Multiple Sclerosis Discovery: The Podcast of the MS Discovery Forum Multiple Sclerosis Discovery Forum

Accelerated Cure Project Newsletter - April 2018

Accelerated Cure Project Newsletter - January 2018

[intro music]
 
Host – Dan Keller
Hello, and welcome to Episode Ninety-eight of Multiple Sclerosis Discovery, the podcast of the MS Discovery Forum. I’m Dan Keller.
 
Today's interview again features Dr. David Baker, Professor of Neuroimmunology at Queen Mary University of London in the U.K. We spoke at the ECTRIMS conference last fall. In part one of our interview he raised the issue of why there has been very poor translation from animal models to clinical trials. Today, Dr. Baker, also known as the ”Mouse Doctor” for his work with animal models, lays out why this situation exists and what to do about it.
 
Interviewee – David Baker
I think there’s many reasons why, and I think we all have our failings. And one can point the finger at the animal models, which a lot of the clinicians do, saying it’s the animal model’s fault, which is possible. But I think also we have to look at humans and how humans use their animal models. And then how humans translate the data from the animal models into the clinic, because I think there’s many failings along the line, and I think that’s one of the reasons for the failing between the two.
 
I think one of the failings is, in terms of the animal models, that when we do our animal models for these, we’re looking for mechanisms not treatments. And so about 70% of studies give drug before disease is ever induced, which never happens in a human. You know, you go after you’ve had one or two or more attacks before you’re given drugs. We also use the drugs in a way that are never used in a human, so people will do what they call a prophylactic drug where they’ll give it before the disease manifests itself. Or a therapeutic dose, which is probably when the animals are showing their symptoms. But in reality, a human would be getting steroids at that time point. They would never get a DMT. So you’re not comparing, you know, apples with apples. You’re comparing apples with pears, and I think that’s one of the problems.
 
And I think, you know, if you try and block an immune response from being generated, that’s quite easy compared to stopping an immune response once it’s been generated, because immunity’s about giving life-long protection against infections. And so I think it’s a different type of beast to target. So I think this is where the animal models could do it, because EAE is one of the few where you have this relapsing-remitting disease course. But it’s very, very rare that people actually start to treat in between attacks to block further relapses. I think that’s one of the problems.
 
The other big problem is the dose; the dose relationship between animals and humans. There’s a tendency we just keep giving more and more and more and more, and eventually the drugs will work. But you’ve got this problem that animals are very liable to be stressed, and we call it the building site effect, so construction site effect. And if you have lots of loud noises, it scares animals. They get very stressed, and your EAE just disappears. And likewise, if you just give lots and lots of drug, that probably tastes nasty. They get stressed out as well. And I think many of the so-called wonder cures – cures of the week – are because we’re just giving too much, which doesn’t have a relationship to what the human dose is going to be.
 
And then, likewise, I think we’ve got too much of a publication bias for the need to generate positive data. And I think what we then have to do is we have to look at the quality of the data. And I think there has been a lot of failure to replicate data. I think some of that is because some studies lack quality control, and the way I look at that – and I could be wrong; obviously it’s an opinion – but if you look at the way that EAE is scored (it’s normally a scoring system 1 to 3 or 1 to 4) and then you have your drug, which may be, you know, takes your control down from 3 down to a 1. Bu

[intro music]
 
Host – Dan Keller
Hello, and welcome to Episode Ninety-seven of Multiple Sclerosis Discovery, the podcast of the MS Discovery Forum. I’m Dan Keller.
 
Today's interview features Dr. David Baker, Professor of Neuroimmunology at Queen Mary University of London in the UK. We spoke at the ECTRIMS conference last fall, where I asked him about his work with cannabinoid compounds – work that has led to a better understanding of the cannabinoid system as well as to candidate drug compounds to treat spasticity.
 
Interviewer – Dan Keller
In terms of what you're doing now with cannabinoids, can you tell me what you are looking for, and what you've found?
 
Interviewee – David Baker
Many, many years ago, we actually were probably the first people to show that cannabis can actually alleviate muscle stiffness in animal models of multiple sclerosis, which then kind of underpinned the push to look for cannabis in MS. So people with MS were smoking cannabis and perceiving benefit. The question was, why? And what they didn't really understand that there was going to be an unfolding biology. And a few years later after our first discovery that actually cannabinoids can cause relaxation of the muscles, we understood that the function of the cannabinoid system is to regulate nerve signaling. And so because the cannabinoid system does regulate the strength of synaptic signaling, then it's obvious that it can inhibit signs and symptoms because of this excessive neurostimulation. So at the time of that, then we realized that the receptor is a CB1 receptor, and the compound within cannabis is THC, and they're the same molecules that cause all the side effects. So you could never really disassociate away the high from the medical benefit. So we started to think, well, how can we try and get the medical benefit from the cannabinoid system and at the same time try and limit the side effect potential.
 
So what we thought is, well, if we can stop the cannabinoid molecules getting in the brain, then they won't cause the side effects. But maybe we can target the aberrant signaling in the spinal cord and the peripheral system to try and get the benefits. And so that was our intention. So we tried to make a CNS-excluded drug. And that's, in fact, what we did. We made a drug that was very, very water soluble, so you know, you use the mechanism of the blood-brain barrier to actually exclude it from the brain. So we made the compound, and a few weeks later, we kind of started putting it into animal models, not really doing it the pharmaceutical way, which would be a methodical testing. So we showed that it didn't cause any of the unwanted side effects that are associated with cannabis in the animals. And then we put it in a system where we had a spasticity in a multiple sclerosis relevant system, and the drug worked.
 
Now what we did know is that the drug was blocked by the activity of the CB1 receptor antagonist, so it looked like we'd made what we set out to make. So we were really excited. And from that point, we started to try and see if we could develop it as a drug. Unfortunately what we realized very quickly actually is that it doesn't work by the known cannabinoid receptor system, and I think what we stumbled across is a whole new biology of the cannabinoid system.
 
And so we've been developing this drug bit by bit. We set up a university spinout company to try and develop it as a pharmaceutical drug. And over the years, bit by bit, we've been pushing it forward. So it's very safe in animals. It has a massive therapeutic window. And with grant funding agencies etc. we've managed to be able to take it into phase I study where it passed with flying colors. We tested it in 60 healthy humans. And a few weeks ago, we started our first testing in people with multiple sclerosis. So we'll have to see how it works. But we hope by early in 2016 we'll have the answer. So it could be a symptom modifying drug, b

[intro music]
 
Host – Dan Keller
Hello, and welcome to Episode Ninety-six of Multiple Sclerosis Discovery, the podcast of the MS Discovery Forum. I’m Dan Keller.
 
Today's interview features Drs. Bibiana Bielekova, who is an investigator at the National Institutes of Health, and Mika Komori, a postdoctoral fellow in her lab. We caught up with the two physician-researchers at the ACTRIMS meeting in New Orleans earlier this year. At the meeting, Dr. Komori talked about a new and more sensitive way to evaluate what may be happening in the brains and spinal cords of people with progressive MS.
 
In a recent study, she examined samples of cerebral spinal fluid, or CSF, collected through a thin needle near the base of the spine. She was scouting for immunological biomarkers of progressive MS. In the analysis, a molecule called CD27, mostly from T cells, stood out, as did another marker specific to B cells. Even more revealing was the ratio of the CD27 molecule to the T cells. T cells are a big player in relapsing MS and not usually associated with the progressive, more neurodegenerative forms of MS. The unexpected results raise new questions about why immune-modulating drugs do not seem to be effective against progressive MS.
 
If validated, the new test may lead to better diagnosis and treatment of people with MS and other neurological disorders. And it may speed up clinical trials in progressive MS and reduce their cost. In fact, the same research team used their new biomarker test in a small phase 2 study of the anti-B cell drug, rituximab, delivered both intravenously in the blood and intrathecally in the spinal column. Unfortunately, the new biomarker test showed that the double delivery system did not work as expected to eliminate inflammatory B cells trapped in the brains of people with progressive MS. They stopped the study early for lack of efficacy.
 
In a change to our usual podcast format, Dr. Bielekova interviewed Dr. Komori about the specifics of the study and put the results in a larger context. Midway through the interview, Carol Morton, a past editor of MS Discovery Forum, asked both doctor-scientists about what the new test means for treating patients.
 
Interviewer – Dr. Bibiana Bielekova
As a physician, when we see patients, we don’t really know what’s happening in their brains, right? We are using some tools that are supposed to help us to identify like, for example, MRI, but they are not perfect. So, how did you choose to address that problem?
 
Interviewee – Dr. Mika Komori
So, when I saw patients, I can’t tell them that the drug, which are now available, is effective or not, especially for progressive MS patients, because currently so far all big clinical trials, they didn’t show any effects on them. Because of that result, we think progressive MS patients don’t have any intrathecal inflammation. So far we believe MS – multiple sclerosis – is inflammatory disease, but we don’t know if it’s true for progressive MS or not.
 
Dr. Bielekova
Yes, and, in fact, it is because these tools are not that ideal, right? So, in fact, by using the tools that are available, such as MRI or these cerebrospinal fluid markers that have been developed more than 40 years ago, the conclusion is that there isn’t inflammation in progressive MS, right, because all of them are basically decreased, with exception of IgG index which, as you said, remains stable for many, many years. So somebody who had, for example, infection during childhood can have elevated IgG index for the rest of their life.
 
So that was really the reason why we wanted to develop something that is more sensitive. And also, I think, the question really was, does cerebrospinal fluid reflect what’s happening in the brain tissue? And can we somehow develop technology that can tell us what is happening in the brain tissue without taking, of course, the biopsy, which is extremely invasive, and we cannot re

[intro music]
 
Host – Dan Keller
Hello, and welcome to Episode Ninety-five of Multiple Sclerosis Discovery, the podcast of the MS Discovery Forum. I’m Dan Keller.
 
Today's interview features Dr. Michael Levy, associate professor of neurology at Johns Hopkins University. When we met in his office, he told me about his work on the role of T cells in neuromyelitis optica, or NMO. Finding antibodies to aquaporin-4 is indicative of NMO. But when Dr. Levy used aquaporin-4 reactive T cells, they could induce NMO in a mouse model, giving a clue to the role of T cells in the disease, and possibly opening up a new therapeutic avenue.
 
Interviewer – Dan Keller
What's different about this approach than what has been thought of previously?
 
Interviewee – Michael Levy
In neuromyelitis optica, there is the thought that the disease involves an antibody, the anti-aquaporin-4 antibody, that that antibody is involved in causing the disease. And what we demonstrated in this model is that we could recreate the disease simply by developing T cells against aquaporin-4. It's the exact same target as the antibody, but instead of using the antibody to exacerbate disease, we use T cells. And it works really well and causes optic neuritis and transverse myelitis, just like in the patient.
 
MSDF
Can you briefly describe your method?
 
Dr. Levy
We raised T cells in mice that don't have aquaporin-4. These mice see aquaporin-4 as a foreign antigen and mount an aggressive immune response against them, and we harvest those T cells from that animal. And what we do is we polarize them. We basically turn them into more aggressive types of immune cells in a dish. And then we transfer those T cells to a naïve mouse that does contain aquaporin-4. And those T cells attack the aquaporin-4, and it does so only in the optic nerves and the spinal cord and also a little bit in the brain.
 
MSDF
But aquaporin-4 is distributed more widely than that in the body.
 
Dr. Levy
That's correct. Actually, there's a higher level of aquaporin-4 in the lung, stomach, kidneys, muscle. Many tissues contain aquaporin-4, but the T cells decide which aquaporin-4 to attack. They are a thoughtful type of cell, and for whatever reason, and this is true in the human, too, the T cells only decide to go for those specific tissues.
 
MSDF
How does a mouse with aquaporin-4 get to an age where you can actually get these T cells out of it? What's the use of aquaporin-4 if they really can survive without it?
 
Dr. Levy
It's amazing that these knockout mice, they don't have any aquaporin-4, are completely viable. There are some abnormalities in function under certain stressful conditions, like stroke or brain trauma, but for the most part, they live normal lives. They must have a good compensatory mechanism that they don't need aquaporin-4, and that's fortunate for us because we can create these animal models.
 
MSDF
When you transferred these T cells to wild-type mice, what did you see?
 
Dr. Levy
Eight days after the transfer, the first thing we noticed is that the mice started blinking and the eyes became sunken into the head, and that's a sign of severe optic neuritis. And then two days later, they had a dragging tail. And a day after that, their hind limbs were paralyzed, and that indicated transverse myelitis.
 
MSDF
What's the role of the antibody if you can induce the disease with the T cell? And does the antibody in itself without T cells have an effect?
 
Dr. Levy
We looked at that, and what we found is that the antibody by itself has absolutely no effect. But in the context of a T cell attack, it can exacerbate the disease, and it does lend specificity to the pathology when you look at it under a microscope. If you add the antibody, there is more aquaporin-4 damage, and it recruits compliment, which causes that damage. So that's really the role of the antibody.
 
MSDF
Can you induce the antibody without T cells? Ess