS clinical trial to focus on people who can’t walk. November 2020. Available at https://www.nihr.ac.uk/news/ms-clinical-trial-to-focus-on-people-who-cant-walk/26227 (accessed June 2022).
  3. US National Library of Medicine. A Study to Evaluate the Efficacy and Safety of Ocrelizumab in Adults With Primary Progressive Multiple Sclerosis (O’HAND). First posted July 2019. Available at https://clinicaltrials.gov/ct2/show/NCT04035005 (accessed June 2022).