Just catching up with my reading. Whilst I was away on holiday the ASCLEPIOS I and II trials was published in the New England Journal of Medicine.
There is little doubt that ofatumumab is superior to teriflunomide when it comes to suppressing focal inflammation, i.e. relapses, MRI activity and peripheral blood neurofilament levels. However, ofatumumab’s effectiveness against teriflunomide on the real MS (delaying disability progression and reducing the relative loss of brain volume) is less impressive. Is this just another example of a dissociation between the anti-inflammatory effects of an anti-CD20 therapy and its impact on the end-organ as measured using brain volume loss or is it telling us something about teriflunomide and the cause of MS?
It is clear, at least to me, that MS the disease is not due to focal inflammation. Based on the Prentice criteria for disease surrogates, both relapse and focal MRI activity don’t predict disability outcomes in natural history studies and placebo arms of clinical trials. If focal inflammation was MS then relapses and focal MRI activity would predict outcome whether or not you are on a DMT. The point I making here may be a philosophical one, but it a critically important one. In comparison, sustained or confirmed disability progression has to be MS and is based on the pathological correlates that define MS (demyelination, neuroaxonal loss and gliosis).
So why does ofatumumab do so poorly on these metrics relative to teriflunomide, when you would expect it do better? I think teriflunomide is the outlier and this opinion is based on several observations.
Teriflunomide has effects on disability progression that are way and above what you expect from its impact on relapses and focal MRI activity; i.e. both teriflunomide phase 3 placebo-controlled trials were positive on disability progression, despite a moderate reduction in relapse rate (~33% vs. placebo).
Teriflunomide also has a significant and unexpected effect on brain volume loss compared to placebo, which again is out of proportion to its anti-inflammatory effects.
Teriflunomide is more effective when used 2nd and 3rd line. Teri is the only DMT to show the latter and this observation was seen in both phase 3 studies, which makes it likely to be a real, and a very important, finding.
Finally, teriflunomide is a broad-spectrum antiviral agent, which may be part of its mode of action in MS. Could teriflunomide be targeting the viral cause of MS independent of its effects on the immune system’s response to that virus? Could it be an anti-EBV agent? Although teriflunomide’s antiviral mode of action needs more study, I suspect this is the reason why teriflunomide is the outlier that disproves the dogma.
Despite these observations, I suspect the MS community is going to propel ofatumumab to blockbuster status within the first 12 months of its launch. However, I want to reiterate that I think anti-CD20 therapies are lulling us into a false sense of security, i.e. because anti-CD20 therapies are so good at suppressing relapses and focal MRI activity we think we have sorted out the treatment of MS. However, when you look carefully at the end-organ of pwMS on anti-CD20 it is clear that their brains are still being shredded by smouldering MS. It is clear to me that we need to go way and beyond ofatumumab and anti-CD20 therapies to target whatever is causing smouldering MS. This is why we need to think combination therapies and find an add-on therapy, possibly an antiviral, that normalises brain volume loss in people with MS who are rendered free of focal inflammatory activity.
BACKGROUND: Ofatumumab, a subcutaneous anti-CD20 monoclonal antibody, selectively depletes B cells. Teriflunomide, an oral inhibitor of pyrimidine synthesis, reduces T-cell and B-cell activation. The relative effects of these two drugs in patients with multiple sclerosis are not known.
METHODS: In two double-blind, double-dummy, phase 3 trials, we randomly assigned patients with relapsing multiple sclerosis to receive subcutaneous ofatumumab (20 mg every 4 weeks after 20-mg loading doses at days 1, 7, and 14) or oral teriflunomide (14 mg daily) for up to 30 months. The primary end point was the annualized relapse rate. Secondary end points included disability worsening confirmed at 3 months or 6 months, disability improvement confirmed at 6 months, the number of gadolinium-enhancing lesions per T1-weighted magnetic resonance imaging (MRI) scan, the annualized rate of new or enlarging lesions on T2-weighted MRI, serum neurofilament light chain levels at month 3, and change in brain volume.
RESULTS: Overall, 946 patients were assigned to receive ofatumumab and 936 to receive teriflunomide; the median follow-up was 1.6 years. The annualized relapse rates in the ofatumumab and teriflunomide groups were 0.11 and 0.22, respectively, in trial 1 (difference, −0.11; 95% confidence interval [CI], −0.16 to −0.06; P<0.001) and 0.10 and 0.25 in trial 2 (difference, −0.15; 95% CI, −0.20 to −0.09; P<0.001). In the pooled trials, the percentage of patients with disability worsening confirmed at 3 months was 10.9% with ofatumumab and 15.0% with teriflunomide (hazard ratio, 0.66; P=0.002); the percentage with disability worsening confirmed at 6 months was 8.1% and 12.0%, respectively (hazard ratio, 0.68; P=0.01); and the percentage with disability improvement confirmed at 6 months was 11.0% and 8.1% (hazard ratio, 1.35; P=0.09). The number of gadolinium-enhancing lesions per T1-weighted MRI scan, the annualized rate of lesions on T2-weighted MRI, and serum neurofilament light chain levels, but not the change in brain volume, were in the same direction as the primary end point. Injection-related reactions occurred in 20.2% in the ofatumumab group and in 15.0% in the teriflunomide group (placebo injections). Serious infections occurred in 2.5% and 1.8% of the patients in the respective groups.
CONCLUSIONS: Among patients with multiple sclerosis, ofatumumab was associated with lower annualized relapse rates than teriflunomide. (Funded by Novartis; ASCLEPIOS I and II ClinicalTrials.gov numbers, NCT02792218 and NCT02792231).
I am sure you have all read or heard a version of Goldilock’s and the three bears. Goldilocks finds one of the bears’ beds too hard, one too soft and the final bed is just right, which allows her to lie down and fall asleep.
At the moment the United States is having an existential crisis about the cost and value of its healthcare system. A series of articles in the New England Journal of Medicine (NEJM) is asking whether or not the massive amount of money that the US spends on healthcare is delivering good value for money. It is quite clear that the US is an outlier when you look at a simple integrator of population health outcome (see figure below).
At the same time that the NEJM is reflecting on the poor value that the US healthcare system delivers there are fundamental changes happening to healthcare delivery, which are being rapidly adopted because of the impact of the coronavirus pandemic.
As a person with a chronic disease is your MS being under-managed, over-managed or managed just right? Maybe you don’t know how to answer this question, because you don’t know what an ideal MS management pathway looks like.
A related issue is a fundamental battle been two ideologies that is currently playing out across the globe; the socialist European model of healthcare versus the neoliberal or capitalist US model of healthcare. Should the management of MS at a population level be value-based, i.e. based upon the utilisation of limited resources that deliver value by improving the length of life and/or increasing the quality-of-life experienced by a population of people with MS? This implies that the focus is on the population and not the individual.
I continue to be amazed when I hear senior MS neurologists make the claim they have never prescribed alemtuzumab or referred any of their patients for HSCT and don’t intend to do so either. These same neurologists seem to be happy with natalizumab and ocrelizumab as their #1 high-efficacy go to DMTs. When I challenge them with the exceptional longterm outcomes for pwMS treated early with alemtuzumab or HSCT I get a glazed look, which I now learnt is cognitive dissonance.
“Cognitive dissonance refers to a situation involving conflicting attitudes, beliefs or behaviours. This produces a feeling of mental discomfort leading to an alteration in one of the attitudes, beliefs or behaviours to reduce the discomfort and restore balance. For example, when people smoke (behaviour) and they know that smoking causes cancer (cognition), they are in a state of cognitive dissonance.” Source: Simply Psychology
It is quite clear that both ocrelizumab and natalizumab are very effective DMTs at switching-off focal inflammatory disease activity in MS; a large number of pwMS on these therapies are NEDA-2 (relapse-free and no new T2 lesions on MRI). This is interpreted by these neurologists and the wider MS community that MS is all sorted. Go away, get on with your life and be happy.
What these neurologists don’t tell their patients on ocrelizumab and natalizumab that despite no relapses or new MRI lesions the accelerated brain volume loss due to MS is continuing unabated. These neurologists and their patients are being lulled into a sense of false security because they believe MS is focal inflammatory disease, when in fact the real MS is the smouldering disease, which drives end-organ damage.
I have addressed these topics many times on this blog. If you are interested in reading some of my back catalogue of posts on this particular topic you can start with the posts below or you could watch a recent lecture I have given on the topic.
It is clear that not all DMTs are made equal when it comes to preventing end-organ damage. At the top of the league table are alemtuzumab and HSCT (~0.2-0.25% loss per annum). Both these treatments are NIRTs (non-selective immune reconstitution therapies).
Natalizumab is probably next with an annual brain volume loss in the region of 0.25-0.30% per annum. Ocrelizumab (anti-CD20) comes next with a rate of brain volume loss of ~0.374% per annum (see latest data below).
Why do natalizumab and ocrelizumab, despite being very effective anti-inflammatory DMTs have only a moderate impact on end-organ damage? This and other observations have convinced me that MS is not focal inflammation, which represents the immune system’s response to what is causing MS. I suspect there is something going in the CNS of pwMS that is the real MS; I refer to this hypothesis as the ‘Field Hypothesis’.
What these observations are telling us that peripheral B-cells are an important part of the immune response to the cause of MS, but B-cells are not necessarily involved in driving the true MS pathology, which is causing the progressive brain volume loss.
What does this mean for the well-informed person with MS? Firstly, you and your neurologist may not want to dismiss alemtuzumab and HSCT as a first-line, or at least early, treatment option. These non-selective highly effective IRTs differ from anti-CD20 therapies in that they target both B and T cells. I suspect we need to target both these cells types early in the course of the disease to really get on top of the real MS.
I am aware of the appeal of anti-CD20 therapies and natalizumab in that they are safer and easier to use because of less monitoring, however, this may come at a cost in the long-term. Please remember that once you have lost brain you can’t get it back. With alemtuzumab and HSCT, the risk is frontloaded, and balanced against the potential long-term gains in efficacy, which are unprecedented. Choosing a DMT on a rung or two lower down on the therapeutic ladder gives you better short-term safety and makes the life of your MS neurologist less stressful, because of less monitoring and fewer risks, but at a potential long-term cost to your brain and spinal cord.
This is why making an informed decision about which DMT you choose is a very complicated process and subject to subtle and often hidden effects of cognitive biases; cognitive dissonance is just one of these biases. The one bias I am very aware of is the ‘Gambler’s Dilemma’, be careful not to be lulled into a false sense of security by your beliefs; most gamblers eventually end-up losing.
In reality, we need to move treatment target in MS way beyond NEDA-2 to target end-organ damage, i.e. brain volume loss, T1 black holes, the slowly expanding lesions (SELs), neurofilament levels, cognition, sickness behaviour, OCBs, etc. Our treatment aim should be to ‘Maximise Brain Health’ across your life and not just the next few years.
As yet we don’t know what the impact of alemtuzumab and HSCT are on the pathology of smouldering MS, but these agents must be doing something to these pathologies based on clinical and MRI outcomes (see below). Despite this data gap, I think we have enough empirical evidence that alemtuzumab and HSCT are doing some fundamental to the pathology of MS.
Coming back to cognitive dissonance. It could be argued that if an MS neurologist or MS centre does not offer alemtuzumab or HSCT to at least some of their patients then they are not providing their patients with sufficient choice. In addition, they will almost certainly not accept the concept of smouldering MS being the real MS.
Objective: To assess over 3 years of follow-up, the effects of maintaining or switching to ocrelizumab (OCR) therapy on clinical and MRI outcomes and safety measures in the open-label extension (OLE) phase of the pooled OPERA studies in relapsing multiple sclerosis.
Methods: After 2 years of double-blind, controlled treatment, patients continued OCR (600 mg infusions every 24 weeks) or switched from interferon (IFN) β-1a (44 μg 3 times weekly) to OCR when entering the OLE phase (3 years). Adjusted annualized relapse rate, time to onset of 24-week confirmed disability progression/improvement (CDP/CDI), brain MRI activity (gadolinium-enhanced and new/enlarging T2 lesions), and percentage brain volume change were analyzed.
Results: Of patients entering the OLE phase, 88.6% completed Year 5. The cumulative proportion with 24-week CDP was lower in patients who initiated OCR earlier, vs patients initially receiving IFN β-1a (16.1% vs 21.3% at Year 5; p=0.014). Patients continuing OCR maintained, and those switching from IFN β-1a to OCR attained near complete and sustained suppression of new brain MRI lesion activity from Year 3 to 5. Over the OLE phase, patients continuing OCR exhibited less whole brain volume loss from double-blind study baseline vs those switching from IFN β-1a (–1.87% vs –2.15% at Year 5; p<0.01). Adverse events were consistent with past reports and no new safety signals emerged with prolonged treatment.
Conclusion: Compared with patients switching from IFN β-1a, earlier and continuous OCR treatment up to 5 years provided sustained benefit on clinical and MRI measures of disease progression.
Classification of evidence: This study provides Class III evidence that earlier and continuous treatment with ocrelizumab provided sustained benefit on clinical and MRI outcomes of disease activity and progression compared with patients switching from IFN β-1a. The study is rated Class III because of the initial treatment randomization disclosure that occurred after inclusion in OLE.
BACKGROUND: A cohort of patients with poor-prognosis multiple sclerosis (MS) underwent chemotherapy-based immune ablation followed by immune reconstitution with an autologous hematopoietic stem cell transplant (IA/aHSCT). This eliminated new focal inflammatory activity, but resulted in early acceleration of brain atrophy.
OBJECTIVE: We modeled the time course of whole-brain volume in 19 patients to identify the baseline predictors of atrophy and to estimate the average rate of atrophy after IA/aHSCT.
METHODS: Percentage whole-brain volume changes were calculated between the baseline and follow-up magnetic resonance imaging (MRI; mean duration: 5 years). A mixed-effects model was applied using two predictors: total busulfan dose and baseline volume of T1-weighted white-matter lesions.
RESULTS: Treatment was followed by accelerated whole-brain volume loss averaging 3.3%. Both the busulfan dose and the baseline lesion volume were significant predictors. The atrophy slowed progressively over approximately 2.5 years. There was no evidence that resolution of edema contributed to volume loss. The mean rate of long-term atrophy was -0.23% per year, consistent with the rate expected from normal aging.
CONCLUSION: Following IA/aHSCT, MS patients showed accelerated whole-brain atrophy that was likely associated with treatment-related toxicity and degeneration of “committed” tissues. Atrophy eventually slowed to that expected from normal aging, suggesting that stopping inflammatory activity in MS can reduce secondary degeneration and atrophy.
OBJECTIVE: To describe detailed MRI results from 2 head-to-head phase III trials, Comparison of Alemtuzumab and Rebif Efficacy in Multiple Sclerosis Study I (CARE-MS I; NCT00530348) and Study II (CARE-MS II; NCT00548405), of alemtuzumab vs subcutaneous interferon β-1a (SC IFN-β-1a) in patients with active relapsing-remitting multiple sclerosis (RRMS).
METHODS: The impact of alemtuzumab 12 mg vs SC IFN-β-1a 44 μg on MRI measures was evaluated in patients with RRMS who were treatment-naive (CARE-MS I) or who had an inadequate response, defined as at least one relapse, to prior therapy (CARE-MS II).
RESULTS: Both treatments prevented T2-hyperintense lesion volume increases from baseline. Alemtuzumab was more effective than SC IFN-β-1a on most lesion-based endpoints in both studies (p < 0.05), including decreased risk of new/enlarging T2 lesions over 2 years and gadolinium-enhancing lesions at year 2. Reduced risk of new T1 lesions (p < 0.0001) and gadolinium-enhancing lesion conversion to T1-hypointense black holes (p = 0.0078) were observed with alemtuzumab vs SC IFN-β-1a in CARE-MS II. Alemtuzumab slowed brain volume loss over 2 years in CARE-MS I (p < 0.0001) and II (p = 0.012) vs SC IFN-β-1a.
CONCLUSIONS: Alemtuzumab demonstrated greater efficacy than SC IFN-β-1a on MRI endpoints in active RRMS. The superiority of alemtuzumab was more prominent during the second year of both studies. These findings complement the superior clinical efficacy of alemtuzumab over SC IFN-β-1a in RRMS.
CLASSIFICATION OF EVIDENCE: The results reported here provide Class I evidence that, for patients with active RRMS, alemtuzumab is superior to SC IFN-β-1a on multiple MRI endpoints.
BACKGROUND: Tissue damage in both multiple sclerosis (MS) lesions and normal-appearing white matter (NAWM) are important contributors to disability and progression. Specific aspects of MS pathology can be measured using advanced imaging. Alemtuzumab is a humanised monoclonal antibody targeting CD52 developed for MS treatment.
OBJECTIVE: To investigate changes over 2 years of advanced magnetic resonance (MR) metrics in lesions and NAWM of MS patients treated with alemtuzumab.
METHODS: A total of 42 relapsing-remitting alemtuzumab-treated MS subjects were scanned for 2 years at 3 T. T1 relaxation, T2relaxation, diffusion tensor, MR spectroscopy and volumetric sequences were performed. Mean T1 and myelin water fraction (MWF) were determined for stable lesions, new lesions and NAWM. Fractional anisotropy was calculated for the corpus callosum (CC) and N-acetylaspartate (NAA) concentration was determined from a large NAWM voxel. Brain parenchymal fraction (BPF), cortical thickness and CC area were also calculated.
RESULTS: No change in any MR measurement was found in lesions or NAWM over 24 months. BPF, cortical thickness and CC area all showed decreases in the first year followed by stability in the second year.
CONCLUSION: Advanced MR biomarkers of myelin (MWF) and neuron/axons (NAA) show no change in NAWM over 24 months in alemtuzumab-treated MS participants.
When your neurologist looks in your eyes with an ophthalmoscope he/she is looking for the telltale signs of previous damage to the optic nerve. The sign we look for is optic disc pallor. The optic disc is made up of nerve fibres from the retina, which then pass out of the back of the eye to form the optic nerve. If you have had optic neuritis in the past and have lost nerve fibres this can be detected with an ophthalmoscope, OCT (optical coherence tomography) or with retinal photography. Nerve fibre loss from optic neuritis makes the optic disc look pale (see figure below).
The optic disc receives its blood supply from small arteries from the back of the eye; the amount of blood is proportional to the number of nerve fibres in the optic disc. The lower the number of nerve fibres the fewer blood vessels there are the paler the disc looks. Please remember red blood cells are red and give a health optic disc a pinkish colour (see top images above).
Did you know that with a typical attack of optic neuritis you lose about 20% of the nerve fibres in the eye? If you lose so many nerve fibres why isn’t your vision so badly affected in that eye? That is simply because your visual system is able to compensate for the damage; it has spare capacity. Despite this most pwMS who have optic neuritis will know that although their visual acuity, or gross vision, may have recovered they have subtle deficits that we don’t routinely test for. For example, colour vision is often abnormal; colours appear washed out. Contrast sensitivity is abnormal; you may have difficulty distinguishing between shades of grey. Depth perception is all over the place; you need binocular (both eyes) vision for accurate depth perception. If you have poor depth perception you may see things in 3D when they should be in 2D and you may have difficulty judging distances. You may also find that you are hypersensitive to bright lights or lights with certain wavelengths; I find a lot of pwMS become intolerant of fluorescent lights after an attack of optic neuritis.
The problem with the COVID-19 induced changes in our MS service is that with remote consultations I can do this aspect of the neurological examination. Is it important? Yes, firstly it allows one to determine what neuronal systems have been affected by MS, which is required for diagnosis, i.e. dissemination of disease in space, and secondly for assessing your EDSS or Expanded Disability Status Scale.
I am telling you all this as we developed a web-EDSS that requires you to know if your neurological examination is normal or abnormal. Having optic disc pallor is one clinical sign that may affect the EDSS. If you can’t get this information from your neurologist you can get a reasonable idea if your optic nerve has been affected by MS by downloading and using one of the many colour vision applications on your smartphone; we recommend using ‘eye handbook’ as it is free. So before completing your webEDSS you will need to know if you have abnormal colour vision in your left or right eye; this could be used as a proxy for optic nerve involvement. Please note if you have congenital colour blindness, which is more common in males, you can’t use this sign as a proxy for optic nerve involvement.
An interview with Rachel Horne who wrote the extraordinary blog post “The Kingdom of the Sick” (14th July 2020), which in my opinion is almost certainly the most well written and insightful piece on this blog.
CoI: nothing relevant in relation to this blog post
I have been asked many times about how COVID-19 is affecting our MS research programme. The short answer is massively and its true impact is yet to be realised because we are a far way off from anything that feels and looks like normal. We are still paralysed by the threat of a second wave of COVID-19; the social distancing requirements within the NHS means everything is going to be at half-mast and then the knock-on effects on research funding have yet to be felt.
I am having sleepless nights about the covert threats of upcoming redundancies, whether or not our soft money will dry up, which we rely on to support administrative staff and prime research, how would one goes about declaring that you are academically bankrupt and then the massive increase in the teaching workload as we reconfigure all our teaching courses to go online. I have never worked harder and felt more unsettled than I do now.
A good example of COVID-19’s knock-on effects is our #ThinkHand campaign. For those of you who have been following this blog for years should remember it well. The central theme of the campaign ‘is not to write-off people with MS who have lost their lower limb function and are now having to use a wheelchair’. We have hypothesised and put forward a theory that MS is modifiable throughout its course and want to do clinical trials in people with advanced MS who are wheelchair users. The article by Timmermans and colleagues below shows that leg function declines earlier and quicker than arm function in MS, which supports our so-called ‘length-dependent axonopathy model of MS’.
Our #ThinkHand campaign started about 6 years ago and has resulted in the design and funding of two clinical trials targeting advanced MS. ORATORIO-HAND will be testing ocrelizumab in advanced PPMS (i.e. up to an EDSS of 8.0) and CHARIOT-MS that will be testing oral cladribine in advanced MS, including subjects with either SPMS and PPMS with an upper EDSS cut-off of 8.5. In both these trials, we will be using the 9-hole peg test as the primary outcome. The initiation and/or recruitment of subjects for both these trials have been suspended for the last 4 months and is unlikely to restart for another 2-3 months and maybe longer. We are talking about 6 months or more in COVID-19-related delays. If ‘Time is Brain’ or in the case of these trials ‘Time is Loss of Hand Function’ then these delays may mean that many pwMS will have progressed beyond the eligibility cutoffs for these trials.
We are not the only ones that have been affected and maybe it doesn’t help complaining. A very good friend of ours has cancer that is potentially terminal; as a result of COVID-19, her potentially life-saving surgery has been delayed by over 3 months. This week’s BMJ highlights the plight of cancer patients in the NHS and suggests that COVID-19 may result in 45,000 excess cancer deaths. What is the equivalent figure for people with MS? Will it be 10,000 people with MS lose their independence because of the progression of their MS and loss of upper limb function? Or 8,000 people with MS become unemployed because of worsening disability are a result of subclinical worsening cognition?
My philosophy is to simply get up each morning and try and get on with the task at hand. My motivation comes from an unusual source; a book “The Boy, the Mole, the Fox and the Horse” that my wife gave me at the beginning of lockdown. The quote that sums up the right attitude is the one about storms.
“What is the best thing you’ve learnt about storms?”
Background and aims: From a clinical perspective there is a difference in the decline of arm and hand function and leg function in patients with multiple sclerosis (PwMS). Therefore, this study investigated the course of walking and arm and hand functions in PwMS over the first 10 years after diagnosis, including whether any function declined earlier or faster.
Methods: A long-term prospective follow-up study of an incidence cohort of 156 patients with a definite diagnosis of MS, either non-relapse onset (n=28) or relapse onset (n=128) type. Participants were systematically examined immediately after definite diagnosis, at 6 months, and at 1, 2, 3, 6 and 10 years. Walking was determined with the fast 10-meter timed walk test (10mTWT), arm and hand function with the Action Research Arm test (ARAT) and the nine-hole peg test (9HPT). The 10-year trajectories of walking and arm and hand functions were compared using standardized z-scores.
Results: From 3 years onwards the z-scores of the arm and leg function were visually diverging, with a trend towards significance at 6 years, and at 10 years the 10mTWT z-score is significantly higher than the 9HPT. This difference is more pronounced in non-relapse onset patients than in patients with relapse onset type MS, but present in both groups over the first 10 years. In the non-relapse onset group a difference in z-scores at 10 years post-diagnosis between the 10m TWT and 9HPT was found of -12.94 (95% confidence interval (CI) -20.2 to -5.73) for the right and -10.14 (95% CI -17.3 to -2.93) for the left hand. In the relapse onset group there was a difference at 10 years post-diagnosis of -2.17 (95% CI -3.75 to -0.59) for the right and a difference of -2.29 (95% CI -3.87 to -0.71) for the left hand.
Conclusion: This is the first longitudinal study that shows that walking declines earlier and more rapidly than arm and hand function in patients with MS. These results give important insights that can be linked to the pathophysiological disease process regarding the ascending order of deterioration in patients with MS.
Trials of anti-inflammatory therapies in non-relapsing progressive multiple sclerosis (MS) have been stubbornly negative except recently for an anti-CD20 therapy in primary progressive MS and a S1P modulator siponimod in secondary progressive MS. We argue that this might be because trials have been too short and have focused on assessing neuronal pathways, with insufficient reserve capacity, as the core component of the primary outcome. Delayed neuroaxonal degeneration primed by prior inflammation is not expected to respond to disease-modifying therapies targeting MS-specific mechanisms. However, anti-inflammatory therapies may modify these damaged pathways, but with a therapeutic lag that may take years to manifest. Based on these observations we propose that clinically apparent neurodegenerative components of progressive MS may occur in a length-dependent manner and asynchronously. If this hypothesis is confirmed it may have major implications for the future design of progressive MS trials.
It is clear that centrally acting anticholinergic drugs, which block so-called muscarinic receptors, are being used by many people with multiple sclerosis as DIY agents to promote remyelination. The scientific rationale for this practice is based on preclinical work in cell culture systems and animal models and one proof-of-concept study of clemastine in pwMS with previous optic neuropathy.
Is this practice wise? I say no. We need properly controlled large studies to confirm the results and show that clemastine and other drugs in this class are remyelinating, have a clinical effect that is meaningful and improve quality of life.
Why am I being so pessimistic? The problem is centrally-acting anticholinergic affect cognition. Oxybutynin, a first-generation CNS-penetrant anticholinergic, which is commonly prescribed for urinary frequency, reduces the average IQ of someone with MS by 7 points or half a standard deviation. This is a massive drop in cognitive function particularly if you already have cognitive impairment, which may be overt or hidden and is very common in pwMS.
I have been waging a war with many continence services who look after my patients who still use oxybutynin because it is cheap. There are many alternative newer anticholinergic agents that don’t penetrate the CNS or work on a different mechanism. So if you are on oxybutynin you need to switch drugs.
Lessons from the opicinumab phase 2 remyelination trial suggests that only a subset of pwMS are likely to benefit from a remyelinating agent. This is because not everyone with MS has demyelinated axons or nerve fibres that need remyelination. The estimate is that in pwMS with moderate disability (EDSS 2.0-5.5) only a third will benefit from a remyelinating agent. So if you are taking clemastine you may be taking a hit on your cognition when you don’t even know if you are one of those people who has a population of nerve fibres that are ready to be remyelinated.
For how long do you have to take a remyelination drug to achieve maximum benefit? Provided your MS is under control with an anti-inflammatory DMT and you are not demyelinating new axons you may only need a remyelination agent for a few weeks or months. Once you have stimulated remyelination and all the naked axons are remyelinated there is no need to continue taking the remyelination agent.
Please note these concepts about remyelination are based on animal models and early trials and are mostly hypothetical when it comes to pwMS.
Another worrying observation about anticholinergic drugs is that the impact on cognition may be irreversible and reduce your brain reserve. Several epidemiological studies have shown that in the general population 2-3 years of continuous anticholinergic exposure increases your risk of getting dementia by ~30%. Whether this is applicable to pwMS is at present unknown, but I can’t think of any reason why the MS brain would be less susceptible to anticholinergics; in fact, I suspect the MS brain may be more susceptible as pwMS have reduced brain and cognitive reserve.
So if you are taking off-label clemastine for its unconfirmed benefits in MS or another anticholinergic that is CNS penetrant my advice would be to stop taking them and to seek alternative cognition-friendly medication.
Please be aware that there are many drugs that have anticholinergic effects; the following website lists them. In addition, apart from blunting cognition the list of side effects attributable to anticholinergics includes the following:
Dry mouth
Difficulty in swallowing
Constipation
Paralytic ileus (paralysis of the bowl)
Nausea or vomiting
Increased heart rate
Urinary retention
Difficulty in urinating
Blurred vision
Dry eyes
Exacerbation or precipitation of acute angle-closure glaucoma
Decreased sweating
Drowsiness or sedation
Dizziness
Hallucinations
Deliriums
Restlessness
Irritability
Nervousness
Slurred speech
Impaired concentration
Confusion
Memory impairment
Postscript 1: I have been asked which of the anticholinergics used for MS-related bladder dysfunction are the safest. The table below indicates that Trospium is by far the least CNS penetrant; is the least lipid-soluble and the most positively charged. It is clear that oxybutynin is the worst. Tolterodine, darifenacin and solifenacin are in between.
Postscript 2: I have also been asked about what dose of drug X or drug Y is sufficient to cause anticholinergic cognitive effects. A good example on this list is Amitriptyline; just 10mg of Amitriptyline per day is sufficient.
I attended an online meeting yesterday and gave my usual talk on why the MS community needs to change its worldview from MS being a “clinico-radiological” entity to being a “biological disease”. There are many reasons for doing this but an alternative MS worldview will allow us to (1) diagnose MS earlier, (2) start treatment earlier, (3) define prevention strategies targeting very early MS or the at-risk, (4) stop MS being considered two or three diseases, (5) develop combination therapies for smouldering or the real MS and (6) to manage MS more holistically.
If we think about MS from a biological perspective rather than a clinical (relapses) or MRI (new lesion) perspective then we will not be lulled into a sense of false security that we are on top of this disease or be surprised when patients who are apparently disease-activity free become secondary progressive.
One of the participants and respected colleague asked me what will it take to get the MS community to accept the biological definition of MS and to move away from the clinico-radiological view of the disease. I tried to answer the question but failed horribly.
On reflecting on my inability to answer this question I realised that I have probably been trying to do this, i.e. redefine MS, for decades and have failed. My research, traditional communication channels (journals, congresses, etc.) and new media platforms (blogging, social media, etc) are clearly not working.
Maybe the solution is to create a parallel MS universe, i.e. set-up an alternative committee to redefine the disease. This ‘New MS Definition Committee’ would use sound philosophical principles to define MS, avoid the diagnostic tautology that underpins the McDonald criteria, and include definitions that are underpinned by biology. We can then retrospectively validate these criteria on existing data sets, refine the criteria (feedback loop) and then set-up prospective studies to validate the criteria. Yes, validate them, i.e. establish the sensitivity and specificity of the criteria and to then establish how they perform in high, intermediate and low prevalence regions of the world. What clinicians and researchers need to know is the positive and negative predictive value of the criteria in their clinics. You will be surprised by how much incorrect diagnoses or misclassifications affect research outcomes (more on this later).
This parallel MS Universe will have to include a different research and education agenda to challenge the current dogma. And will have to generate a few creative memes (infectious ideas) and policy to speed up adoption.
I wonder how many of my colleagues would want to join this parallel Universe? Is the status quo tenable? The motivation for doing this is to improve outcomes for people living with MS and to prevent the next generation of people getting MS.
In patients who I think are vulnerable, I always try to take the time to look at their feet. Unfortunately, because of COVID-19-induced NHS service changes, this is very difficult using telemedicine.
Poor foot hygiene and uncut toenails are in my experience an integrator of neglect. As the feet are generally hidden from view people with MS often neglect their foot hygiene more than other aspects of their grooming. Poor foot hygiene is not intentional, but simply represents the reality of living with a disability. Poor eyesight, double vision, oscillopsia, weakness, tremor, loss of feeling in the hands, slow movement, incoordination, obesity, etc. are all more common in pwMS and make cutting your own toenails difficult.
During COVID-19 lockdown nail bars have been closed and podiatrists have not been seeing patients; therefore, I suspect general foot hygiene may have deteriorated in many people with more advanced MS.
There is little doubt that MS or physical disability is a risk factor for onychogryphosis; in plain English overgrown and neglected toenails. Onychogryphosis makes it difficult to wear shoes, causes pain and may even put mobile patients at risk of falls. So if you can’t manage to look after your own feet I suggest post-lockdown setting-up regular appointments to have your toenails cut and your feet examined by a podiatrist. Please note in the UK podiatry is an NHS service.
Marginal gains, i.e. focusing on small differences which add up can make big differences to the quality of life and health outcome for people with MS, and this should include foot hygiene and taking care of your toenails. This is just another factor that HCPs need to consider if they want to manage MS holistically.
I have been telling people that an effective SARS-CoV-2 vaccine is a long way away and that we shouldn’t expect a commercially available vaccine for another 12-18 months. Maybe I am wrong. The Moderna phase 1 results were published by the NEJM yesterday and are more impressive than I expected. These results are so important because the vaccine is based on RNA technology, which is relatively easy to scale-up in terms of production, unlike recombinant protein vaccines or inactivated viral vaccines. Therefore this vaccine may be with us before the end of the year.
The Moderna RNA vaccine carries the code for S-2P antigen, consisting of the SARS-CoV-2 glycoprotein. The vaccine is given as two doses (Day 1 and Day 29) into the deltoid or shoulder muscle. The RNA then uses the molecular machinery of the deltoid muscle to make the immunogen that then stimulates the immune response to the antigen, which will hopefully prevent wild-type SARS-CoV-2 infection and prevent COVID-19.
This has potential implications for how we treat MS. It increases the likelihood of a successful vaccine to prevent COVID-19 and increases the chances of pwMS having to be vaccine-ready in a 6-9 month time scale rather than a 12-18 months period. Clearly this has implications for how we manage patients on DMTs that have been shown to blunt or prevent protective vaccine responses, in particular, pwMS on anti-CD20 therapy (rituximab, ocrelizumab, ofatumumab) or S1P-modulators (fingolimod, siponimod, ozanimod, ponesimod).
Will Prof G have to eat humble pie or his hat? The market response to the data below suggests he will. What will be the implications for the MS DMT market? I suspect an effective coronavirus vaccine will hit the anti-CD20 market the most, which means ofatumumab’s MS launch will be a damp squib.
BACKGROUND: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in late 2019 and spread globally, prompting an international effort to accelerate development of a vaccine. The candidate vaccine mRNA-1273 encodes the stabilized prefusion SARS-CoV-2 spike protein.
METHODS: We conducted a phase 1, dose-escalation, open-label trial including 45 healthy adults, 18 to 55 years of age, who received two vaccinations, 28 days apart, with mRNA-1273 in a dose of 25 μg, 100 μg, or 250 μg. There were 15 participants in each dose group.
RESULTS: After the first vaccination, antibody responses were higher with higher dose (day 29 enzyme-linked immunosorbent assay anti–S-2P antibody geometric mean titer [GMT], 40,227 in the 25-μg group, 109,209 in the 100-μg group, and 213,526 in the 250-μg group). After the second vaccination, the titers increased (day 57 GMT, 299,751, 782,719, and 1,192,154, respectively). After the second vaccination, serum-neutralizing activity was detected by two methods in all participants evaluated, with values generally similar to those in the upper half of the distribution of a panel of control convalescent serum specimens. Solicited adverse events that occurred in more than half the participants included fatigue, chills, headache, myalgia, and pain at the injection site. Systemic adverse events were more common after the second vaccination, particularly with the highest dose, and three participants (21%) in the 250-μg dose group reported one or more severe adverse events.
CONCLUSIONS: The mRNA-1273 vaccine induced anti–SARS-CoV-2 immune responses in all participants, and no trial-limiting safety concerns were identified. These findings support further development of this vaccine. (Funded by the National Institute of Allergy and Infectious Diseases and others; mRNA-1273 ClinicalTrials.gov number, NCT04283461
