Saturday, 22 April 2017

#ThinkSpeak: blinkered

What do you do when your neurologist knows best and says no? #ThinkSpeak #MSBlog

The other day an esteemed colleague, who is based in the US, contacted me as a co-author on the ocrelizumab in PPMS (Oratorio) study, to ask me 'how could I support the study's claim that ocrelizumab was effective in PPMS?'. He said the study was only positive because it was loaded with relapsing patients. The latter is based on the observation that approximately a quarter of subjects had Gd-enhancing lesions on their baseline scan.

I informed him that he was wrong for several reasons:

1. Firstly, the subjects in this study had PPMS. Anyone with a history of relapses was excluded.

2. It is not uncommon for pwPPMS to have Gd-enhancing lesions on MRI, particularly early in the course of their disease. I pointed out that the reason why a quarter of subjects had active baseline scans was that this was an early, and relatively young, population of PPMSers. The latter didn't occur by chance but by design. The study design was informed by the rituximab in PPMS trial, which showed that younger people with active MRIs were more likely to respond to treatment in a short period of time. To ignore this insight would have been folly.

3. I mentioned to him that the study was also positive across numerous secondary and tertiary endpoints, including objective MRI outcomes. Surely this meant the drug was working?

4. I explained to him my length-dependent axonopathy hypothesis and sent him our recent publication, which goes a long way to explaining the ORATORIO results. He said very interesting, but this didn't change his position.

5. I pointed out to him that although the treatment effect on EDSS and timed-25ft walk was relatively modest (~25% slowing of progression), the impact on upper limb function (9-HPT) was almost double (~45%). Wasn't ocrelizumab indicated on this observation alone? This particular individual is fully aware about how important hand function is for pwMS.

6. I also said that ocrelizumab worked in both cohorts of subjects, those with and without Gd-enhancing lesions at baseline. Although the results in these two subgroups were not statistically significant, the positive trends were obvious. It is important to realise the study was not powered to test a treatment effect in these two cohorts therefore we have to accept the overall results at face value. 

Despite my protestations he informed me that although all my points were interesting and valid he was not convinced by the science and therefore would not be offering ocrelizumab to his patients with PPMS. How do I respond to this? As I said last weekend neurologists are never wrong they can always justify their position from their own perspective. All I that I can hope is that pwPPMS under his care are informed and active. They need to arm themselves with knowledge and ask the right questions. If you aren't satisfied with the answers challenge them and ask some more questions. If you are still not satisfied you can always vote with your feet. 

This episode is deja vu. Almost the exact scenario played out in the UK when the interferons were launched for treating RRMS. Many neurologists would not accept that this class of drug was effective and hence were not offering them to their patients. Gradually things changed and most neurologists now accept that DMTs do modify the course of RRMS. I can only expect the same thing to happen with the treatment of more advanced MS (formerly know as progressive MS). Let's hope so for the sake of the thousands of PPMSers out there. 


Montalban et al. Ocrelizumab versus Placebo in Primary Progressive Multiple SclerosisN Engl J Med. 2017 Jan 19;376(3):209-220.

Background: An evolving understanding of the immunopathogenesis of multiple sclerosis suggests that depleting B cells could be useful for treatment. We studied ocrelizumab, a humanized monoclonal antibody that selectively depletes CD20-expressing B cells, in the primaryprogressive form of the disease. 

Methods: In this phase 3 trial, we randomly assigned 732 patients with primary progressive multiple sclerosis in a 2:1 ratio to receive intravenous ocrelizumab (600 mg) or placebo every 24 weeks for at least 120 weeks and until a prespecified number of confirmed disability progression events had occurred. The primary end point was the percentage of patients with disability progression confirmed at 12 weeks in a time-to-event analysis. 

Results: The percentage of patients with 12-week confirmed disability progression was 32.9% with ocrelizumab versus 39.3% with placebo (hazard ratio, 0.76; 95% confidence interval [CI], 0.59 to 0.98; P=0.03). The percentage of patients with 24-week confirmed disability progression was 29.6% with ocrelizumab versus 35.7% with placebo (hazard ratio, 0.75; 95% CI, 0.58 to 0.98; P=0.04). By week 120, performance on the timed 25-foot walk worsened by 38.9% with ocrelizumab versus 55.1% with placebo (P=0.04); the total volume of brain lesions on T2-weighted magnetic resonance imaging (MRI) decreased by 3.4% with ocrelizumab and increased by 7.4% with placebo (P<0.001); and the percentage of brain-volume loss was 0.90% with ocrelizumab versus 1.09% with placebo (P=0.02). There was no significant difference in the change in the Physical Component Summary score of the 36-Item Short-Form Health Survey. Infusion-related reactions, upper respiratory tract infections, and oral herpes infections were more frequent with ocrelizumab than with placebo. Neoplasms occurred in 2.3% of patients who received ocrelizumab and in 0.8% of patients who received placebo; there was no clinically significant difference between groups in the rates of serious adverse events and serious infections. 

Conclusions: Among patients with primary progressive multiple sclerosis, ocrelizumab was associated with lower rates of clinical and MRI progression than placebo. Extended observation is required to determine the long-term safety and efficacy of ocrelizumab. (Funded by F. Hoffmann-La Roche; ORATORIO ClinicalTrials.gov number, NCT01194570 .).

CoI: multiple

MS news maybe you will get access to fampridine

I was speaking to a pwMS and they told me that the company Acorda developing fampridine with Biogen has lost its patents in a court case, meaning that from 2018, generic fampridine may become available.

At present it has not got the NICE seal of approval and is not considered cost effective and so in many place you get no access.
Although there are surely a few more court battles to be had.

The price should drop and create greater access, but whilst checking this out, it seems the company has shed 20% of its staff.

So it is a business and a brutal business at that.
So it is about the bottom line

Potassium Channels as a major autoimmune target in MS, it ain't Kir 4.1

Zhong R1, Liang JTao AWu LYang XXu HHuang QZhuang SLong YGao C.
Anti-KIR4.1 Antibodies in Chinese Patients with Central Nervous System Inflammatory Demyelinating Disorders.

OBJECTIVES: The aim of this study was to explore the frequency of KIR4.1 antibodies in patients with multiple sclerosis (MS) and in control groups using a cell-based assay.
MATERIALS AND METHODS: A transfected HEK-293A cell line expressing KIR4.1 was established to test for the presence of KIR4.1 antibodies in blood serum. We tested 904 subjects, including 188 patients with MS, 264 patients with neuromyelitis optica spectrum disorders (NMOSD), 209 patients with other inflammatory neurologic disease (OIND), 203 patients with other noninflammatory neurological disease (OND), and 40 healthy controls.
RESULTS: KIR4.1 antibodies were present in 23 of the 188 (12.2%) MS patients, 42 of the 264 (15.9%) NMOSD patients, 32 of the 209 (15.3%) OIND patients, 24 of the 203 (11.8%) OND patients, and 2 of the 40 (5%) healthy controls. There were no significant differences among the MS and control groups (p = 0.279).
CONCLUSIONS:Anti-KIR4.1 antibody, as determined by a cell-based assay, is not a specific biomarker for MS


However we also have

Navas-Madroñal M, Valero-Mut A, Martínez-Zapata MJ, Simón-Talero MJ, Figueroa S, Vidal-Fernández N, López-Góngora M, Escartín A, Querol L. Absence of antibodies against KIR4.1 in multiple sclerosis: A three-technique approach and systematic review. PLoS One. 2017;12(4):e0175538.

INTRODUCTION: Antibodies targeting the inward-rectifying potassium channel KIR4.1 have been associated with multiple sclerosis (MS) but studies using diverse techniques have failed to replicate this association. The detection of these antibodies is challenging; KIR4.1 glycosylation patterns and the use of diverse technical approaches may account for the disparity of results. We aimed to replicate the association using three different approaches to overcome the technical limitations of a single technique. We also performed a systematic review to examine the association of anti-KIR4.1 antibodies with MS.
METHODS:Serum samples from patients with MS (n = 108) and controls (n = 77) were tested for the presence of anti-KIR4.1 antibodies using three methods: 1) by ELISA with the low-glycosylated fraction of recombinant KIR4.1 purified from transfected HEK293 cells according to original protocols; 2) by immunocytochemistry using KIR4.1-transfected HEK293 cells; and 3) by immunocytochemistry using the KIR4.1.-transfected MO3.13 oligodendrocyte cell line. We developed a systematic review and meta-analysis of the association of anti-KIR4.1 antibodies with MS according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.
RESULTS: We did not detect anti-KIR4.1 antibodies in the MS patients or in controls using ELISA. Neither did we detect any significant reactivity against the antigen on the cell surface using the KIR4.1-transfected HEK293 cells or the KIR4.1-transfected MO3.13 cells. We included 13 prospective controlled studies in the systematic review. Only three studies showed a positive association between anti-KIR4.1 and MS. Clinical and statistical heterogeneity between studies precluded meta-analysis of their results.
CONCLUSION:We found no association between anti-KIR4.1 antibody positivity and MS. Although this lack of replication may be due to technical limitations, evidence from our study and others is mounting against the role of KIR4.1 as a relevant MS autoantigen.


So one arguably paper in  a high impact factor journal spawned 15+ papers of which the majority (12 show the original claim  was incorrect that the majority of people do not have antibodies to channel. The is a common problem.

                                                                                   source Brain RNAseq

We have previously posted on the the relevance of potassium (K) channels to MS


ATP-sensitive inward rectifier potassium channel 10 is a protein that in humans is encoded by the KCNJ10 gene.

This has as a greater tendency to allow potassium to flow into, rather than out of, a cell. Kir4.1, may form a channel with other potassium channel protein and may be responsible for controlling potassium levels by glial cells in the brain. 

Humans with mutations in the KCNJ10 gene that cause loss of function in related K+ channels can display EpilepsyAtaxia, sensorineural deafness and tubulopathy of the kidney

A channel that is "inwardly-rectifying" is one that passes current (positive charge) more easily in the inward direction (into the cell) than in the outward direction (out of the cell). It is thought that this current may play an important role in regulating neuronal activity, by helping to stabilize the resting membrane potential of the cell.

At membrane potentials negative to potassium's reversal potential/Nernst potential (at the point when there is no ions moving across the membrane) inwardly rectifying K+ channels support the flow of positively charged K+ ions into the cell, pushing the membrane potential back to the resting potential, which is about -70mv. 


However, when the membrane potential is set positive to the channel's resting potential (e.g. +60 mV), these channels pass very little current. Simply put, this channel passes much more current in the inward direction than the outward one, at its operating voltage range. 

These channels are not perfect rectifiers, as they can pass some outward current in the voltage range up to about 30 mV above resting potential, which would occur when marked depolarisation happens.

Kir.4.1 was implicated as a target for autoantibodies antibodies in MS,  but as so often occurs these things are never replicated and indeed these studies, supports other studies and says the original idea that Potassium channels were a major cause of autoimmunity is clearly wrong. As reported previously.


Could antibodies directed to Kir4.1 cause problems? 
Absolutely as they react with astrocytes and oligodendrocytes, and so could block function or kill the cells


Neusch C, Rozengurt N, Jacobs RE, Lester HA, Kofuji P.
Kir4.1 potassium channel subunit is crucial for oligodendrocyte development and in vivo myelination. J Neurosci. 2001 ;21(15):5429-38. Kir4.1 forms the major K(+) conductance of oligodendrocytes and is therefore crucial for myelination. 


Potassium ions may therefore critical in myelination.

Bezine M, Debbabi M, Nury T, Ben-Khalifa R, Samadi M, Cherkaoui-Malki M, Vejux A, Raas Q, de Sèze J, Moreau T, El-Ayeb M, Lizard G. Evidence of K+ homeostasis disruption in cellular dysfunction triggered by 7-ketocholesterol, 24S-hydroxycholesterol, and tetracosanoic acid (C24:0) in 158N murine oligodendrocytes. Chem Phys Lipids. 2017. pii: S0009-3084(17)30011-7.

Imbalance in the homeostasis of K+ ions has been reported to contribute to the pathogenesis of neurodegenerative diseases. 7-ketocholesterol (7KC), 24S-hydroxycholesterol (24S-OHC) (this is oxidised cholesterol=oxysterols), and tetracosanoic acid (C24:0), often found at increased levels in patients with Multiple Sclerosis, are able to trigger numerous nerve cell dysfunctions......They induced [K+]i (potassium ion concentrations within the cell) and changes in lipid content and polarization of the cytoplasmic membrane. These events were associated with increased potassium ion concentrations...(and oligodendrocyte death). Blocking K channels with 4-AP (active ingredient of fampridine) exacerbated oligodenrocyte killing.

So lowering cholesterol should be good. Is this how statins work in progressive MS, by blocking oxysterols?
Too much potassium accumulating in a oligodendrocyte causes it to die. Interestingly 4-AP makes this worse.

Therefore, does fampridine kill off oligodendrocytes and block remyelination?

Bacia A, Wollmann R, Soliven B. K+ channel blockade impairs remyelination in the cuprizone model. Glia. 2004; 48(2):156-65.
We found that treatment with 4-aminopyridine (4-AP), a broad-spectrum K(+) channel antagonist, results in: (1) decreased number of oligodendroglial progenitors (OP) and OLGs; (2) diminished astrogliosis; and (3) decreased remyelination in the corpus callosum based on the immunoreactivity to myelin basic protein (MBP), Rip monoclonal antibody, and by electron microscopy.

However to counter that data in peripheral nerves indicate

Tseng KC, Li H, Clark A, Sundem L, Zuscik M, Noble M, Elfar J. 4-Aminopyridine promotes functional recovery and remyelination in acute peripheral nerve injury. EMBO Mol Med. 2016 ;8(12):1409-1420.


We know Fampridine allows nerves to work harder, improving walking speeds, but is this good news in the long term? 

Maybe it is time, that we saw data on slow release 4-AP improving remyelination in animal models and protecting nerves. 

Friday, 21 April 2017

#ResearchSpeak: why is there an increasing number of people with benign MS?

Do you have benign MS? If yes, why? #ResearchSpeak #MSBlog

The restrospective study below suggests the prevalence of benign MS is going up. This is good news and I suspect is due to many factors:

1. Ascertainment bias; diagnosing more people with MS who would not have been diagnosed in the past. This is driven by greater access to neurologists and imaging technology. Another factor is the 'Dr Google' effect. When you search online using a lot of non-specific symptoms MS often comes up on the list of possible causes prompting people to seek a neurological opinion. This is not a bad thing as it should lead to an earlier diagnosis.

2. Change in diagnostic criteria, which allows one to diagnosis MS earlier. This causes the so called Will Rogers phenomenon. "Will" Rogers (November 4, 1879 – August 15, 1935) was an American cowboy, performer, humorist, social commentator and motion picture actor. He was one of the world's best-known celebrities in the 1920s and 1930s. The Will Rogers phenomenon is obtained when moving an element from one set to another set raises the average values of both sets. It is based on the following quote, attributed (perhaps incorrectly) to Will Rogers: "When the Okies left Oklahoma and moved to California, they raised the average intelligence level in both states." The effect will occur when both of these conditions are met: (i) The element being moved is below average for its current set. Removing it will, by definition, raise the average of the remaining elements; (ii) the element being moved is above the current average of the set it is entering. Adding it to the new set will, by definition, raise the average.The paper by Sormani and colleagues has shown this very elegantly in the case of MS (Sormani et al. Will Rogers phenomenon in multiple sclerosis. Ann Neurol. 2008 Oct;64(4):428-33.).



The Will Rogers Phenomenon has occurred as the more active CISers are taken out of the CIS group and added to the MS group. This improves the outcome of both groups because the CISers left behind in the CIS group are more benign and it improves the MS group as the CISers that have been moved from CIS to MS are less active than the old MS group.


As a result of the Will Rogers Phenomenon we cannot use historical controls for MS trials. Each change in the diagnosis of MS alters the prognosis. Therefore in clinical trials we need contemporary placebo of control groups.

3. The effect of DMTs. Could it be that the treatment of MS is increasing the proportion of pwMS who fulfill the current definition of benign MS?


Sartori A, Abdoli M, Freedman MS. Can we predict benign multiple sclerosis? Results of a 20-year long-term follow-up study. J Neurol. 2017 Apr 17. doi: 10.1007/s00415-017-8487-y.

Background: Benign multiple sclerosis (MS) is a discussed clinical entity, with variable reported prevalence (6-64%) requiring at least 5-10 years of clinical observation. Moreover, many benign patients progress with time becoming no longer benign (NLB).

Objectives: The objective of this study is to compare benign MS patients (EDSS ≤3, 10 years from disease onset) who still fulfilled the definition at 20 years to those NLB.

Results: In our retrospective study based on Ottawa Hospital MS Clinic database, 175 benign patients fulfilled the inclusion criteria (clinically definite MS, EDSS ≤3 at 10 years, disease onset from 1983 to 1993, and clinical assessments performed at 10 ± 1 and 20 ± 1 years from onset). Out of the identified patients, 66.3% remained benign at 20 years; however, by changing the definition for benign to EDSS ≤2 or ≤1 at 10 years, they increased to 71.9 and 81.6%, respectively. Female sex, EDSS ≤1 at 10 years, and a pure sensory onset were associated with a benign course, while a pure motor onset with an NLB condition.

Conclusion: According to multivariate analysis, an EDSS ≤2 at 10 years predicted a long-term benign course. Our study questions the current definition of "benign" MS, suggesting a more stringent EDSS cutoff at 10 years to predict long-term benign prognosis.

MS and EBV

If EBV is the driver of MS, then there must surely be evidence that something related to EBV that associates with disease activity.

Does the Black Swan get it?

Gieß RM, Pfuhl C, Behrens JR, Rasche L, Freitag E, Khalighy N, Otto C, Wuerfel J, Brandt AU, Hofmann J, Eberspächer B, Bellmann-Strobl J, Paul F, Ruprecht K. Epstein-Barr virus antibodies in serum and DNA load in saliva are not associated with radiological or clinical disease activity in patients with early multiple sclerosis. PLoS One. 7;12(4):e0175279.

OBJECTIVE:

To investigate the association of Epstein-Barr virus (EBV) nuclear antigen-1 (EBNA-1) and viral capsid antigen (VCA) immunoglobulin (Ig)G antibodies in serum as well as EBV DNA load in saliva with radiological and clinical disease activity in patients with clinically isolated syndrome (CIS) and early relapsing-remitting MS (RRMS).

METHODS:

EBNA-1 and VCA immunoglobulin (Ig)G antibodies were determined in serum of 100 patients with CIS/early RRMS and 60 healthy controls. EBV DNA load was measured in saliva of 48 patients and 50 controls. Patients underwent clinical assessment with the Expanded Disability Status Scale (EDSS) and 3 Tesla magnetic resonance imaging at baseline and after a median of 20 months of follow-up (n = 63 for MRI, n = 71 for EDSS). The association of EBV parameters with occurrence of a second relapse, indicating conversion to clinically definite MS (CDMS), was evaluated over a median of 35 months of follow-up after the first clinical event (n = 89).

RESULTS:

EBNA-1 IgG antibody frequency (p = 0.00005) and EBNA-1 and VCA IgG antibody levels (p<0.0001 for both) were higher in patients than in controls. EBV DNA load in saliva did not differ between groups. Neither EBV antibody levels nor DNA load in saliva were associated with baseline or follow-up number or volume of T2-weighted (T2w) or contrast enhancing lesions, number of Barkhof criteria or the EDSS, or with the number of new T2w lesions, T2w lesion volume change or EDSS change on follow-up. Likewise, levels of EBV IgG antibodies in serum and DNA load in saliva were not associated with conversion to CDMS.

CONCLUSIONS:

While these findings confirm the association of EBV infection with early MS, neither EBNA-1 nor VCA IgG antibodies in serum nor EBV DNA load in saliva were associated with radiological or clinical disease activity in patients with CIS/early RRMS. These data are compatible with the concept that EBV may be a trigger for MS acting very early during the development of the disease.

Sisay S, Lopez-Lozano L, Mickunas M, Quiroga-Fernández A, Palace J, Warnes G, Lafuente RA, Dua P, Meier UC. Untreated relapsing remitting multiple sclerosis patients show antibody production against latent Epstein Barr Virus (EBV) antigens mainly in the periphery and innate immune IL-8 responses preferentially in the CNS. J Neuroimmunol. 2017 May 15;306:40-45.

BACKGROUND:Multiple sclerosis (MS) is an inflammatory and neurodegenerative disorder of the central nervous system (CNS). Reliable biomarkers are urgently needed for its diagnosis and management, and as clues to its pathogenesis, in which EBV is implicated.
OBJECTIVE:To measure IgG antibodies against EBV nuclear antigen-1 (EBNA-1) and innate inflammation status in paired serum and cerebrospinal fluid (CSF) samples from untreated relapsing-remitting MS (RRMS) patients.
MATERIALS AND METHODS:Anti-EBNA-1 IgG titres and IL-8, IL-1β, IL-6, IL-10, TNF-α and IL-12p70 cytokine levels were measured in 20 untreated RRMS-patients and 17 healthy controls.
RESULTS:We found higher serum anti-EBNA-1 IgG and IL-8 levels in RRMS-patients than in healthy controls. Interestingly, levels of IL-8 - relative to total protein - were much higher in the CSF, whereas the anti-EBNA-1 antibodies were significantly higher in the sera. More detailed analysis showed that anti-EBNA-1 antibodies relative to total IgG were also higher in the serum in the majority of RRMS patients compared to CSF. Levels of anti-EBNA-1 IgG and IL-8 showed a strong correlation between serum and CSF.
CONCLUSION:These findings in newly diagnosed RRMS-patients imply anti-EBNA-1 antibody production mainly in the periphery and innate immune responses preferentially in the CNS. Both their potential as disease biomarkers and their implications for the pathogenesis of MS warrant further investigation.

So both studies agree that there is evidence of EBV infection in people diagnosed with MS. So the Black swan lives. 

However, no evidence of viral shedding in saliva and clinical activity was found, but not sure why this would be the casse even if EBV was the driver for attacks.