Temporal Relationship Between Serum Neurofilament Light Chain and Radiologic Disease Activity in Patients With Multiple Sclerosis

BACKGROUND AND OBJECTIVES

Serum neurofilament light chain (sNfL) levels correlate with multiple sclerosis (MS) disease activity, but the dynamics of this correlation are unknown. We evaluated the relationship between sNfL levels and radiologic MS disease activity through monthly assessments during the 24-week natalizumab treatment interruption period in RESTORE (NCT01071083).

METHODS

In the RESTORE trial, participants with relapsing forms of MS who had received natalizumab for ≥12 months were randomized to either continue or stop natalizumab and followed with MRI and blood draws every 4 weeks to week 28 and again at week 52 The sNfL was measured, and its dynamics were correlated with the development of gadolinium-enhancing (Gd+) lesions. Log-linear trend in sNfL levels were modeled longitudinally using generalized estimating equations with robust variance estimator from baseline to week 28.

RESULTS

Of 175 patients enrolled in RESTORE, 166 had serum samples for analysis. Participants with Gd+ lesions were younger (37.7 vs 43.1, p = 0.001) and had lower Expanded Disability Status Scale scores at baseline (2.7 vs 3.4, p = 0.017) than participants without Gd+ lesions. sNfL levels increased in participants with Gd+ lesions (n = 65) compared with those without (n = 101, mean change from baseline to maximum sNfL value, 12.1 vs 3.2 pg/mL, respectively; p = 0.003). As the number of Gd+ lesions increased, peak median sNfL change also increased by 1.4, 3.0, 4.3, and 19.6 pg/mL in the Gd+ lesion groups of 1 (n = 12), 2-3 (n = 18), 4-9 (n = 21), and ≥10 (n = 14) lesions, respectively. However, 46 of 65 (71%) participants with Gd+ lesions did not increase above the 95th percentile threshold of the group without Gd+ lesions. The initial increase of sNfL typically trailed the first observation of Gd+ lesions, and the peak increase in sNfL was a median [interquartile range] of 8 [0, 12] weeks after the first appearance of the Gd+ lesion.

DISCUSSION

Although sNfL correlated with the presence of Gd+ lesions, most participants with Gd+ lesions did not have elevations in sNfL levels. These observations have implications for the use and interpretation of sNfL as a biomarker for monitoring MS disease activity in controlled trials and clinical practice.

A review of Bruton's tyrosine kinase inhibitors in multiple sclerosis

Bruton's tyrosine kinase (BTK) inhibitors are an emerging class of therapeutics in multiple sclerosis (MS). BTK is expressed in B-cells and myeloid cells, key progenitors of which include dendritic cells, microglia and macrophages, integral effectors of MS pathogenesis, along with mast cells, establishing the relevance of BTK inhibitors to diverse autoimmune conditions. First-generation BTK inhibitors are currently utilized in the treatment of B-cell malignancies and show efficacy in B-cell modulation. B-cell depleting therapies have shown success as disease-modifying treatments (DMTs) in MS, highlighting the potential of BTK inhibitors for this indication; however, first-generation BTK inhibitors exhibit a challenging safety profile that is unsuitable for chronic use, as required for MS DMTs. A second generation of highly selective BTK inhibitors has shown efficacy in modulating MS-relevant mechanisms of pathogenesis in preclinical as well as clinical studies. Six of these BTK inhibitors are undergoing clinical development for MS, three of which are also under investigation for chronic spontaneous urticaria (CSU), rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Phase II trials of selected BTK inhibitors for MS showed reductions in new gadolinium-enhancing lesions on magnetic resonance imaging scans; however, the safety profile is yet to be ascertained in chronic use. Understanding of the safety profile is developing by combining safety insights from the ongoing phase II and III trials of second-generation BTK inhibitors for MS, CSU, RA and SLE. This narrative review investigates the potential of BTK inhibitors as an MS DMT, the improved selectivity of second-generation inhibitors, comparative safety insights established thus far through clinical development programmes and proposed implications in female reproductive health and in long-term administration.

Immunomodulatory potential of anti-IFN-beta antibodies on monocyte-derived macrophages

Introduction: Multiple sclerosis (MS) is a disabling neurological disease with an unknown etiology, where the recombinant interferon beta (rIFNβ) is the most established treatment. However, the development of anti-IFNβ antibodies has posed a significant therapeutic drawback. In this study, the interaction between anti-IFNβ antibodies and macrophages was investigated to assess the effects on the immune system. Methodology: Using magnetic beads, anti-IFNβ antibodies were extracted from MS patients' sera positive for anti-IFNβ antibodies. A negative control (antibody-negative situation) and a baseline control were obtained in parallel. Bead or extracted beadantibody complexes were then incubated vitro with monocyte-derived human macrophages. After incubation, macrophage cultures were tested for 91 immunologically relevant gene expressions by RT-PCR. Results and Discussions: A Gene expression difference between antibody positive and negative situations was hypothesized to reflect the direct effects between antibodies and macrophages. Thus, 37-39 genes were either up-regulated or downregulated due to this direct interaction. Of these, only 2-4 genes were up-regulated, and the rest were down-regulated. These observations suggest that anti-IFNβ antibodies have an overall suppressive effect on immunologically relevant gene activity when antibodies interact with macrophages. Conclusion: The fate and effects of circulating anti-IFNβ antibodies are mainly unknown. With the observations obtained at in vitro level, such effects, especially from an immunological point of view, are suppressive on immunocompetent cells such as macrophages. However, in vivo verification is necessary.

Fatigue, depression, and product tolerability during long-term treatment with intravenous immunoglobulin (Gamunex® 10%) in patients with chronic inflammatory demyelinating polyneuropathy

INTRODUCTION/AIMS

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is characterized by progressive weakness and sensory loss, often affecting patient's ability to walk and perform activities of daily living independently. Furthermore, patients often report fatigue and depression which can affect their quality of life. These symptoms were assessed in CIDP patients receiving long-term intravenous immunoglobulin (IVIG) treatment.

METHODS

GAMEDIS was a multi-center, prospective, non-interventional study in adult CIDP patients treated with IVIG (10%) and followed for two years. Inflammatory Neuropathy Cause and Treatment (INCAT) disability score, Hughes Disability Scale (HDS), Fatigue Severity Scale (FSS), Beck Depression Inventory II (BDI), Short Form-36 health survey (SF-36) and Work Productivity and Activity Impairment Score Attributable to General Health (WPAI-GH) were assessed at baseline and quarterly. Dosing and treatment intervals, changes in outcome parameters, and adverse events (AEs) were analyzed.

RESULTS

148 evaluable patients were followed for a mean of 83.3 weeks. The mean maintenance IVIG dose was 0.9 g/kg/cycle (mean cycle interval 38 days). Disability and fatigue remained stable throughout the study. Mean INCAT score: 2.4 ± 1.8 at baseline and 2.5 ± 1.9 at study end. HDS: 74.3% healthy/minor symptoms at baseline and 71.6% at study end. Mean FSS: 4.2 ± 1.6 at baseline and 4.1 ± 1.7 at study end. All patients reported minimal/no depression at baseline and throughout. SF-36 and WPAI-GH scores remained stable. Fifteen patients (9.5%) experienced potentially treatment-related AEs. There were no AEs in 99.3% of infusions.

DISCUSSION

Long-term treatment of CIDP patients with IVIG 10% in real-world conditions maintained clinical stability on fatigue and depression over 96 weeks. This treatment was well-tolerated and safe.

Safety experience with continued exposure to ofatumumab in patients with relapsing forms of multiple sclerosis for up to 3.5 years

Background:

Ofatumumab is approved for the treatment of relapsing multiple sclerosis (RMS). Ongoing safety reporting is crucial to understand its long-term benefit–risk profile.

Objective:

Report the safety and tolerability of ofatumumab in RMS after extended treatment up to 3.5 years.

Methods:

Patients completing ASCLEPIOS I/II (phase 3), APLIOS, or APOLITOS (phase 2) trials could enter ALITHIOS, a phase 3b, open-label, long-term safety study. We analyzed cumulative data of continuous ofatumumab treatment and of patients newly switched from teriflunomide.

Results:

The safety population had 1969 patients: 1292 continuously treated with ofatumumab (median time-at-risk 35.5 months, 3253 patient-years) and 677 newly switched (median time-at-risk 18.3 months, 986 patient-years). A total of 1650 patients (83.8%) had ⩾1 adverse events and 191 (9.7%) had ⩾1 serious adverse events. No opportunistic infections or progressive multifocal leukoencephalopathy events were identified; the risk of malignancies was low. Mean serum immunoglobulin (Ig) G levels remained stable. Mean IgM levels decreased but remained above the lower limit of normal in most. Serious infection incidence was low; decreased Ig levels were not associated with serious infections.

Conclusion:

In patients with up to 3.5 years’ exposure, ofatumumab was well tolerated, with no new safety risks identified. These findings, with its established effectiveness, support a favorable benefit–risk profile of ofatumumab in RMS.

OUP accepted manuscript

Patients with multiple sclerosis acquire disability either through relapse-associated worsening (RAW) or progression independent of relapse activity (PIRA). This study addresses the relative contribution of relapses to disability worsening over the course of the disease, how early progression begins and the extent to which multiple sclerosis therapies delay disability accumulation.

Using the Novartis-Oxford multiple sclerosis (NO.MS) data pool spanning all multiple sclerosis phenotypes and paediatric multiple sclerosis, we evaluated ∼200 000 Expanded Disability Status Scale (EDSS) transitions from >27 000 patients with ≤15 years follow-up. We analysed three datasets: (i) A full analysis dataset containing all observational and randomized controlled clinical trials in which disability and relapses were assessed (n = 27 328); (ii) all phase 3 clinical trials (n = 8346); and (iii) all placebo-controlled phase 3 clinical trials (n = 4970). We determined the relative importance of RAW and PIRA, investigated the role of relapses on all-cause disability worsening using Andersen-Gill models and observed the impact of the mechanism of worsening and disease-modifying therapies on the time to reach milestone disability levels using time continuous Markov models.

PIRA started early in the disease process, occurred in all phenotypes and became the principal driver of disability accumulation in the progressive phase of the disease. Relapses significantly increased the hazard of all-cause disability worsening events; following a year in which relapses occurred (versus a year without relapses), the hazard increased by 31–48% (all P < 0.001). Pre-existing disability and older age were the principal risk factors for incomplete relapse recovery. For placebo-treated patients with minimal disability (EDSS 1), it took 8.95 years until increased limitation in walking ability (EDSS 4) and 18.48 years to require walking assistance (EDSS 6). Treating patients with disease-modifying therapies delayed these times significantly by 3.51 years (95% confidence limit: 3.19, 3.96) and 3.09 years (2.60, 3.72), respectively. In patients with relapsing-remitting multiple sclerosis, those who worsened exclusively due to RAW events took a similar length of time to reach milestone EDSS values compared with those with PIRA events; the fastest transitions were observed in patients with PIRA and superimposed relapses.

Our data confirm that relapses contribute to the accumulation of disability, primarily early in multiple sclerosis. PIRA begins in relapsing-remitting multiple sclerosis and becomes the dominant driver of disability accumulation as the disease evolves. Pre-existing disability and older age are the principal risk factors for further disability accumulation. The use of disease-modifying therapies delays disability accrual by years, with the potential to gain time being highest in the earliest stages of multiple sclerosis.

Population Pharmacokinetic-B Cell Modeling for Ofatumumab in Patients with Relapsing Multiple Sclerosis

BACKGROUND

Ofatumumab, a fully human anti-CD20 monoclonal antibody indicated for the treatment of relapsing forms of multiple sclerosis (RMS), binds to a unique conformational epitope, thereby depleting B cells very efficiently and allowing subcutaneous administration at lower doses.

OBJECTIVES

The aims were to characterize the relationship between ofatumumab concentration and B cell levels, including the effect of covariates such as body weight, age, or baseline B cell count, and use simulations to confirm the chosen therapeutic dose.

METHODS

Graphical and regression analyses previously performed based on data from a dose-range finding study provided the B cell depletion target used in the present work. All available adult phase 2/3 data for ofatumumab in RMS patients were pooled to develop a population pharmacokinetics (PK)-B cell count model, using nonlinear mixed-effects modeling. The population PK-B cell model was used to simulate B cell depletion and repletion times and the effect of covariates on PK and B cell metrics, as well as the dose response across a range of subcutaneous ofatumumab monthly doses.

RESULTS

The final PK-B cell model was developed using data from 1486 patients. The predetermined B cell target was best achieved and sustained with the 20-mg dose regimen, with median B cell count reaching 8 cells/µL in 11 days and negligible repletion between doses. Only weight had a significant effect on PK, which did not translate into any clinically relevant effect on B cell levels.

CONCLUSION

The PK-B cell modeling confirms the dose chosen for the licensed ofatumumab regimen and demonstrates no requirement for dose adjustment based on adult patient characteristics.

Effect of ofatumumab versus placebo in relapsing multiple sclerosis patients from Japan and Russia: Phase 2 APOLITOS study

BACKGROUND

Ofatumumab, the first fully human anti-CD20 monoclonal antibody, has been developed as a treatment for relapsing multiple sclerosis (RMS) which can be self-administered at home.

OBJECTIVE

To investigate the efficacy and safety of ofatumumab in RMS patients from Japan and Russia.

METHODS

APOLITOS included a 24-week, double-blind, placebo-controlled core-part followed by an open-label extension-part. Patients were randomized (2:1) to subcutaneous ofatumumab 20 mg or placebo. Primary outcome was the number of gadolinium-enhancing (Gd+) T1 lesions per scan over 24 weeks.

RESULTS

Sixty-four patients were randomized (ofatumumab, n = 43; placebo, n = 21). Primary endpoint was met; ofatumumab reduced Gd + T1 lesions versus placebo by 93.6% (p < 0.001) and the results were consistent across regions (Japan/Russia). Ofatumumab reduced annualized T2 lesion and relapse rate versus placebo by week 24. Both groups showed benefit from ofatumumab in the extension-part. Incidence of adverse events was lower with ofatumumab versus placebo (69.8% vs 81.0%); injection-related reactions were most common. No deaths, opportunistic infections, or malignancies were reported.

CONCLUSION

Ofatumumab demonstrated superior efficacy versus placebo, with sustained effect through 48 weeks in RMS patients from Japan/Russia. Switching to ofatumumab after 24 weeks led to rapid radiological and clinical benefits. Safety findings were consistent with pivotal trials.

Corneal confocal microscopy differentiates inflammatory from diabetic neuropathy

BACKGROUND

Immune-mediated neuropathies, such as chronic inflammatory demyelinating polyneuropathy (CIDP) are treatable neuropathies. Among individuals with diabetic neuropathy, it remains a challenge to identify those individuals who develop CIDP. Corneal confocal microscopy (CCM) has been shown to detect corneal nerve fiber loss and cellular infiltrates in the sub-basal layer of the cornea. The objective of the study was to determine whether CCM can distinguish diabetic neuropathy from CIDP and whether CCM can detect CIDP in persons with coexisting diabetes.

METHODS

In this multicenter, case-control study, participants with CIDP (n = 55) with (n = 10) and without (n = 45) diabetes; participants with diabetes (n = 58) with (n = 28) and without (n = 30) diabetic neuropathy, and healthy controls (n = 58) underwent CCM. Corneal nerve fiber density (CNFD), corneal nerve fiber length (CNFL), corneal nerve branch density (CNBD), and dendritic and non-dendritic cell density, with or without nerve fiber contact were quantified.

RESULTS

Dendritic cell density in proximity to corneal nerve fibers was significantly higher in participants with CIDP with and without diabetes compared to participants with diabetic neuropathy and controls. CNFD, CNFL, and CNBD were equally reduced in participants with CIDP, diabetic neuropathy, and CIDP with diabetes.

CONCLUSIONS

An increase in dendritic cell density identifies persons with CIDP. CCM may, therefore, be useful to differentiate inflammatory from non-inflammatory diabetic neuropathy.

Temporal profile of serum neurofilament light in multiple sclerosis: Implications for patient monitoring

Objective:

To understand how longitudinal serum neurofilament light chain (sNfL) patterns can inform its use as a prognostic biomarker in multiple sclerosis (MS) and evaluate whether sNfL reflects MS disease activity and disease-modifying therapy usage.

Methods:

This was a post hoc analysis of longitudinal data and samples from the ADVANCE trial (NCT00906399) of patients with relapsing–remitting MS (RRMS). sNfL was measured every 3 months for 2 years, then every 6 months for 4 years. Regression models explored how sNfL data predicted 4-year values of brain volume, expanded disability status scale score, and T2 lesions. sNfL levels were assessed in those receiving placebo, peginterferon beta-1a, and those with disease activity.

Results:

Baseline sNfL was a predictor of 4-year brain atrophy and development of new T2 lesions. Clinical (p = 0.02) and magnetic resonance imaging (MRI) (p < 0.01) outcomes improved in those receiving peginterferon beta-1a whose sNfL decreased to <16 pg/mL after 12 months versus those whose sNfL remained ⩾16 pg/mL. Mean sNfL levels decreased in peginterferon beta-1a-treated patients and increased in placebo-treated patients (–9.5% vs. 6.8%; p < 0.01). sNfL was higher and more variable in patients with evidence of active MS.

Conclusion:

These data support sNfL as a prognostic and disease-monitoring biomarker for RRMS.

Association of Serum Neurofilament Light Levels With Long-term Brain Atrophy in Patients With a First Multiple Sclerosis Episode

IMPORTANCE

Data are needed on the potential long-term prognostic association of serum neurofilament light in multiple sclerosis (MS).

OBJECTIVE

To evaluate serum neurofilament light as a biomarker associated with long-term disease outcomes in clinically isolated syndrome.

DESIGN, SETTING, AND PARTICIPANTS

This post hoc cohort study used data from the Controlled High-Risk Avonex Multiple Sclerosis Prevention Study, a 36-month, multicenter, placebo-controlled interferon β-1a randomized clinical trial conducted from April 1996 to March 2000, and its long-term (5- and 10-year) extension study from February 2001 to March 2009. Participants included individuals with a symptomatic initial demyelinating event and brain magnetic resonance imaging (MRI) lesions suggestive of MS. Data were analyzed from April 2017 through 2019.

EXPOSURE

The variable of interest was naturally occurring serum neurofilament light concentration.

MAIN OUTCOMES AND MEASURES

Gadolinium-enhancing (Gd+) lesion number, T2 lesion volume, and brain parenchymal fraction, a measure of brain atrophy were measured at baseline and 5 and 10 years. Multivariate regression models evaluated whether age, sex, and baseline covariates, including serum neurofilament light, brain parenchymal fraction, Expanded Disability Status Scale, Gd+ lesion count, and T2 lesion volume, were associated with brain parenchymal fraction changes over 5 and 10 years.

RESULTS

Among 308 included participants (mean [SD] age, 33.2 [7.6] years; 234 [76.0%] women), baseline serum neurofilament light concentrations were associated with Gd+ lesions (Spearman r = 0.41; P < .001) and T2 lesion volume (Spearman r = 0.42; P < .001). Among covariates for brain parenchymal fraction change, serum neurofilament light concentration had the greatest correlation with change in brain parenchymal fraction at 5 years (Spearman r = -0.38; P < .001) and was the only variable associated with brain parenchymal fraction at 10 years (Spearman r = -0.45; P < .001). Participants in the highest vs lowest baseline serum neurofilament light tertiles showed brain parenchymal fraction reduction at 5 years (-1.83% [95% CI, -1.49% to -2.18%] vs -0.95% [95% CI, -0.78% to -1.12%]; P < .001) and 10 years (-3.54% [95% CI, -2.90% to -4.17%] vs -1.90% [95% CI, -1.43% to -2.37%]; P < .001). At 5 years, 6 of 45 participants (13.3%) in the highest neurofilament tertile and 2 of 52 participants (3.8%) in the lowest neurofilament tertile achieved an Expanded Disability Status Scale score of 3.5 or greater.

CONCLUSIONS AND RELEVANCE

This cohort study found that higher baseline serum neurofilament light levels were associated with increased brain atrophy over 5 and 10 years. These findings suggest that serum neurofilament light could be a biomarker associated with disease severity stratification in early MS and may help to guide intervention.

NK cell markers predict the efficacy of IV immunoglobulins in CIDP

Objective

To assess whether IV immunoglobulins (IVIgs) as a first-line treatment for chronic inflammatory demyelinating polyneuropathy (CIDP) have a regulative effect on natural killer (NK) cells that is related to clinical responsiveness to IVIg.

Methods

In a prospective longitudinal study, we collected blood samples of 29 patients with CIDP before and after initiation of IVIg treatment for up to 6 months. We used semiquantitative PCR and flow cytometry in the peripheral blood to analyze the effects of IVIg on the NK cells. The results were correlated with clinical aspects encompassing responsiveness.

Results

We found a reduction in the expression of several typical NK cell genes 1 day after IVIg administration. Flow cytometry furthermore revealed a reduced cytotoxic CD56^dim NK cell population, whereas regulatory CD56^bright NK cells remained mostly unaffected or were even increased after IVIg treatment. Surprisingly, the observed effects on NK cells almost exclusively occurred in IVIg-responsive patients with CIDP.

Conclusions

The correlation between the altered NK cell population and treatment efficiency suggests a crucial role for NK cells in the still speculative mode of action of IVIg treatment. Analyzing NK cell subsets after 24 hours of treatment initiation appeared as a predictive marker for IVIg responsiveness. Further studies are warranted investigating the potential of NK cell status as a routine parameter in patients with CIDP before IVIg therapy.

Classification of evidence

This study provides Class I evidence that NK cell markers predict clinical response to IVIg in patients with CIDP.

Corneal Confocal Microscopy Demonstrates Corneal Nerve Loss in Patients With Trigeminal Neuralgia

Background: The diagnosis of trigeminal neuralgia (TN) is challenging due to the lack of objective diagnostics. Corneal confocal microscopy (CCM) is a non-invasive ophthalmic imaging technique, which allows quantification of corneal nerve fibers arising from the trigeminal ganglion and may allow the assessment of neurodegeneration in TN. Methods: CCM was undertaken in 11 patients with TN and 11 age-matched healthy controls. Corneal nerve fiber density (CNFD), corneal nerve branch density, corneal nerve fiber length (CNFL), corneal nerve fiber width, corneal nerve fiber area, and dendritic cell and non-dendritic cell density with or without nerve fiber contact were quantified. Results: Patients with TN had significantly lower CNFD and CNFL but no difference for any other corneal nerve or dendritic cell parameter in the ipsilateral and the contralateral cornea compared to the control group. There was no significant difference in corneal nerve and cell parameters between patients with TN with and without involvement of the ophthalmic nerve (V1) or with nerve vessel conflict. Conclusion: Corneal confocal microscopy is a rapid non-invasive imaging technique that identifies symmetrical corneal nerve loss in patients with TN.

Harnessing Real-World Data to Inform Decision-Making: Multiple Sclerosis Partners Advancing Technology and Health Solutions (MS PATHS)

Background: Multiple Sclerosis Partners Advancing Technology and Health Solutions (MS PATHS) is the first example of a learning health system in multiple sclerosis (MS). This paper describes the initial implementation of MS PATHS and initial patient characteristics.

Methods: MS PATHS is an ongoing initiative conducted in 10 healthcare institutions in three countries, each contributing standardized information acquired during routine care. Institutional participation required the following: active MS patient census of ≥500, at least one Siemens 3T magnetic resonance imaging scanner, and willingness to standardize patient assessments, share standardized data for research, and offer universal enrolment to capture a representative sample. The eligible participants have diagnosis of MS, including clinically isolated syndrome, and consent for sharing pseudonymized data for research. MS PATHS incorporates a self-administered patient assessment tool, the Multiple Sclerosis Performance Test, to collect a structured history, patient-reported outcomes, and quantitative testing of cognition, vision, dexterity, and walking speed. Brain magnetic resonance imaging is acquired using standardized acquisition sequences on Siemens 3T scanners. Quantitative measures of brain volume and lesion load are obtained. Using a separate consent, the patients contribute DNA, RNA, and serum for future research. The clinicians retain complete autonomy in using MS PATHS data in patient care. A shared governance model ensures transparent data and sample access for research.

Results: As of August 5, 2019, MS PATHS enrolment included participants (n = 16,568) with broad ranges of disease subtypes, duration, and severity. Overall, 14,643 (88.4%) participants contributed data at one or more time points. The average patient contributed 15.6 person-months of follow-up (95% CI: 15.5–15.8); overall, 166,158 person-months of follow-up have been accumulated. Those with relapsing–remitting MS demonstrated more demographic heterogeneity than the participants in six randomized phase 3 MS treatment trials. Across sites, a significant variation was observed in the follow-up frequency and the patterns of disease-modifying therapy use.

Conclusions: Through digital health technology, it is feasible to collect standardized, quantitative, and interpretable data from each patient in busy MS practices, facilitating the merger of research and patient care. This approach holds promise for data-driven clinical decisions and accelerated systematic learning.

Blood neurofilament light levels segregate treatment effects in multiple sclerosis

Objective

To determine factors (including the role of specific disease modulatory treatments [DMTs]) associated with (1) baseline, (2) on-treatment, and (3) change (from treatment start to on-treatment assessment) in plasma neurofilament light chain (pNfL) concentrations in relapsing-remitting multiple sclerosis (RRMS).

Methods

Data including blood samples analyses and long-term clinical follow-up information for 1,261 Swedish patients with RRMS starting novel DMTs were analyzed using linear regressions to model pNfL and changes in pNfL concentrations as a function of clinical variables and DMTs (alemtuzumab, dimethyl fumarate, fingolimod, natalizumab, rituximab, and teriflunomide).

Results

The baseline pNfL concentration was positively associated with relapse rate, Expanded Disability Status Scale score, Age-Related MS Severity Score, and MS Impact Score (MSIS-29), and negatively associated with Symbol Digit Modalities Test performance and the number of previously used DMTs. All analyses, which used inverse propensity score weighting to correct for differences in baseline factors at DMT start, highlighted that both the reduction in pNfL concentration from baseline to on-treatment measurement and the on-treatment pNfL level differed across DMTs. Patients starting alemtuzumab displayed the highest reduction in pNfL concentration and lowest on-treatment pNfL concentrations, while those starting teriflunomide had the smallest decrease and highest on-treatment levels, but also starting from lower values. Both on-treatment pNfL and decrease in pNfL concentrations were highly dependent on baseline concentrations.

Conclusion

Choice of DMT in RRMS is significantly associated with degree of reduction in pNfL, which supports a role for pNfL as a drug response marker.

Predicting disability progression in multiple sclerosis: Insights from advanced statistical modeling

Background:

There is an unmet need for precise methods estimating disease prognosis in multiple sclerosis (MS).

Objective:

Using advanced statistical modeling, we assessed the prognostic value of various clinical measures for disability progression.

Methods:

Advanced models to assess baseline prognostic factors for disability progression over 2 years were applied to a pooled sample of patients from placebo arms in four different phase III clinical trials. least absolute shrinkage and selection operator (LASSO) and ridge regression, elastic nets, support vector machines, and unconditional and conditional random forests were applied to model time to clinical disability progression confirmed at 24 weeks. Sensitivity analyses for different definitions of a combined endpoint were carried out, and bootstrap was used to assess prediction model performance.

Results:

A total of 1582 patients were included, of which 434 (27.4%) had disability progression in a combined endpoint over 2 years. Overall model discrimination performance was relatively poor (all C-indices ⩽ 0.65) across all models and across different definitions of progression.

Conclusion:

Inconsistency of prognostic factor importance ranking confirmed the relatively poor prediction ability of baseline factors in modeling disease progression in MS. Our findings underline the importance to explore alternative predictors as well as alternative definitions of commonly used endpoints.

Neurofilament light levels are associated with long-term outcomes in multiple sclerosis

Background:

Neurofilament light chain (NfL) is a promising marker of disease activity/treatment response in multiple sclerosis (MS), although its predictive value for long-term clinical outcomes remains unclear.

Objective:

We measured NfL from a phase 3 trial in relapsing-remitting MS and investigated its association with outcomes after 8 and 15 years.

Methods:

NfL concentrations were measured by single molecule array assay in cerebrospinal fluid (CSF) from MS patients (n = 235) in a 2-year randomized clinical trial (RCT) of intramuscular interferon β-1a, and in serum (n = 164) from the extension study.

Results:

Year 2 CSF and Year 3 serum NfL were associated with brain parenchymal fraction (BPF) change over 8 years (p < 0.0001, r = −0.46; p < 0.05. r = −0.36, respectively) and were predictive of reaching Expanded Disability Status Scale (EDSS) ⩾ 6.0 at Year 8 (odds ratio (OR) (upper vs lower tertile) = 3.4; 95% confidence interval (CI) = 1.2–9.9, p < 0.05; OR = 11.0, 95% CI = 2.0–114.6; p < 0.01, respectively). Serum NfL concentration (Year 4) was predictive of reaching EDSS score ⩾6.0 at 15 years (OR (upper vs lower tertile) = 4.9; 95% CI = 1.4–20.4; p < 0.05). NfL concentrations were complementary to 2-year BPF change in predicting long-term outcomes.

Conclusion:

Serum and CSF NfL concentrations were associated with long-term clinical outcomes in MS patients and are promising biomarkers for disease severity stratification supporting treatment decisions.

A proof-of-concept application of a novel scoring approach for personalized medicine in multiple sclerosis

BACKGROUND

Stratified medicine methodologies based on subgroup analyses are often insufficiently powered. More powerful personalized medicine approaches are based on continuous scores.

OBJECTIVE

We deployed a patient-specific continuous score predicting treatment response in patients with relapsing-remitting multiple sclerosis (RRMS).

METHODS

Data from two independent randomized controlled trials (RCTs) were used to build and validate an individual treatment response (ITR) score, regressing annualized relapse rates (ARRs) on a set of baseline predictors.

RESULTS

The ITR score for the combined treatment groups versus placebo detected differential clinical response in both RCTs. High responders in one RCT had a cross-validated ARR ratio of 0.29 (95% confidence interval (CI) = 0.13-0.55) versus 0.62 (95% CI = 0.47-0.83) for all other responders (heterogeneity p = 0.038) and were validated in the other RCT, with the corresponding ARR ratios of 0.31 (95% CI = 0.18-0.56) and 0.61 (95% CI = 0.47-0.79; heterogeneity p = 0.036). The strongest treatment effect modifiers were the Short Form-36 Physical Component Summary, age, Visual Function Test 2.5%, prior MS treatment and Expanded Disability Status Scale.

CONCLUSION

Our modelling strategy detects and validates an ITR score and opens up avenues for building treatment response calculators that are also applicable in routine clinical practice.

Trapped in the epineurium: early entry into the endoneurium is restricted to neuritogenic T cells in experimental autoimmune neuritis

Background

Autoimmune polyneuropathies are acquired inflammatory disorders of the peripheral nervous system (PNS) characterized by inflammation, demyelination, and axonal degeneration. Although the pathogenesis has not been fully elucidated, T cells recognizing self-antigens are believed to initiate inflammation in a subgroup of patients. However, the route and time of T cell entry into the PNS have not yet been described in detail. In this study, we analyzed both kinetics as well as localization of retrovirally transfected green fluorescent protein (GFP)-expressing neuritogenic T lymphocytes in experimental autoimmune neuritis (EAN).

Methods

T lymphocytes obtained from rats following EAN induction by immunization with peripheral nerve protein peptide P2_55–78 were retrovirally engineered to express GFP. Non-specific T cells were negatively selected by in vitro restimulation, whereas GFP-expressing neuritogenic T cells (reactive to P2_55–78) were adoptively transferred into healthy rats (AT-EAN). Antigen-specific T cell tracking and localization was performed by flow cytometry and immunohistochemistry during the course of disease.

Results

After induction of autoimmune neuritis, P2-reactive T cells were detectable in the liver, spleen, lymph nodes, lung, peripheral blood, and the sciatic nerves with distinct kinetics. A significant number of GFP⁺ T cells appeared early in the lung with a peak at day four. In the peripheral nerves within the first days, GFP-negative T cells rapidly accumulated and exceeded the number of GFP-expressing cells, but did not enter the endoneurium. Very early after adoptive transfer, T cells are found in proximity to peripheral nerves and in the epineurium. However, only GFP-expressing neuritogenic T cells are able to enter the endoneurium from day five after transfer.

Conclusions

Our findings suggest that neuritogenic T cells invade the PNS early in the course of disease. However, neuritogenic T cells cross the blood-nerve barrier with a certain delay without preference to dorsal roots. Further understanding of the pathophysiological role of autoagressive T cells may help to improve therapeutic strategies in immune-mediated neuropathies.

Novel pathomechanisms in inflammatory neuropathies

Inflammatory neuropathies are rare autoimmune-mediated disorders affecting the peripheral nervous system. Considerable progress has recently been made in understanding pathomechanisms of these disorders which will be essential for developing novel diagnostic and therapeutic strategies in the future. Here, we summarize our current understanding of antigenic targets and the relevance of new immunological concepts for inflammatory neuropathies. In addition, we provide an overview of available animal models of acute and chronic variants and how new diagnostic tools such as magnetic resonance imaging and novel therapeutic candidates will benefit patients with inflammatory neuropathies in the future. This review thus illustrates the gap between pre-clinical and clinical findings and aims to outline future directions of development.

Schwann cells promote post-traumatic nerve inflammation and neuropathic pain through MHC class II

The activation of T helper cells requires antigens to be exposed on the surface of antigen presenting cells (APCs) via MHC class II (MHC-II) molecules. Expression of MHC-II is generally limited to professional APCs, but other cell types can express MHC-II under inflammatory conditions. However, the importance of these conditional APCs is unknown. We and others have previously shown that Schwann cells are potentially conditional APCs, but the functional relevance of MHC-II expression by Schwann cells has not been studied in vivo. Here, we conditionally deleted the MHC-II β-chain from myelinating Schwann cells in mice and investigated how this influenced post-traumatic intraneural inflammation and neuropathic pain using the chronic constriction injury (CCI) model. We demonstrate that deletion of MHC-II in myelinating Schwann cells reduces thermal hyperalgesia and, to a lesser extent, also diminishes mechanical allodynia in CCI in female mice. This was accompanied by a reduction of intraneural CD4+ T cells and greater preservation of preferentially large-caliber axons. Activation of T helper cells by MHC-II on Schwann cells thus promotes post-traumatic axonal loss and neuropathic pain. Hence, we provide experimental evidence that Schwann cells gain antigen-presenting function in vivo and modulate local immune responses and diseases in the peripheral nerves.

Development and Validation of an Enzyme-Linked Immunosorbent Assay for the Detection of Binding Anti-Drug Antibodies against Interferon Beta

Objective

To develop and validate a method for the detection of binding anti-drug antibodies (ADAs) against interferon beta (IFN-β) in human serum as part of a European initiative (ABIRISK) aimed at the prediction and analysis of clinical relevance of anti-biopharmaceutical immunization to minimize the risk.

Method

A two-tiered bridging enzyme-linked immunosorbent assay (ELISA) format was selected and validated according to current recommendations. Screening assay: ADA in serum samples form complexes with immobilized IFN-β and biotinylated IFN-β, which are then detected using HRP labeled Streptavidin and TMB substrate. Confirmation assay: Screen “putative positive” samples are tested in the presence of excess drug (preincubation of sera with 0.3 µg/mL of soluble IFN-β) and percentage of inhibition is calculated.

Results

The assay is precise, and the sensitivity of the assay was confirmed to be 26 ng/mL using commercially available polyclonal rabbit antihuman IFN-β in human sera as the positive control.

Conclusion

An ultrasensitive ELISA for IFN-β-binding ADA testing has been validated. This will form the basis to assess anti-biopharmaceutical immunization toward IFN-β with regards to its clinical relevance and may allow for the development of predictive tools, key aims within the ABIRISK consortium.

Peginterferon beta-1a improves MRI measures and increases the proportion of patients with no evidence of disease activity in relapsing-remitting multiple sclerosis: 2-year results from the ADVANCE randomized controlled trial

BACKGROUND

Subcutaneous peginterferon beta-1a has previously been shown to reduce the number of T2-hyperintense and gadolinium-enhancing (Gd+) lesions over 2 years in patients with relapsing-remitting multiple sclerosis (RRMS), and to reduce T1-hypointense lesion formation and the proportion of patients showing evidence of disease activity, based on both clinical and radiological measures, compared with placebo over 1 year of treatment. The objectives of the current analyses were to evaluate T1 lesions and other magnetic resonance imaging (MRI) measures, including whole brain volume and magnetization transfer ratio (MTR) of normal appearing brain tissue (NABT), and the proportions of patients with no evidence of disease activity (NEDA), over 2 years.

METHODS

Patients enrolled in the ADVANCE study received continuous peginterferon beta-1a every 2 or 4 weeks for 2 years, or delayed treatment (placebo in Year 1; peginterferon beta-1a every 2 or 4 weeks in Year 2). MRI scans were performed at baseline and Weeks 24, 48, and 96. Proportions of patients with NEDA were calculated based on radiological criteria (absence of Gd + and new/newly-enlarging T2 lesions) and clinical criteria (no relapse or confirmed disability progression) separately and overall.

RESULTS

Peginterferon beta-1a every 2 weeks significantly reduced the number and volume of T1-hypointense lesions compared with delayed treatment over 2 years. Changes in whole brain volume and MTR of NABT were suggestive of pseudoatrophy during the first 6 months of peginterferon beta-1a treatment, which subsequently began to resolve. Significantly more patients in the peginterferon beta-1a every 2 weeks group compared with the delayed treatment group met MRI-NEDA criteria (41% vs 21%; odds ratio [OR] 2.56; p < 0.0001), clinical-NEDA criteria (71% vs 57%; OR 1.90; p < 0.0001) and achieved overall-NEDA (37% vs 16%; OR 3.09; p < 0.0001).

CONCLUSION

Peginterferon beta-1a provides significant improvements in MRI measures and offers patients a good chance of remaining free from evidence of MRI, clinical and overall disease activity over a sustained 2-year period.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00906399 ; Registered on: May 20, 2009.

Peginterferon beta-1a reduces disability worsening in relapsing-remitting multiple sclerosis: 2-year results from ADVANCE

BACKGROUND

In the pivotal phase III 2-year ADVANCE study, subcutaneous peginterferon beta-1a 125 mcg every 2 weeks demonstrated significant improvements in clinical outcomes, including disability endpoints, in patients with relapsing-remitting multiple sclerosis (RRMS). Here, we aim to further evaluate disability data from ADVANCE, and explore associations between confirmed disability progression (CDP), functional status, and health-related quality of life (HRQoL).

METHODS

In total, 1512 patients were randomized to placebo or peginterferon beta-1a 125 mcg every 2 or 4 weeks. After 1 year, patients on placebo were re-randomized to peginterferon beta-1a every 2 or 4 weeks. CDP was defined as ⩾1.0 point increase from a baseline Expanded Disability Status Scale (EDSS) score ⩾ 1.0, or ⩾1.5-point increase from baseline 0, confirmed 12 or 24 weeks after onset.

RESULTS

Peginterferon beta-1a every 2 weeks significantly reduced risk of 12- and 24-week CDP at 1 year compared with placebo (12-week CDP: 6.8% versus 10.5%, p = 0.038; 24-week CDP: 4% versus 8.4%, p = 0.0069, peginterferon beta-1a every 2 weeks versus placebo, respectively). Benefits were maintained over 2 years (11.2% and 7.7%, peginterferon beta-1a every 2 weeks in 12- and 24-week CDP, respectively). Approximately 90% of patients with 24-week CDP had simultaneous worsening by ⩾1 point in at least one functional system score, most commonly pyramidal. Displaying a 24-week CDP was associated with worse scores on the Multiple Sclerosis Functional Composite (MSFC) scale and several HRQoL instruments; the impact of CDP was attenuated by treatment with peginterferon beta-1a every 2 weeks.

CONCLUSIONS

Peginterferon beta-1a has the potential to prevent/delay worsening of disability in patients with relapsing-remitting multiple sclerosis. Furthermore, improved benefits in disability status with peginterferon beta-1a were also associated with improved functional status and HRQoL [ClinicalTrials.gov identifier: NCT00906399].

Improvement in relapse recovery with peginterferon beta-1a in patients with multiple sclerosis

Background

Subcutaneous peginterferon beta-1a every 2 weeks significantly affects clinical outcomes in patients with relapsing–remitting multiple sclerosis (RRMS).

Objectives

To explore relationships between relapses and worsening of disability in patients with RRMS, and assess the treatment effect of peginterferon beta-1a on relapse recovery.

Methods

Post-hoc analysis of the 2-year, randomized, double-blind, parallel-group, Phase 3 ADVANCE study. The severity of relapses, proportion of patients with relapses associated with residual disability (onset of 24-week confirmed disability progression (CDP) within 90 days following a relapse), and persistence of changes in Functional Systems Scores, were compared between treatment groups.

Results

Subcutaneous peginterferon beta-1a every 2 weeks significantly reduced the proportion of patients experiencing relapse associated with CDP over 2 years (6.6%, compared with 15.1% of patients who received placebo in Year 1; p = 0.02). Reduction in relapses associated with residual disability was greater than the treatment effect on overall relapse rate, and occurred despite similar relapse severity across treatment groups.

Conclusions

The beneficial effect of peginterferon beta-1a on risk of CDP may be attributable to the combination of an overall reduction in the risk of relapses and improvement in recovery from relapses, thus limiting further disability progression.

Trial registration

ClinicalTrials.gov identifier: NCT00906399

Incidence, characterization, and clinical impact analysis of peginterferon beta1a immunogenicity in patients with multiple sclerosis in the ADVANCE trial

BACKGROUND

Efficacy of interferon beta in multiple sclerosis (MS) can be dampened in patients who develop neutralizing antidrug antibodies (NAbs). Peginterferon beta1a is an interferon conjugated with a polyethylene glycol (PEG) moiety. Pegylation increases a drug's half life and exposure, and may also reduce immunogenicity.

OBJECTIVE

The objective of this study was to characterize the incidence and impact of immunogenicity to peginterferon beta1a over 2 years in patients with MS.

METHODS

Patients with relapsing-remitting MS (N = 1512) were randomized to subcutaneous peginterferon beta1a 125 μg every 2 or 4 weeks, or placebo, for 1 year; patients in the placebo group were rerandomized to active treatment in year 2. The incidence and titers of binding antibodies (BAbs) and NAbs to interferon and antibodies to PEG (anti-PEG) were assessed in analytically validated assays. The clinical impact of immunogenicity on relapse and magnetic resonance imaging endpoints was evaluated.

RESULTS

Over 2 years, 6%, less than 1%, and 7% of patients developed anti-interferon BAbs, NAbs, and anti-PEG antibodies, respectively. There was no discernible clinically meaningful effect of antibody status on the pharmacodynamic, efficacy, or safety parameters evaluated, although these analyses were limited by the low incidence of treatment-emergent antibodies.

CONCLUSION

The treatment effect of peginterferon beta1a in patients with relapsing-remitting MS is not expected to be attenuated by immunogenicity.

Subgroup and sensitivity analyses of annualized relapse rate over 2 years in the ADVANCE trial of peginterferon beta-1a in patients with relapsing-remitting multiple sclerosis

ADVANCE was a 2-year, double-blind, placebo-controlled, Phase 3 study in 1512 patients aged 18–65 years with relapsing-remitting multiple sclerosis, which demonstrated that peginterferon beta-1a 125 mcg administered subcutaneously every 2 or 4 weeks led to significant reductions in annualized relapse rate (ARR) compared with placebo. This analysis examined ARR over 2 years in ADVANCE across subgroups. Patients were treated with peginterferon beta-1a every 2 weeks or every 4 weeks, or placebo during Year 1. Thereafter, patients on placebo were re-randomized to peginterferon beta-1a every 2 weeks or every 4 weeks (delayed treatment). Subgroup analyses were conducted by demographics and baseline disease characteristics. The following results compared ARR in these subgroups for patients in continuous 2-week treatment versus continuous 4-week treatment. ARR was similar in most demographic and baseline disease characteristic subgroups evaluated within the peginterferon beta-1a every-2-week arm or every-4-week arm over 2 years. Although for both doses some differences in the point estimates for ARR were noted among the subgroups, considerable overlap in the confidence intervals suggested that the efficacy of peginterferon beta-1a is similar in all patients irrespective of gender, age, body weight, geographical region, and disease activity at initiation of treatment. Within each peginterferon beta-1a dosing group, ARR was generally similar across most subgroups.

Oral Tolerance Induction in Experimental Autoimmune Encephalomyelitis with Candida utilis Expressing the Immunogenic MOG35-55 Peptide

Multiple sclerosis (MS) is an autoimmune disease that attacks myelinated axons in the central nervous system. Induction of oral tolerance is a potent mechanism to prevent autoimmunity. The food yeast Candida utilis was used to test the therapeutic potential of oral tolerance induction in an animal model of human multiple sclerosis (MS). We constructed a C. utilis strain, which displays a fusion peptide composed of the encephalitogenic MOG35-55 peptide and the C. utilis Gas1 cell wall protein on its surface.By immunizing mice with MOG35-55 peptide experimental autoimmune encephalomyelitis (EAE) was induced in a mouse model. Feeding of mice with C. utilis that expresses MOG35-55 peptide on its surface was started seven days prior to immunization and was continued for ten days. Control animals were treated with wild-type fungus or left untreated. Untreated mice developed first clinical symptoms ten days post immunization (p. i.) with an ascending paralysis reaching maximal clinical disability at day 18 to 20 p. i.. Treatment with the wild-type strain demonstrated comparable clinical symptoms. In contrast, oral gavage of MOG35-55-presenting fungus ameliorated the development of EAE. In addition, incidence as well as maximal clinical disease severity were significantly reduced. Interestingly, reduction of disease severity also occurred in animals treated with heat-inactivated C. utilis cells indicating that tolerance induction was independent of fungal viability. Better disease outcome correlated with reduced demyelination and cellular inflammation in the spinal cord, lower T cell proliferation against rechallenge with MOG35-55 and more regulatory T cells in the lymph nodes. Our data demonstrate successful that using the food approved fungus C. utilis presenting the immunogenic MOG35-55 peptide on its surface induced an oral tolerance against this epitope in EAE. Further studies will reveal the nature and extent of an anti-inflammatory environment established by the treatment that prevents the development of an autoimmune disorder affecting the CNS.

Fatigue, Pain, Anxiety and Depression in Guillain-Barré Syndrome and Chronic Inflammatory Demyelinating Polyradiculoneuropathy

BACKGROUND

In the clinical evaluation of patients with Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), scant attention is paid to symptoms such as fatigue, pain and anxiety/depression. We aimed at addressing seminal studies that focused on the burden of these symptoms and their impact on quality of life (QoL) in these conditions.

SUMMARY

Fatigue, pain, and anxiety/depression are increasingly being recognized in patients with GBS and CIDP, although their pathophysiological provenance remains unknown. Fatigue and pain are significant in terms of prevalence and intensity, may be a presenting symptom, and can persist for years after apparent functional recovery, suggesting residual injury. Anxiety/depression has also been examined although studies are limited. Despite their negative impact on QoL, the long-term dynamics of these symptoms in patients with GBS and particularly CIDP receiving therapy in routine clinical practice have not been systematically evaluated. Such observations formed the basis for the ongoing (GAMEDIS) studies evaluating the effect of Gamunex on fatigue and depression in patients with CIDP, of which some preliminary data are presented.

KEY MESSAGES

Strength and sensory deficits are the main areas of focus in patients with GBS and CIDP, but they do not explain the total reduction in QoL, suggesting the possible role of other complaints. A more comprehensive approach to patient care demands that factors such as pain, fatigue and anxiety/depression receive greater attention. The non-interventional GAMEDIS studies are expected to provide valuable insight into the long-term effectiveness of Gamunex in everyday practice.

Subcutaneous immunoglobulins in the treatment of chronic immune-mediated neuropathies

Intravenous immunoglobulins represent an established therapy for the treatment of chronic immune-mediated neuropathies, specifically chronic inflammatory demyelinating polyradiculoneuropathies (CIDPs) as well as multifocal motor neuropathies (MMNs). For the treatment of antibody deficiency syndromes, subcutaneous immunoglobulins (SCIgs) have represented a mainstay for decades. An emerging body of evidence suggests that SCIg might also exhibit clinical efficacy in CIDP and MMN. This article reviews the current evidence for clinical effectiveness, as well as safety of SCIg for the treatment of immune-mediated neuropathies, and addresses remaining open questions in this context. We conclude that despite the need for controlled long-term studies to demonstrate long-term efficacy of SCIg in immune-mediated neuropathies, SCIg may already represent a potential therapeutic alternative for selected patients.

Corneal confocal microscopy in chronic inflammatory demyelinating polyneuropathy

Objective

There is an unmet need for better diagnostic tools to further delineate clinical subsets of heterogeneous chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and multifocal motor neuropathy (MMN) to facilitate treatment decisions. Corneal confocal microscopy (CCM) is a noninvasive and reproducible nerve imaging technique. This study evaluates the potential of CCM as a diagnostic surrogate in CIDP and MMN.

Methods

In a cross‐sectional prospective approach, 182 patients and healthy controls were studied using CCM to quantify corneal nerve damage and immune cell infiltration.

Results

Patients with CIDP and MMN had a reduction in corneal nerve fiber (CNF) measures and an increase in corneal immune cell infiltrates. In CIDP, CNF parameters decreased with increasing duration of disease. The number of dendritic cells in proximity to CNFs was increased in patients with early disease and correlated with the degree of motor affection. A further reduction in CNF parameters and an increase in nondendritic cells were observed in patients with painful neuropathy. In CIDP patients with antineuronal antibodies the number of nondendritic cells was increased.

Interpretation

Our findings suggest that CNF loss may reflect severity of neuropathy and quantification of distinct cells around the CNF plexus may help in stratifying CIDP subtypes, clinical course, and disease activity. However, further longitudinal studies are required before CCM can be considered as a valid surrogate endpoint for patients with CIDP and MMN.

Dimethyl fumarate in relapsing-remitting multiple sclerosis: rationale, mechanisms of action, pharmacokinetics, efficacy and safety

Dimethyl fumarate (DMF), a fumaric acid ester, is a new orally available disease-modifying agent that was recently approved by the US FDA and the EMA for the management of relapsing forms of multiple sclerosis (MS). Fumaric acid has been used for the management of psoriasis, for more than 50 years. Because of the known anti-inflammatory properties of fumaric acid ester, DMF was brought into clinical development in MS. More recently, neuroprotective and myelin-protective mechanism actions have been proposed, making it a possible candidate for MS treatment. Two Phase III clinical trials (DEFINE, CONFIRM) have evaluated the safety and efficacy of DMF in patients with relapsing-remitting MS. Being an orally available agent with a favorable safety profile, it has become one of the most commonly prescribed disease-modifying agents in the USA and Europe.

Safety and Clinical Outcomes of Rituximab Treatment in Patients with Multiple Sclerosis and Neuromyelitis Optica: Experience from a National Online Registry (GRAID)

INTRODUCTION

Multiple sclerosis (MS) is an immune-mediated disease. Over the last decades therapeutic options have broadened tremendously. Nevertheless, various therapeutic agents, e.g., rituximab, are currently used in the treatment of MS off label. Disease or health registries are useful methods to collect information about off-label treatments. The German registry for autoimmune disease (GRAID) is a multicenter, retrospective, non-interventional database of patients with various autoimmune diseases.

AIM/METHODS

The aim of this observational analysis is to present safety data of rituximab in the treatment of MS and neuromyelitis optica (NMO) in a real life clinical setting based on the available registry data.

RESULTS

Data were collected nationwide in patients who received rituximab. 56 patients were treated with rituximab for MS or NMO. Average observation period was 9.6 months (SD 7.6, ranging from 6 to 29.7 months). Interval between treatments cycles differed tremendously (ranging from 0 to 21 months, median 10 months). Number of infusions ranged from 1 up to more than 8. The analysis provides experience on almost 50 patient years. Infusion related reactions were most common and reported in four patients; infections were seen in three patients (two of them were hospitalized for urinary tract infection and urosepsis). All patients recovered from infection. Full treatment response was attested in a quarter of the patients; two thirds benefited partially from treatment.

DISCUSSION

Safety data of almost 50 patient years of treatment with rituximab show that rituximab is tolerated well in MS/NMO patients. Infections and infusion reactions are the most common adverse events. Our data may help the individual physician to balance efficacy of rituximab against the risk. • Data on rituximab in MS and NMO are provided for almost 50 patientyears • Rituximab was tolerated well • No unexpected side effects were seen • Almost 80% of the patients benefited at least partially from treatment.

Successful Replication of GWAS Hits for Multiple Sclerosis in 10,000 Germans Using the Exome Array

Genome-wide association studies (GWAS) successfully identified various chromosomal regions to be associated with multiple sclerosis (MS). The primary aim of this study was to replicate reported associations from GWAS using an exome array in a large German study. German MS cases (n = 4,476) and German controls (n = 5,714) were genotyped using the Illumina HumanExome v1-Chip. Genotype calling was performed with the Illumina Genome Studio(TM) Genotyping Module, followed by zCall. Single-nucleotide polymorphisms (SNPs) in seven regions outside the human leukocyte antigen (HLA) region showed genome-wide significant associations with MS (P values < 5 × 10(-8) ). These associations have been reported previously. In addition, SNPs in three previously reported regions outside the HLA region yielded P values < 10(-5) . The effect of nine SNPs in the HLA region remained (P < 10(-5) ) after adjustment for other significant SNPs in the HLA region. All of these findings have been reported before or are driven by known risk loci. In summary, findings from previous GWAS for MS could be successfully replicated. We conclude that the regions identified in previous GWAS are also associated in the German population. This reassures the need for detailed investigations of the functional mechanisms underlying the replicated associations.

A 10-year follow-up of the European multicenter trial of interferon β-1b in secondary-progressive multiple sclerosis

OBJECTIVES

To explore long-term effects of treatment and prognostic relevance of variables assessed at baseline and during the European secondary progressive multiple sclerosis (SPMS) trial of interferon beta 1b (IFNB-1b).

METHODS

We assessed 362 patients (60% female; median age 41 years; Expanded Disability Status Scale (EDSS): 5.5; 51% randomized to IFNB-1b) for their EDSS and treatment history after 10 years. Non-parametric analysis of covariance (ANCOVA) and multivariate linear regression models were applied.

RESULTS

Median EDSS was 6.0 at the end of the randomized controlled trial (RCT), in the IFNB-1b and placebo groups, and 7.0 in long-term follow-up patients (those receiving IFNB-1b in the RCT were 6.5 and those receiving placebo in the RCT were 7.0; p = 0.086). 24 patients (6.6%) were deceased. The EDSS at baseline and the EDSS change during the RCT were the most important predictors of the EDSS 10 years later (partial R(2): 0.47). The ability to predict changes in EDSS 10 years after the RCT was limited (R(2): 0.12). Magnetic resonance imaging (MRI) measures remained in the predictive models, but explained < 5% of the variability.

CONCLUSIONS

The results from this analysis did not provide convincing evidence to support a favorable long-term outcome in those patients allocated IFNB-1b during the RCT, in our SPMS cohort. The progressive stage of the disease remains largely unpredictable by clinical and conventional MRI measures, so better prognostic markers are needed.

Isoniazid-induced polyneuropathy in a tuberculosis patient - implication for individual risk stratification with genotyping?

BACKGROUND

Development of polyneuropathy (PNP) under treatment for tuberculosis (TB), including isoniazid (INH), is a highly relevant adverse drug effect. The NAT2 acetylation status is a predictor of potential toxic effects of INH. The question as to whether individual risk stratification by genotyping is useful to avoid suffering of patients and to lower costs for the health care system is of considerable clinical importance.

CASE PRESENTATION

After drug treatment for TB, including INH, a 23-year-old man developed severe PNP. During the treatment, laboratory results have been indicating incipient liver and renal injury. Later, molecular genetic analyses were performed and revealed a variation in the NAT2 gene and the c1/c2 genotype of the CYP2E1 gene, both described to contribute to an elevated risk for anti-tuberculostatic-induced liver damages (ATIL).

CONCLUSION

The combination of metabolizer genotypes should be taken into account as a cause for toxic effects and the development of PNP. Individual genotyping, performed before medication or at least if an elevation of liver parameters is observed, may reduce the risk of severe cases of PNP by early adjustment of treatment. Our case study indicates that evaluation of individual risk stratification with systematic pharmacogenetic genotyping of metabolizer gene combinations in the context of TB treatment should be addressed in clinical studies with larger cohorts.

Emerging tumefactive multiple sclerosis after switching therapy from natalizumab to fingolimod

In this report we describe a multiple sclerosis patient who developed a relapse with magnetic resonance imaging (MRI) features of tumefactive demyelination after switching therapy from natalizumab to fingolimod. Tumefactive lesions emerged 16 weeks after stopping natalizumab and eight weeks after commencing fingolimod therapy but had been absent at the time of diagnosis and throughout the preceding course of the disease. Thus, the first-time occurrence of atypical lesion features may have been caused by the change in immunotherapy. The possible relevance of natalizumab withdrawal vs fingolimod introduction is discussed against the background of recently published case studies.

Conversion from clinically isolated syndrome to multiple sclerosis: A large multicentre study

Background and objective:

We explored which clinical and biochemical variables predict conversion from clinically isolated syndrome (CIS) to clinically definite multiple sclerosis (CDMS) in a large international cohort.

Methods:

Thirty-three centres provided serum samples from 1047 CIS cases with at least two years’ follow-up. Age, sex, clinical presentation, T2-hyperintense lesions, cerebrospinal fluid (CSF) oligoclonal bands (OCBs), CSF IgG index, CSF cell count, serum 25-hydroxyvitamin D3 (25-OH-D), cotinine and IgG titres against Epstein-Barr nuclear antigen 1 (EBNA-1) and cytomegalovirus were tested for association with risk of CDMS.

Results:

At median follow-up of 4.31 years, 623 CIS cases converted to CDMS. Predictors of conversion in multivariable analyses were OCB (HR = 2.18, 95% CI = 1.71–2.77, p < 0.001), number of T2 lesions (two to nine lesions vs 0/1 lesions: HR = 1.97, 95% CI = 1.52–2.55, p < 0.001; >9 lesions vs 0/1 lesions: HR = 2.74, 95% CI = 2.04–3.68, p < 0.001) and age at CIS (HR per year inversely increase = 0.98, 95% CI = 0.98–0.99, p < 0.001). Lower 25-OH-D levels were associated with CDMS in univariable analysis, but this was attenuated in the multivariable model. OCB positivity was associated with higher EBNA-1 IgG titres.

Conclusions:

We validated MRI lesion load, OCB and age at CIS as the strongest independent predictors of conversion to CDMS in this multicentre setting. A role for vitamin D is suggested but requires further investigation.

Fingolimod treatment promotes regulatory phenotype and function of B cells

OBJECTIVE

To evaluate the influence of Fingolimod treatment on B-cell subset composition and function in multiple sclerosis patients and its potential clinical relevance.

METHODS

Subset composition and cytokine production of B cells derived from peripheral blood mononuclear cells from multiple sclerosis patients under Fingolimod treatment, untreated multiple sclerosis patients and healthy controls were analyzed by flow cytometry and ELISA. Migration of lymphocyte subsets across primary human brain microvascular endothelial cells was assessed in an in vitro transmigration assay. Cell numbers and composition of B-cell subsets in cerebrospinal fluid and peripheral blood were determined by flow cytometry. Regulatory B-cell frequencies were correlated with parameters of disease stability.

RESULTS

Within the peripheral B-cell compartment of Fingolimod-treated patients, the proportion of regulatory B cells (CD38(+)CD27(-)CD24(+)CD5(+)) was significantly increased as compared to treatment-naïve multiple sclerosis patients and to healthy controls, and significantly more regulatory B cells produced Interleukin-10. Fingolimod treatment enhanced the capacity of regulatory B cells to transmigrate across brain endothelial cells in an in vitro model of the blood-brain-barrier. In line with these findings, the cerebrospinal fluid/blood ratio of total B cells and regulatory B cells was strongly increased by Fingolimod treatment, and patients exhibited increased regulatory B-cell frequencies in the cerebrospinal fluid. Finally, elevated regulatory B-cell percentages in the periphery significantly correlated with clinical and paraclinical disease stability.

INTERPRETATION

These data suggest a novel and as yet unrecognized role of Fingolimod in correction of the imbalance between regulatory and effector B-cell functions in multiple sclerosis both by direct effects and indirect partitioning effects on B-cell subpopulations.