Multiple Sclerosis Discovery -- Episode 43 with Dr. May Han
Multiple Sclerosis Discovery: The Podcast of the MS Discovery Forum - Un podcast de Multiple Sclerosis Discovery Forum
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[intro music] Hello, and welcome to Episode Forty-Three of Multiple Sclerosis Discovery, the podcast of the MS Discovery Forum. I’m your host, Dan Keller. This week’s podcast features an interview with Dr. May Han, who discusses issues related to following patients with clinically isolated syndrome. But first, here are some new items on the MS Discovery Forum. We recently posted an article on a surprisingly strong association between a certain gene variant and non-response to interferon beta in people with RRMS. The study is a meta-analysis of three independent cohorts in Italy, France, and the U.S., and it comes from the labs of Philip De Jager and Filippo Boneschi. You’ll find this article by clicking first on News & Future Directions and then on New Findings. This past week we published the latest in our series of data visualizations. This month’s visualization is a series of word clouds illustrating how key terms in the MS clinical-trial literature have changed between 1993 and 2014. To find this visualization, first click on Research Resources, then on Data Visualizations, and then on Word Cloud. According to our curated list of the latest scientific articles related to MS, 30 such articles were published last week. To see last week’s list, go to msdiscovery.org and click on Papers. We selected one of those papers as an Editors’ Pick. It’s study of the association between depressive symptoms and walking ability in people with RRMS. Are you attending the annual meeting of the Consortium of Multiple Sclerosis Centers in Indianapolis this week? If so, please come visit us at the Accelerated Cure Project’s booth. We’ll be demonstrating some of our latest data visualizations along with other features of the MS Discovery Forum. You’ll find the booth in the hallway close to the main entrance to the exhibit hall, and we look forward to meeting you. [transition music] Now to the interview. Dr. May Han is an assistant professor in Neurology and Neurological Sciences at Stanford University. I spoke with her about following patients with clinically isolated syndrome, as well as her approach to patients with MS across the course of their disease. But first, she addressed some unmet needs in MS. Interviewer – Dan Keller Dr. Han, you told me that we’re good at the diagnosis of MS in general, but still there’s a vast area that we don’t know about. What are some of those unmet needs? Interviewee – May Han So it’s been over 150 years since Charcot first described multiple sclerosis, and I have to say that we have come a long way in understanding and treating this disease. But as you have mentioned, there are still areas where we have no idea, there are gaps in our understanding of this disease. One of these areas that is clinically very relevant and is very challenging is in the day and age where we have a dozen disease-modifying therapies for MS patients, and yet we don’t have a good way, a scientific way of selecting the most effective therapy for a particular patient is what I find quite challenging in the clinics. MSDF What gives you clues or how do you approach this essentially algorithm of deciding where to begin and how to move on to other medications if the first one’s not working well? Dr. Han Currently, of course, we follow the guidelines. So for any relapsing-remitting patients, our logic is to go for the safest medication that we think are going to be most effective, which means we go with the first-line therapies. So we have the convention ABC drugs such as beta-interferon family of therapies and glatiramer acetate, plus the newer oral medications such as Tecfidera and fingolimod or Gilenya that we use for the first-line therapy; not a whole lot of science in choosing these medications for a particular patient, but what we would do is initially we would educate the patient about these disease-modifying therapies and then select the medication together with the patient to see what would be most appropriate and the patient could be most compliant for a particular medication. To give you an example, certain patients have aversion to needles, in which case we go with the oral medications. We also have in mind what the preference of the patient, such as whether they could be able to follow it through for years on end with a particular medication. Ideally, we would like to have zero relapses or MRI activity when a patient is on a disease-modifying therapy, but as we all know none of these medications are 100% foolproof, and they can still have some degree of MRI activity or infrequent relapses on this medication. However, if a patient is clearly not responding to a therapy either in terms of not being compliant, being intolerant to the mode of administration, or if they’re having worsening disease activity, we would decide to go on to stronger medications or second-line of therapy. MSDF Do you initially discuss a plan of action, a stepwise pattern of medication prescribing, or do you wait until something needs to be changed to bring it up with patients? Dr. Han That is a very good question. I’m sure it varies among clinicians, but, however, I would like to paint the picture to the patient the best that I can. So, let’s say for example, if a patient who is a newly-diagnosed MS patient who has very few MRI lesions, I would discuss with them what the most appropriate medication could be. We would decide a medication and we would also give them an outline of what the followup plan would be and when we would be deciding to switch to a different therapy, and if so, which medications would be most likely appropriate for them, and also how we would monitor them. So by doing this, it gives the patient a better picture of their path and what to watch out for, and in my experience we have a better outcome with these patients. MSDF Do you find that once you achieve success in limiting relapses and lesions that the medication is fairly stable for a long time, or do you have to have an armamentarium that you keep moving through? Dr. Han So my model if a patient is responding to a medication, unless they have other side effects or reasons to switch, I would like to get the most mileage out of the medication as much as I can for a particular patient. However, if a patient, for example, has JC virus positivity, in which case even if they’re responding to Tysabri really well, there is a cutoff time point where we have to sit down and consider whether this patient should be switched onto a different medication to prevent the development of opportunistic brain inflammation such as PML, in which case what the next medication would be. And so we would sit down and talk the pros and cons; this conversation was started even before the patient was started on medication, but that would be the checkpoint. MSDF I suppose another aspect is do medications start to fail patients even after a long period of stability, or do they usually continue to be stable if the medication is working for some period of time? Dr. Han This is also a very pertinent question. MS patients, as we know, is very heterogeneous. Some of the patients, if they are stable on a medication, they would continue to do well on a medication for several years up to decades. However, some patients would have an initial improvement or stabilization of their disease, however in the later stages they would have worsening disease. And it is really unclear whether because their disease per se is getting worse or whether their body is rejecting the medication secondary to the immune response. And that is also one area that we should do research on to better understand this condition. MSDF When you say reject the medication, are you actually referring to an immune rejection such as with, say, interferon; I would think it would be less likely they would actually mount an immune response to a small molecule. Am I clear on that or not? Dr. Han I think we have quite a lot of information in terms of beta interferon therapies, because we clearly know that patients do tend to develop antibodies against beta interferon, especially the therapy. However, even that we don’t really know if all those antibodies are attacking the drug or whether they are just there. So just by finding the antibody alone is not enough to say that the patient is not responding to it; I think we need to use it hand-in-hand with the clinical response as well as the MRI activity. Getting to the second part of your question whether there’ll be less intolerance or rejection to the therapy if it were small molecules, but I don’t think we understand at the cellular or molecular level. For small molecules there could be receptor down-regulation, there could be availability or cellular sequestration, or even the prodrug being converted to an active drug, or how the breakdown process occurs. So when a patient does not respond anymore to a medication, we just know that the clinical response is worse, and we don’t really know whether it is because the disease activity has worsened or other aspects, pharmacodynamic or kinetic aspects of the system has changed in such a way that they no longer respond. So, again, we do need to do more research to have a better understanding. MSDF You have called it MS comes in many different flavors. Have you found that any medications are particularly good for different constellations of symptoms, or is everything about equal no matter how they present? Dr. Han Very good question as well. I think in the experimental models people know that MS, or central system autoimmunity, can have a bias towards one type of inflammation as opposed to the other. For example, some would say that certain medications are better to treat Th1 as opposed to the Th17 type of inflammation, however in human beings there’s no clear-cut Th1 MS or Th17 MS. I don’t think people have done enough studies to clearly decipher the immune profiles of patients. So the answer is we don’t know. MSDF Finally, let’s talk about the need for biomarkers especially very early in the disease when someone’s presenting with CIS which may or may not become MS. Where does that stand and how acute is the need? Dr. Han The need is there, especially if you look at it from a patient who just had an initial attack. If you tell them that we don’t really know whether this is a one-time thing or whether you’re going to develop MS, and we’ll have to wait and see for three-plus years. So for these three years, the patient’s life is very much consumed by the “is it going to be MS” kind of question. And it does affect their physical-mental wellbeing as well as their quality of life. I think we’ve come a long way with the advancement of the MRI studies in such a way that if a patient has MRI lesions together with the first-time attack, we could almost clearly say that this is going to blossom into MS. However, for patients who are radiographically clean and who just had one episode, it would be very, very helpful to have some kind of blood biomarkers to predict whether this could be a single event or whether it could be a central nervous system inflammatory disorder. MSDF You picked three years as a period of waiting, watching. Are they out of the woods after that, or how late can it blossom into full MS? Dr. Han It’s always a bell-shaped curve. There are patients who would declare themselves sooner than three years, there are also patients who would take several years before they have the second attack. I have one patient who had an initial attack of optic neuritis and nine years later she had the second attack. During that period, she had had MRI scans for three years which were clean. So, I guess, one is never completely out of the woods, but at the same time it is also not prudent to perform unnecessary tests on a patient. So I think we have to focus on what is the safety net and pick a period of time, but at the same time it is very important to educate a patient to symptoms to watch out for, how to get help, and to work very closely with the primary care physician or a neurologist so in case the symptoms show up they will not be ignored or delayed to receiving treatment. MSDF Is there anything we’ve missed or is important to add? I’m sure it’s a gigantic field, but is there anything glaring that should be added? Dr. Han I would like to encourage people in the field to also focus on the secondary-progressive stage of MS. We know that relapsing-remitting MS patients with or without therapy eventually would end up having secondary-progressive MS, so it’ll be really important to decipher whether during the secondary-progressive stage there is no inflammation but only the early neurodegeneration, or how the immune system and the central nervous system interact and how we can change it, or at least modulate it, to either delay or to prevent neurodegeneration. The third area that I think is very important is to try to understand the regenerative aspects of the central nervous system. As I have given you the example, if we have two patients who have had similar lesion burden or even lesions that are approximately the same in similar areas, a patient can be severely devastated, neurologically devastated, whereas the other may have minimal neurologic deficits. And we would always say that it depends on the brain reserve, or neural reserve, but we don’t quite know what it is. Is it the stem cells, is it the nervous system being more resistant to insult and how the immune system interacts with it? And I think this is also a big area that we should focus on, of course, to prevent further damage, but also once the damage is done to limit the damage and perhaps to regenerate it. And I think that people always have within themselves the ability to heal. MSDF Good, thank you. Dr. Han Thank you. [transition music] Thank you for listening to Episode Forty-Three of Multiple Sclerosis Discovery. This podcast was produced by the MS Discovery Forum, MSDF, the premier source of independent news and information on MS research. MSDF’s executive editor is Robert Finn. Msdiscovery.org is part of the non-profit Accelerated Cure Project for Multiple Sclerosis. Robert McBurney is our President and CEO, and Hollie Schmidt is vice president of scientific operations. Msdiscovery.org aims to focus attention on what is known and not yet known about the causes of MS and related conditions, their pathological mechanisms, and potential ways to intervene. By communicating this information in a way that builds bridges among different disciplines, we hope to open new routes toward significant clinical advances. We’re interested in your opinions. Please join the discussion on one of our online forums or send comments, criticisms, and suggestions to [email protected]. [outro music]