Brain atrophy after immunoablation and stem cell transplantation in multiple sclerosis

The current standing of autologous haematopoietic stem cell transplantation for the treatment of multiple sclerosis

Autologous haematopoietic stem cell transplantation (aHSCT) is gaining traction as a valuable treatment option for patients affected by severe multiple sclerosis (MS), particularly the relapsing–remitting form. We describe the current literature in terms of clinical trials, observational and retrospective studies, as well as immune reconstitution following transplantation, with a focus on the conditioning regimens used for transplantation. The evidence base predominantly consists of non-randomised, uncontrolled clinical trials or data from retrospective or observational cohorts, i.e. very few randomised or controlled trials. Most often, intermediate-intensity conditioning regimens are used, with promising results from both myeloablative and lymphoablative strategies, as well as from regimens that are low and high intensity. Efficacy of transplantation, which is likely secondary to immune reconstitution and restored immune tolerance, is, therefore, not clearly dependent on the intensity of the conditioning regimen. However, the conditioning regimen may well influence the immune response to transplantation. Heterogeneity of conditioning regimens among studies hinders synthesis of the articles assessing post-aHSCT immune system changes. Factors associated with better outcomes were lower Kurtzke Expanded Disability Status Scale, relapsing–remitting MS, younger age, and shorter disease duration at baseline, which supports the guidance for patient selection proposed by the European Society for Blood and Marrow Transplantation. Interestingly, promising outcomes were described for patients with secondary progressive MS by some studies, which may be worth taking into account when considering treatment options for patients with active, progressive disease. Of note, a significant proportion of patients develop autoimmune disease following transplantation, with alemtuzumab-containing regimens associated with the highest incidence.

Autologous Hematopoietic Stem Cell Transplantation in Multiple Sclerosis Patients: Monocentric Case Series and Systematic Review of the Literature

Multiple sclerosis (MS) is a chronic, inflammatory and immune-mediated disease of the central nervous system (CNS), commonly affecting young adults and potentially associated with life-long disability. About 14 disease-modifying treatments (DMTs) are currently approved for the treatment of MS. However, despite the use of highly effective therapies, some patients exhibit a highly active disease with an aggressive course from onset and a higher risk of long-term disability accrual. In the last few years, several retrospective studies, clinical trials, meta-analyses and systematic reviews have investigated autologous hematopoietic stem cell transplantation (AHSCT) as a possible therapeutic option in order to address this unmet clinical need. These studies demonstrated that AHSCT is a highly efficacious and relatively safe therapeutic option for the treatment of highly active MS. Particularly, over recent years, the amount of evidence has grown, with significant improvements in the development of patient selection criteria, choice of the most suitable transplant technique and clinical experience. In this paper, we present six patients who received AHSCT in our MS center and we systematically reviewed recent evidence about the long-term efficacy and safety of AHSCT and the placement of AHSCT in the rapidly evolving therapeutic armamentarium for MS.

Brain volume change after high-dose immunosuppression and autologous hematopoietic cell transplantation for relapsing-remitting multiple sclerosis

BACKGROUND

Brain volume loss (BVL) is commonly observed after high-dose immunosuppression and autologous hematopoietic cell transplantation (HDIT/HCT) for treatment of multiple sclerosis (MS). To better understand the mechanisms of underlying BVL associated with this treatment, we characterized the time courses of whole-brain (WB), grey-matter (GM) and white-matter (WM) volume loss in relapsing-remitting MS (RRMS) patients who received BEAM-based HDIT/HCT.

METHODS

We used Jacobian integration to measure MRI-based WB, GM and WM volume changes up to 5 years after transplant in twenty-four RRMS participants who underwent BEAM-based HDIT/HCT. Using a two-piecewise mixed-effects model, we estimated the short-term (baseline to 1 year) and long-term (beyond 1 year) rates of BVL after HDIT/HCT. We also compared the rates based on the presence of gadolinium-enhancing lesions at baseline, and the maintenance of event-free survival during follow-up.

RESULTS

On average, accelerated short-term BVL of -1.37% (SE: 0.21), -0.86% (SE: 0.28) and -2.18% (SE: 0.26) occurred in WB, GM and WM, respectively. Baseline T1-weighted MRI WM lesion volume was a significant predictor in the WB (short-term) and the WM (short-term and long-term). The average rates of BVL after the initial acceleration were -0.22%/y (SE: 0.10), -0.13%/y (SE: 0.11) and -0.36%/y (SE: 0.11) in the WB, GM and WM, respectively. Participants with gadolinium-enhancing lesions at baseline had significantly higher short-term rates of GM (-1.56% vs. -0.27%, p = 0.01) and WB volume loss (-1.94% vs. -0.81%, p = 0.006) at 1 year follow-up as compared to those without gadolinium-enhancing lesions. WM volume loss was not significantly different (-2.59% vs. -1.66%, p = 0.16). Participants who maintained event-free survival had similar rates of BVL compared to those who did not.

CONCLUSIONS

BVL may accelerate for months after HDIT/HCT. However, over the long-term, adequate HDIT/HCT may reduce BVL rates to those similar to normal aging at the WB level.

Dynamics of pseudo-atrophy in RRMS reveals predominant gray matter compartmentalization

Objective

To assess the dynamics of “pseudo‐atrophy,” the accelerated brain volume loss observed after initiation of anti‐inflammatory therapies, in patients with multiple sclerosis (MS).

Methods

Monthly magnetic resonance imaging (MRI) data of patients from the IMPROVE clinical study (NCT00441103) comparing relapsing‐remitting MS patients treated with interferon beta‐1a (IFNβ‐1a) for 40 weeks versus those receiving placebo (16 weeks) and then IFNβ‐1a (24 weeks) were used to assess percentage of gray (PGMVC) and white matter (PWMVC) volume changes. Comparisons of PGMVC and PWMVC slopes were performed with a mixed effect linear model. In the IFNβ‐1a‐treated arm, a quadratic term was included in the model to evaluate the plateauing effect over 40 weeks.

Results

Up to week 16, PGMVC was −0.14% per month in the placebo and −0.27% per month in treated patients (P < 0.001). Over the same period, the decrease in PWMVC was −0.067% per month in the placebo and −0.116% per month in treated patients (P = 0.27). Similar changes were found in the group originally randomized to placebo when starting IFNβ‐1a treatment (week 16–40, reliability analysis). In the originally treated group, over 40 weeks, the decrease in PGMVC showed a significant (P < 0.001) quadratic component, indicating a plateauing at week 20.

Interpretation

Findings reported here add new insights into the complex mechanisms of pseudo‐atrophy and its relation to the compartmentalized inflammation occurring in the GM of MS patients. Ongoing and forthcoming clinical trials including MRI‐derived GM volume loss as an outcome measure need to account for potentially significant GM volume changes as part of the initial treatment effect.

Haematopoietic Stem Cell Transplantation for Multiple Sclerosis: Current Status

Autologous haematopoietic stem cell transplantation (AHSCT) is a treatment option for aggressive forms of multiple sclerosis (MS) that has been derived from haematological indications and repurposed for treatment of refractory autoimmune diseases. In the present review, a search for clinical studies on AHSCT was performed on the PubMed website and ClinicalTrials.gov databases. Papers were selected according to the following criteria: text written in English language, publication date between 2014 and August 2019, and reports including more than five patients. Prospective randomised and uncontrolled trials and retrospective case series were reviewed to examine the safety and efficacy of the procedure. Treatment protocols, pathological data and economic aspects of AHSCT were also succinctly covered. Growing evidence suggests that long-term suppression of inflammatory activity with stabilization or improvement of disability can be achieved in a high proportion of properly selected patients. More sophisticated outcome measures recently adopted, including effect on brain atrophy and disease biomarkers, are giving further insight into the effectiveness of transplant. The risks of the procedure have decreased to levels that can be considered acceptable for treatment of individuals with aggressive forms of MS. Careful selection of patients with an expected good benefit/risk profile, which is maximal when AHSCT is performed in early phases of the disease, and the expertise of transplant centres are critical to the success of treatment. Higher efficacy of AHSCT than with conventional treatments has recently been demonstrated by one randomised trial and further evidence is awaited from ongoing and planned trials comparing AHSCT with the most effective disease-modifying therapeutic agents.

Recent advances and remaining questions of autologous hematopoietic stem cell transplantation in multiple sclerosis

The judicious use of autologous hematopoietic stem cell transplantation (AHSCT) for MS requires understanding the potential benefits, identifying the most appropriate patient, and acknowledging the risks and differences between different protocols. Recently, AHSCT for MS is occurring more frequently, with a better safety profile than earlier studies. This review assesses recently published studies to determine the advances that have been made and remaining questions that future studies are poised to answer. We included studies from January 2016 to November 2020 with 20 or more patients. The benefits of AHSCT, including "no evidence of disease activity", functional and patient-reported outcomes, novel biomarkers such as brain atrophy or neurofilament light chain, and cost-effectiveness were assessed. The patient selection, treatment protocols, and safety outcomes differ between reports. The overall efficacy of AHSCT is better than standard treatments. Younger patients with highly active disease have greater chance for improvement, while patients who have comorbidities, failed more treatments, and are transitioning to a more progressive phase may not respond as well to AHSCT. The safety profiles for all AHSCT protocols is improving, however the durability of treatment response may not be the same for all protocols. The goal of AHSCT is to stop disease activity, avoid worsening disability, and obviate the need for further disease-modifying treatment, while improving patient quality of life and minimizing treatment-related risk. Results from currently enrolling randomized controlled trials, as well as ongoing registries, will provide more evidence for the safe and appropriate use of AHSCT.

Disability Improvement Is Associated with Less Brain Atrophy Development in Multiple Sclerosis

BACKGROUND AND PURPOSE

It is unknown whether deceleration of brain atrophy is associated with disability improvement in patients with MS. Our aim was to investigate whether patients with MS with disability improvement develop less brain atrophy compared with those who progress in disability or remain stable.

MATERIALS AND METHODS

We followed 980 patients with MS for a mean of 4.8 ± 2.4 years. Subjects were divided into 3 groups: progress in disability (n = 241, 24.6%), disability improvement (n = 101, 10.3%), and stable (n = 638, 65.1%) at follow-up. Disability improvement and progress in disability were defined on the basis of the Expanded Disability Status Scale score change using standardized guidelines. Stable was defined as nonoccurrence of progress in disability or disability improvement. Normalized whole-brain volume was calculated using SIENAX on 3D T1WI, whereas the lateral ventricle was measured using NeuroSTREAM on 2D-T2-FLAIR images. The percentage brain volume change and percentage lateral ventricle volume change were calculated using SIENA and NeuroSTREAM, respectively. Differences among groups were investigated using ANCOVA, adjusted for age at first MR imaging, race, T2 lesion volume, and corresponding baseline structural volume and the Expanded Disability Status Scale.

RESULTS

At first MR imaging, there were no differences among progress in disability, disability improvement, and the stable groups in whole-brain volume (P = .71) or lateral ventricle volume (P = .74). During follow-up, patients with disability improvement had the lowest annualized percentage lateral ventricle volume change (1.6% ± 2.7%) followed by patients who were stable (2.1% ± 3.7%) and had progress in disability (4.1% ± 5.5%), respectively (P < .001). The annualized percentage brain volume change values were -0.7% ± 0.7% for disability improvement, -0.8% ± 0.7% for stable, and -1.1% ± 1.1% for progress in disability (P = .001).

CONCLUSIONS

Patients with MS who improve in their clinical disability develop less brain atrophy across time compared with those who progress.

Approved and Emerging Disease Modifying Therapies on Neurodegeneration in Multiple Sclerosis

Multiple sclerosis (MS) is an autoimmune, chronic, progressive disease leading to a combination of inflammation, demyelination, and neurodegeneration throughout the central nervous system (CNS). The outcome of these processes can be visualized in magnetic resonance imaging (MRI) scans as brain atrophy, or brain volume loss (BVL), as well as lesions, “black holes” and spinal cord atrophy. MRI outcomes such as BVL have been used as biomarkers of neurodegeneration and other measures of MS disease progression in clinical research settings. Several FDA-approved medications seek to alleviate disease progression by reducing the impact of such factors as demyelination and neurodegeneration, but there are still many shortcomings that current clinical research aims to mitigate. This review attempts to provide an overview of the FDA-approved medications available for treating multiple sclerosis and their effect on neurodegeneration, measured by BVL.

Neurotoxicity after hematopoietic stem cell transplant in multiple sclerosis

OBJECTIVE

Accelerated brain volume loss has been noted following immunoablative autologous hematopoietic stem cell transplantation (IAHSCT) for multiple sclerosis. As with other MS treatments, this is often interpreted as 'pseudoatrophy', related to reduced inflammation. Treatment-related neurotoxicity may be contributory. We sought objective evidence of post-IAHSCT toxicity by quantifying levels of Neurofilament Light Chain (sNfL) and Glial Fibrillary Acidic Protein (sGFAP) before and after treatment as markers of neuroaxonal and glial cell damage.

METHODS

Sera were collected from 22 MS patients pre- and post-IAHSCT at 3, 6, 9, and 12 months along with 28 noninflammatory controls. sNfL and sGFAP quantification was performed using the SiMoA single-molecule assay.

RESULTS

Pre-IAHSCT levels of sNfL and sGFAP were elevated in MS patients compared with controls (geometric mean sNfL 21.8 vs. 6.4 pg/mL, sGFAP 107.4 vs. 50.7 pg/mL, P = 0.0001 for both). Three months after IAHSCT, levels of sNfL and sGFAP increased from baseline by 32.1% and 74.8%, respectively (P = 0.0029 and 0.0004). sNfL increases correlated with total busulfan dose (P = 0.034), EDSS score worsening at 6 months (P = 0.041), and MRI grey matter volume loss at 6 months (P = 0.0023). Subsequent NfL levels reduced to less than baseline (12-month geometric mean 11.3 pg/mL P = 0.0001) but were still higher than controls (P = 0.0001). sGFAP levels reduced more slowly but at 12 months were approaching baseline levels (130.7 pg/mL).

INTERPRETATION

There is direct evidence of transient CNS toxicity immediately after IAHSCT which may be chemotherapy mediated and contributes to transient increases in MRI atrophy.

Impact of autologous haematopoietic stem cell transplantation on disability and brain atrophy in secondary progressive multiple sclerosis

Background:

Autologous haematopoietic stem cell transplantation (aHSCT) is a valuable option in aggressive relapsing–remitting multiple sclerosis (MS), but its efficacy in secondary progressive (SP)-MS is still controversial.

Objective:

Assessing efficacy of aHSCT in SP-MS by clinical-radiological outcomes.

Methods:

Open-label monocentric retrospective study enrolling consecutive SP-MS patients treated with BEAM-aHSCT in the period 1999–2016.

Results:

In total, 26 SP-MS patients with moderate–severe disability were included. Progression-free survival (PFS) at years 5 and 10 after aHSCT were, respectively, 42% and 30%. Out of 16 patients who worsened, only 6 patients (23% overall) maintained continuous disability accrual (CDA), whereas 10 patients stabilized following one single-step Expanded Disability Status Scale (EDSS) worsening. CDA-free survival was 74% at 5–10 years. No relapses or magnetic resonance imaging (MRI) activity were reported, thus no evidence of disease activity (NEDA)-3 corresponded to PFS. Annualized rate of brain atrophy (AR-BVL) normalized after 1 year in 55% of the cases analysed (12/22).

Conclusion:

BEAM-aHSCT halted CDA and normalized AR-BVL in most of the treated patients, inducing long-term remission of inflammatory activity at a median follow-up of 99 months (range 27–222). These data suggest that CDA might still be mainly driven by inflammation in a subgroup of SP-MS and could therefore be reversed by treatments. CDA should be analysed independently from any isolated disability worsening.

Sustained remission in multiple sclerosis after hematopoietic stem cell transplantation

OBJECTIVES

To determine whether treatment with autologous hematopoietic stem cell transplantation (HSCT) can induce sustained complete remission in patients with multiple sclerosis (MS).

MATERIAL AND METHODS

Case series of patients with relapsing-remitting MS (n = 10) treated at a single center between 2004 and 2007 and followed up for 10 years. The patients were treated with a BEAM/ATG conditioning regimen (n = 9) or a cyclophosphamide/ATG conditioning regimen (n = 1) followed by infusion of unmanipulated autologous hematopoietic stem cells. The primary endpoint was sustained complete remission. Sustained complete remission was defined as "no evidence of disease activity-4," sustained for a period of at least 5 years without any ongoing disease-modifying treatment. Furthermore, MS was considered as "resolved" if intrathecal IgG production and cerebrospinal fluid neurofilament light levels were normalized as well.

RESULTS

Five out of 10 patients were in sustained complete remission at the end of the study. In three of them, MS was resolved.

CONCLUSIONS

Our data demonstrate that sustained complete remission after autologous HSCT for MS is possible.

Immune reconstitution therapy (IRT) in multiple sclerosis: the rationale

Immunotherapy of multiple sclerosis (MS) and other neuroimmune diseases is rapidly evolving. For the past 25 years, there has been an accelerating inclusion of new immunomodulating drugs. Based on their molecular construction and their basic mechanism of action, immunotherapeutic agents belong to the following categories: (1) cytotoxic drugs, (2) synthetic immunomodulators, (3) monoclonal antibodies, (4) vaccines (T cell vaccines, antigen vaccines), (5) oral tolerizing agents, (6) modalities that act as indirect immunosuppressants (plasmapheresis, intravenous immunoglobulins [IVIG]), and (7) cellular therapies. MS immunotherapies may also be classified in a different way, into treatments that are given continuously (chronic treatments) and medications that are applied intermittently (IRTs). The principle behind the latter is depletion of the immune system that allows it to rebuild itself. Upon its reconstitution/resetting, the immune system regains the ability to respond to infections and survey the periphery for cancer. An IRT by definition is given at short intermittent courses and not continuously. IRT modalities were shown to induce long-term remission of MS that, in some cases, is close to the definition of a "cure." There are cohorts of patients having been treated with the IRTs, alemtuzumab, and HSCT, who experience-under these modalities-no evidence of disease activity (NEDA) for over 10 years. Most importantly, IRTs cause radical changes in the lymphocyte repertoire after the reconstitution phase that may explain the long-term beneficial effects of IRT and the possibility of re-induction of self-tolerance to self/myelin antigens. In comparison, a chronic treatment cannot result in cure of the autoimmune reactivity, because it only blocks the immune system, as long as it is given; it cannot therefore radically affect the immunopathogenesis of the disease. The risks of adverse events related to immune suppression (such as opportunistic infections and secondary malignancies) with IRTs are lower and front-loaded, whereas the common side effects of chronic immunomodulation are higher and accumulate with time. In conclusion, IRT provides a novel concept for MS therapy with substantial advantages over chronic immunosuppression. IRT therapies have shown a significantly higher level of efficacy in MS. The "Holy grail" of the treatment of autoimmunity, which is to re-induce the disrupted self-tolerance, seems to be achievable-at least in part-with this approach. Moreover, the benefits of IRT, administered in short pulses, include significantly higher adherence to treatment and lower risks for accumulative side effects that are typically associated with chronic immunosuppression.

Application of advanced MRI techniques to monitor pharmacologic and rehabilitative treatment in multiple sclerosis: current status and future perspectives

Introduction: Advances in magnetic resonance imaging (MRI) technology and analyses are improving our understanding of the pathophysiology of multiple sclerosis (MS). Due to their ability to grade the presence of irreversible tissue loss, microstructural tissue abnormalities, metabolic changes and functional plasticity, the application of these techniques is also expanding our knowledge on the efficacy and mechanisms of action of different pharmacological and rehabilitative treatments. Areas covered: This review discusses recent findings derived from the application of advanced MRI techniques to evaluate the structural and functional substrates underlying the effects of pharmacologic and rehabilitative treatments in patients with MS. Current applications as outcome in clinical trials and observational studies, their interpretation and possible pitfalls in their use are discussed. Finally, how these techniques could evolve in the future to improve monitoring of disease progression and treatment response is examined. Expert commentary: The number of treatments currently available for MS is increasing. The application of advanced MRI techniques is providing reliable and specific measures to better understand the targets of different treatments, including neuroprotection, tissue repair, and brain plasticity. This is a fundamental progress to move toward personalized medicine and individual treatment selection.

Cladribine tablets' potential role as a key example of selective immune reconstitution therapy in multiple sclerosis

Multiple sclerosis (MS) is one of the most important, disabling, and prevalent neurological disorders of young adults. It is a chronic inflammatory and neurodegenerative disease when autoreactive B and T cells have downstream effects that result in demyelination and neuronal loss. Anti-inflammatory disease-modifying therapies do have proven efficacy in delaying disease and disability progression in MS. While the progress in MS treatments has already improved the prognosis and quality of patients’ lives overall, there are some clear shortcomings and unmet needs in the current MS treatment landscape. The most promising means of MS treatment is selective immune reconstitution therapy (SIRT). This therapy is given in short-duration courses of immunosuppression, producing durable effects on the immune system and preventing nervous tissue loss. This review discusses the mechanisms of action and the data of clinical trials of cladribine tablets as an example of SIRT in MS. The clinical benefits of cladribine tablets in these studies include decreased relapse rate and disability progression with large reductions in lesion activity, and protection against brain volume loss. Whether all of these neurological findings are direct results of lymphocyte depletion, or if there are downstream effects on other, unknown, neurodegenerative processes are yet to be determined, but these clearly point to an interesting area of research.

Autologous haematopoietic stem cell transplantation for neurological diseases

Neuroinflammatory diseases such as multiple sclerosis, neuromyelitis optica, chronic inflammatory demyelinating polyneuropathy and myasthenia gravis are leading causes of physical disability in people of working age. In the last decades significant therapeutic advances have been made that can ameliorate the disease course. Nevertheless, many affected will continue to deteriorate despite treatment, and the costs associated with disease-modifying drugs constitute a significant fiscal burden on healthcare in developed countries. Autologous haematopoietic stem cell transplantation is a treatment approach that aims to ameliorate and to terminate disease activity. The erroneous immune system is eradicated using cytotoxic drugs, and with the aid of haematopoietic stem cells a new immune system is rebuilt. As of today, more than 1000 patients with multiple sclerosis have been treated with this procedure. Available data suggest that autologous haematopoietic stem cell transplantation is superior to conventional treatment in terms of efficacy with an acceptable safety profile. A smaller number of patients with other neuroinflammatory conditions have been treated with promising results. Herein, current data on clinical effect and safety of autologous haematopoietic stem cell transplantation for neurological disease are reviewed.

Chronic low-level expression of HIV-1 Tat promotes a neurodegenerative phenotype with aging

The widespread use of combinational antiretroviral therapies (cART) in developed countries has changed the course of Human Immunodeficiency Virus (HIV) infection from an almost universally fatal disease to a chronic infection for the majority of individuals. Although cART has reduced the severity of neurological damage in HIV-infected individuals, the likelihood of cognitive impairment increases with age, and duration of infection. As cART does not suppress the expression of HIV non-structural proteins, it has been proposed that a constitutive production of HIV regulatory proteins in infected brain cells may contribute to neurological damage. However, this assumption has never been experimentally tested. Here we take advantage of the leaky tetracycline promoter system in the Tat-transgenic mouse to show that a chronic very low-level expression of Tat is associated with astrocyte activation, inflammatory cytokine expression, ceramide accumulation, reductions in brain volume, synaptic, and axonal damage that occurs over a time frame of 1 year. These data suggest that a chronic low-level production of Tat may contribute to progressive neurological damage in virally suppressed HIV-infected individuals.

Modulating inflammation and neuroprotection in multiple sclerosis

Multiple sclerosis (MS) is a neurological disorder of the central nervous system with a presentation and disease course that is largely unpredictable. MS can cause loss of balance, impaired vision or speech, weakness and paralysis, fatigue, depression, and cognitive impairment. Immunomodulation is a major target given the appearance of focal demyelinating lesions in myelin-rich white matter, yet progression and an increasing appreciation for gray matter involvement, even during the earliest phases of the disease, highlights the need to afford neuroprotection and limit neurodegenerative processes that correlate with disability. This review summarizes key aspects of MS pathophysiology and histopathology with a focus on neuroimmune interactions in MS, which may facilitate neurodegeneration through both direct and indirect mechanisms. There is a focus on processes thought to influence disease progression and the role of oxidative stress and mitochondrial dysfunction in MS. The goals and efficacy of current disease-modifying therapies and those in the pipeline are discussed, highlighting recent advances in our understanding of pathways mediating disease progression to identify and translate both immunomodulatory and neuroprotective therapeutics from the bench to the clinic.

High-dose immunosuppressive therapy and autologous HCT for relapsing-remitting MS

OBJECTIVE

To evaluate the safety, efficacy, and durability of multiple sclerosis (MS) disease stabilization after high-dose immunosuppressive therapy (HDIT) and autologous hematopoietic cell transplantation (HCT).

METHODS

High-Dose Immunosuppression and Autologous Transplantation for Multiple Sclerosis (HALT-MS) is a phase II clinical trial of HDIT/HCT for patients with relapsing-remitting (RR) MS who experienced relapses with disability progression (Expanded Disability Status Scale [EDSS] 3.0-5.5) while on MS disease-modifying therapy. The primary endpoint was event-free survival (EFS), defined as survival without death or disease activity from any one of: disability progression, relapse, or new lesions on MRI. Participants were evaluated through 5 years posttransplant. Toxicities were reported using the National Cancer Institute Common Terminology Criteria for Adverse Events (AE).

RESULTS

Twenty-five participants were evaluated for transplant and 24 participants underwent HDIT/HCT. Median follow-up was 62 months (range 12-72). EFS was 69.2% (90% confidence interval [CI] 50.2-82.1). Progression-free survival, clinical relapse-free survival, and MRI activity-free survival were 91.3% (90% CI 74.7%-97.2%), 86.9% (90% CI 69.5%-94.7%), and 86.3% (90% CI 68.1%-94.5%), respectively. AE due to HDIT/HCT were consistent with expected toxicities and there were no significant late neurologic adverse effects noted. Improvements were noted in neurologic disability with a median change in EDSS of -0.5 (interquartile range -1.5 to 0.0; p = 0.001) among participants who survived and completed the study.

CONCLUSION

HDIT/HCT without maintenance therapy was effective for inducing long-term sustained remissions of active RRMS at 5 years.

CLINICALTRIALSGOV IDENTIFIER

NCT00288626.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that participants with RRMS experienced sustained remissions with toxicities as expected from HDIT/HCT.

Brain atrophy after bone marrow transplantation for treatment of multiple sclerosis

Background:

A cohort of patients with poor-prognosis multiple sclerosis (MS) underwent chemotherapy-based immune ablation followed by immune reconstitution with an autologous hematopoietic stem cell transplant (IA/aHSCT). This eliminated new focal inflammatory activity, but resulted in early acceleration of brain atrophy.

Objective:

We modeled the time course of whole-brain volume in 19 patients to identify the baseline predictors of atrophy and to estimate the average rate of atrophy after IA/aHSCT.

Methods:

Percentage whole-brain volume changes were calculated between the baseline and follow-up magnetic resonance imaging (MRI; mean duration: 5 years). A mixed-effects model was applied using two predictors: total busulfan dose and baseline volume of T1-weighted white-matter lesions.

Results:

Treatment was followed by accelerated whole-brain volume loss averaging 3.3%. Both the busulfan dose and the baseline lesion volume were significant predictors. The atrophy slowed progressively over approximately 2.5 years. There was no evidence that resolution of edema contributed to volume loss. The mean rate of long-term atrophy was −0.23% per year, consistent with the rate expected from normal aging.

Conclusion:

Following IA/aHSCT, MS patients showed accelerated whole-brain atrophy that was likely associated with treatment-related toxicity and degeneration of “committed” tissues. Atrophy eventually slowed to that expected from normal aging, suggesting that stopping inflammatory activity in MS can reduce secondary degeneration and atrophy.

Clinical relevance of brain atrophy assessment in multiple sclerosis. Implications for its use in a clinical routine

INTRODUCTION

Brain atrophy measurement in multiple sclerosis (MS) has become an important outcome for determining patients at risk for developing physical and cognitive disability.

AREAS COVERED

In this article, we discuss the methodological issues related to using this MRI metric routinely, in a clinical setting. Understanding trajectories of annualized whole brain, gray and white matter, thalamic volume loss, and enlargement of ventricular space in specific MS phenotypes is becoming increasingly important. Evidence is mounting that disease-modifying treatments exert a positive effect on slowing brain atrophy progression in MS. Expert Commentary: While there is a need to translate measurement of brain atrophy to clinical routine at the individual patient level, there are still a number of challenges to be met before this can actually happen, including how to account for biological confounding factors and pseudoatrophy, standardize acquisition and analyses parameters, which can influence the accuracy of the assessments.

Aggressive multiple sclerosis: proposed definition and treatment algorithm

Multiple sclerosis (MS) is a CNS disorder characterized by inflammation, demyelination and neurodegeneration, and is the most common cause of acquired nontraumatic neurological disability in young adults. The course of the disease varies between individuals: some patients accumulate minimal disability over their lives, whereas others experience a rapidly disabling disease course. This latter subset of patients, whose MS is marked by the rampant progression of disability over a short time period, is often referred to as having 'aggressive' MS. Treatment of patients with aggressive MS is challenging, and optimal strategies have yet to be defined. It is important to identify patients who are at risk of aggressive MS as early as possible and implement an effective treatment strategy. Early intervention might protect patients from irreversible damage and disability, and prevent the development of a secondary progressive course, which thus far lacks effective therapy.

High-dose immunosuppressive therapy and autologous hematopoietic cell transplantation for relapsing-remitting multiple sclerosis (HALT-MS): a 3-year interim report

IMPORTANCE

Most patients with relapsing-remitting (RR) multiple sclerosis (MS) who receive approved disease-modifying therapies experience breakthrough disease and accumulate neurologic disability. High-dose immunosuppressive therapy (HDIT) with autologous hematopoietic cell transplant (HCT) may, in contrast, induce sustained remissions in early MS.

OBJECTIVE

To evaluate the safety, efficacy, and durability of MS disease stabilization through 3 years after HDIT/HCT.

DESIGN, SETTING, AND PARTICIPANTS

Hematopoietic Cell Transplantation for Relapsing-Remitting Multiple Sclerosis (HALT-MS) is an ongoing, multicenter, single-arm, phase 2 clinical trial of HDIT/HCT for patients with RRMS who experienced relapses with loss of neurologic function while receiving disease-modifying therapies during the 18 months before enrolling. Participants are evaluated through 5 years after HCT. This report is a prespecified, 3-year interim analysis of the trial. Thirty-six patients with RRMS from referral centers were screened; 25 were enrolled.

INTERVENTIONS

Autologous peripheral blood stem cell grafts were CD34+ selected; the participants then received high-dose treatment with carmustine, etoposide, cytarabine, and melphalan as well as rabbit antithymocyte globulin before autologous HCT.

MAIN OUTCOMES AND MEASURES

The primary end point of HALT-MS is event-free survival defined as survival without death or disease activity from any one of the following outcomes: (1) confirmed loss of neurologic function, (2) clinical relapse, or (3) new lesions observed on magnetic resonance imaging. Toxic effects are reported using National Cancer Institute Common Terminology Criteria for Adverse Events.

RESULTS

Grafts were collected from 25 patients, and 24 of these individuals received HDIT/HCT. The median follow-up period was 186 weeks (interquartile range, 176-250) weeks). Overall event-free survival was 78.4% (90% CI, 60.1%-89.0%) at 3 years. Progression-free survival and clinical relapse-free survival were 90.9% (90% CI, 73.7%-97.1%) and 86.3% (90% CI, 68.1%-94.5%), respectively, at 3 years. Adverse events were consistent with expected toxic effects associated with HDIT/HCT, and no acute treatment-related neurologic adverse events were observed. Improvements were noted in neurologic disability, quality-of-life, and functional scores.

CONCLUSIONS AND RELEVANCE

At 3 years, HDIT/HCT without maintenance therapy was effective for inducing sustained remission of active RRMS and was associated with improvements in neurologic function. Treatment was associated with few serious early complications or unexpected adverse events.

Magnetic resonance outcome measures in multiple sclerosis trials: time to rethink?

PURPOSE OF REVIEW

We summarize MRI measures currently available to assess treatment efficacy and safety in multiple sclerosis (MS) clinical trials and discuss novel metrics that could enter the clinical arena in the near future.

RECENT FINDINGS

In relapsing remitting MS, MRI measures of disease activity (new T2 and gadolinium-enhancing lesions) provide a good surrogacy of treatment effect on relapse rate and disability progression; however, their value in progressive MS remains elusive. For the progressive disease forms, these measures need to be combined with quantities assessing the extent of irreversible tissue loss, which have already been introduced in some clinical trials (e.g., evolution of active lesions into permanent black holes and brain atrophy). Novel measures (e.g., quantification of gray matter and spinal cord atrophy) have demonstrated a great value in explaining patients' clinical outcome, but still need to be fully validated. Despite showing promise, evaluations of cortical lesions, of microscopic tissue abnormalities, and of functional cortical reorganization are still some way off for monitoring of treatment effects.

SUMMARY

Trial outcomes in MS should include measures of inflammation and neurodegeneration, which should be combined according to the disease clinical phenotype, phase of the study, and the supposed mechanism of action of the drug tested.

Future treatment approaches to multiple sclerosis

The modern treatment era for multiple sclerosis (MS) began in 1993 with the approval of the first disease-modifying agent. Since then the field has greatly expanded, with 10 therapies currently approved to treat MS. These treatments are effective to reduce relapses and changes on MRI, and slow disability. However, despite these medications some patients continue to have exacerbations, accumulate disability, and develop progressive disease due to partial effectiveness. New molecules with novel mechanisms of action and targets are being explored. Hopefully these agents will yield even greater efficacy without significant safety concerns. As more aggressive therapies are available to treat MS, the goals and expectations of treatment are also likely to change. Some of the emerging therapies, including alemtuzumab, daclizumab, rituximab, ocrelizumab, laquinimod, estriol, 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins), vitamin D, and stem cell transplantation, will be discussed in this chapter. In the future, therapies with different mechanisms may be combined, but this will need to be evaluated in clinical trials. Neuroprotection and repair definitely warrant further study. The future of MS treatment is very exciting, especially as our armamentarium expands.

Correlation between brain volume change and T2 relaxation time induced by dehydration and rehydration: implications for monitoring atrophy in clinical studies

Brain volume change measured from magnetic resonance imaging (MRI) provides a widely used and useful in vivo measure of irreversible tissue loss. These measurements, however, can be influenced by reversible factors such as shifts in brain water content. Given the strong effect of water on T2 relaxation, we investigated whether an estimate of T2 relaxation time would correlate with brain volume changes induced by physiologically manipulating hydration status. We used a clinically feasible estimate of T2 ("pseudo-T2") computed from a dual turbo spin-echo MRI sequence and correlated pseudo-T2 changes to percent brain volume changes in 12 healthy subjects after dehydration overnight (16-hour thirsting) and rehydration (drinking 1.5 L of water). We found that the brain volume significantly increased between the dehydrated and rehydrated states (mean brain volume change = 0.36%, p = 0.0001) but did not change significantly during the dehydration interval (mean brain volume change = 0.04%, p = 0.57). The changes in brain volume and pseudo-T2 significantly correlated with each other, with marginal and conditional correlations (R (2)) of 0.44 and 0.65, respectively. Our results show that pseudo-T2 may be used in conjunction with the measures of brain volume to distinguish reversible water fluctuations and irreversible brain tissue loss (atrophy) and to investigate disease mechanisms related to neuro-inflammation, e.g., in multiple sclerosis, where edema-related water fluctuations may occur with disease activity and anti-inflammatory treatment.

Advances in multiple sclerosis and its variants: conventional and newer imaging techniques

Multiple sclerosis (MS) and its variants are inflammatory as well as neurodegenerative diseases that diffusely affect the central nervous system (CNS). There is a poor correlation between traditional imaging findings and symptoms in patients with MS. Current research in conventional magnetic resonance (MR) imaging of MS and related diseases includes optimization of hardware and pulse sequences and the development of automated and semiautomated techniques to measure and quantify disease burden. Advanced nonconventional MR techniques such as diffusion tensor and functional MR imaging probe the changes found in the CNS, and correlate these findings with clinical measures of disease.

Hematopoietic stem cell transplantation in multiple sclerosis

It is widely accepted that the main common pathogenetic pathway in multiple sclerosis (MS) involves an immune-mediated cascade initiated in the peripheral immune system and targeting CNS myelin. Logically, therefore, therapeutic approaches to the disease include modalities aiming at downregulation of the various immune elements that are involved in this immunological cascade. Since the introduction of interferons in 1993, more specific immunoactive drugs have been introduced, but still most of them can, at best, effectively modulate only the early relapsing phases of MS. The more progressed phases of the disease are not efficiently amendable by the existing immunomodulatory drugs. Moreover, localized and compartmentized inflammation in the CNS, which seems to be mostly responsible for the chronic axonal damage and resulting progression of disability, is less affected by the current drugs. A more radical approach to suppress all the inflammation in MS, including that into the CNS, could theoretically be achieved with high-dose immunosuppression using strong cytotoxic medications and resetting of the immune system by hematopoietic stem cell transplantation (HSCT). HSCT, both allogeneic and autologous, has been tried as a novel therapeutic approach in various autoimmune diseases. During the last 15 years several (mostly open) clinical studies evaluated the effect of HSTC on MS patients; the published papers showed that a high proportion of the HSCT-treated MS patients were stabilized, or even improved after the transplantation and have generally indicated a beneficial effect on disease progression. In this review, the rationale of HSCT and the summary of the results of the existing clinical trials are presented. Despite the fact that it is difficult to collectively summarize the results of all the trials, due to lack of uniformity in the conditioning and treatment protocols and of completed controlled studies, these clinical studies have provided a strong 'proof of concept' for HSCT in MS and have significantly contributed to our understanding of the advantages and disadvantages of each approach and HSCT protocol.

Cognitive fatigue in individuals with multiple sclerosis undergoing immunoablative therapy and hematopoietic stem cell transplantation

BACKGROUND

Fatigue presents as a significant problem in multiple sclerosis (MS). Cognitive fatigue (CF) can be defined as a decrease in, or inability to maintain task performance throughout the duration of a continuous cognitive task. CF was evaluated using the Paced Auditory Serial Addition Test (PASAT) both pre- and post-immunoablation and hematopoietic stem cell transplantation (IA-HSCT) over a 3-year follow-up period. The magnitude of CF was examined and the impact of scoring methodology was evaluated.

METHODS

Twenty-three individuals with rapidly progressive MS and poor prognosis underwent high dose immunosuppression and subsequent HSCT. Individuals completed the 3″ and 2″ PASAT at baseline and every 6 months thereafter over a period of 36 months. As scoring methodology can impact its sensitivity to CF, the PASAT was scored according to three scoring methods.

RESULTS

CF was noted across all three scoring methods at baseline and at the majority of time points post-IA-HSCT on both the 3″ and 2″ PASAT. The magnitude of CF remained consistent both pre-and post-IA-HSCT.

CONCLUSIONS

While results suggest that the procedure itself does not ameliorate an individual's susceptibility to CF; neither does it seem to negatively impact levels of CF. As such, results support the notion that the IA-HSCT procedure, despite its aggressive nature, does not exacerbate CF in this particular sample.

Cognitive change and neuroimaging following immunoablative therapy and hematopoietic stem cell transplantation in multiple sclerosis: A pilot study

BACKGROUND

Individuals with MS undergoing immunoablative therapy and hematopoietic stem cell transplantation (HSCT) show substantial decrease in brain volume over 2.4 months, presumably from chemotoxic effects, although other mechanisms have also been postulated.

OBJECTIVE

We examined whether volume loss was accompanied by a concomitant decrease in cognition. White and gray matter volumes, and the effect of stem cell dosage were considered.

METHODS

Seven individuals with rapidly progressing MS and poor prognosis underwent high dose immunosuppression and autologous HSCT. Neuropsychological testing and MRI scans were performed at baseline, 2 and 24 months post-procedure.

RESULTS

Cognitive impairment was noted at all times in most participants. Median decline of 1.39% in total brain volume was noted 2 months post-HSCT. By 24 months a further decline of 1.65% was noted. At 2 months significant decline was observed for areas of executive functioning. At 24 months almost no significant declines were noted. No significant correlations were found between cognitive decline and change in imaging variables or stem cell dosage.

CONCLUSIONS

Cognition changed in the early period following treatment but with little apparent relationship to volume changes. With temporal distance from the HSCT procedure, cognition returned to baseline levels. With the caution of a very small sample, preliminary results suggest that immunoablation and HSCT may have no lasting deleterious effects on cognition.

Hematopoietic stem cell therapy for multiple sclerosis: top 10 lessons learned

Reports from more than 600 hematopoietic stem cell transplants (HSCT) have appeared in the medical literature for the last 1 and one-half decades. The patient's own stem cells are harvested and stored temporarily while high doses of chemotherapy and biologics are used to destroy the auto-destructive immune system. The immune system is regenerated from the infused autologous hematopoietic stem cells. Increasing clinical experience has refined patient selection criteria and management in the peri-transplant period leading to a reduction in treatment-related complications. HSCT, when used to treat patients with aggressive highly active multiple sclerosis, can reduce or eliminate ongoing clinical relapses, halt further progression, and reduce the burden of disability in some patients, in the absence of chronic treatment with disease-modifying agents. The top 10 lessons learned from the growing experience using HSCT for the treatment of multiple sclerosis are discussed.

Autologous hematopoietic cell transplantation following high-dose immunosuppressive therapy for advanced multiple sclerosis: long-term results

The purpose of the study was to determine the long-term safety and effectiveness of high-dose immunosuppressive therapy (HDIT) followed by autologous hematopoietic cell transplantation (AHCT) in advanced multiple sclerosis (MS). Total body irradiation, cyclophosphamide, and antithymocyte globulin were followed by transplantation of autologous, CD34-selected peripheral blood stem cells (PBSC). Neurological examinations, brain MRIs and cerebrospinal fluid (CSF) for oligoclonal bands (OCB) were serially evaluated. Patients (n=26, mean EDSS=7.0, 17 secondary progressive, 8 primary progressive, 1 relapsing/remitting) were followed for a median of 48 months after HDIT followed by AHCT. The 72-month probability of worsening ≥ 1.0 EDSS point was 0.52 (95% CI, 0.30 to 0.75). Five patients had an EDSS at baseline of ≤ 6.0; four of these had not failed treatment at last study visit. OCB in CSF persisted with minor changes in the banding pattern. Four new or enhancing lesions were seen on MRI, all within 13 months of treatment. In this population with high baseline EDSS, a significant proportion of patients with advanced MS remained stable as long as 7 years after transplant. Non-inflammatory events may have contributed to neurological worsening after treatment. HDIT/AHCT may be more effective in patients with less advanced relapsing/remitting MS.

Escalating immunotherapy of multiple sclerosis

Basic disease-modifying treatment for relapsing forms of active multiple sclerosis (MS) is now available in many countries with high prevalence rates, for this chronic inflammatory disease of the central nervous system. Several lines of evidence support early immunomodulatory treatment with either recombinant interferon-beta or glatiramer acetate, and positive results from phase III trials encourage start of treatment even in patients with clinically isolated syndromes (CIS). However, currently available drugs for basic therapy are only partially effective and patients may still encounter relapses or disease progression. As treatment-refractory, clinically active MS can quickly lead to irreversible neurological disability there is an urgent need for effective escalating strategies. Patients with suboptimal treatment response to basic therapy have been treated with combination therapies, cytotoxic drugs (such as mitoxantrone and cyclophosphamide) or autologous hematopoietic stem cell transplantation. Recently, the monoclonal antibody, natalizumab, was added to this armamentarium. None of these strategies have been vigorously evaluated in large randomized, controlled phase III trials with patients who failed basic therapy. Therefore, the decision to escalate immunotherapy is still based on limited evidence. This article will review potential candidates for intensified immunosuppression and call for innovative study designs to better evaluate escalating immunotherapy in MS.

Cyclophosphamide in multiple sclerosis: scientific rationale, history and novel treatment paradigms

For patients with relapsing-remitting multiple sclerosis (RRMS), there are currently six approved medications that have been shown to alter the natural course of the disease. The approved medications include three beta interferon formulations, glatiramer acetate, natalizumab and mitoxantrone. Treating aggressive forms of RRMS and progressive disease forms of MS still presents a great challenge to neurologists. Intense immunosuppression has long been thought to be the only feasible therapeutic option. In patients with progressive forms of MS, lymphoid tissues have been detected in the central nervous system (CNS) that may play a critical role in perpetuating local inflammation. Agents that are currently approved for patients with MS have no or very limited bioavailability in the brain and spinal cord. In contrast, cyclophosphamide (CYC), an alkylating agent, penetrates the blood-brain barrier and CNS parenchyma well. However, while CYC has been used in clinical trials and off-label in clinical practice in patients with MS for over three decades, data on its efficacy in very heterogeneous groups of study patients have been conflicting. New myeloablative treatment paradigms with CYC may provide a therapeutic option in patients that do not respond to other agents. In this article we review the scientific rationale that led to the initial clinical trials with CYC. We will also outline the safety, tolerability and efficacy of CYC and provide neurologists with guidelines for its use in patients with MS and other inflammatory disorders of the CNS, including neuromyelitis optica (NMO). Finally, an outlook into relatively novel treatment approaches is provided.

Autologous hematopoietic stem cell transplantation in autoimmune diseases

The term 'autoimmune diseases' encompasses a spectrum of diseases whose clinical manifestations and, possibly, biological features vary widely. The results of conventional treatment are considered unsatisfactory in aggressive forms, with subsets of patients having short life expectancies. Relying on wide experimental evidence and more feeble clinical data, some research groups have used autologous hematopoietic stem cell transplantation (HSCT) in the most disabling autoimmune diseases with the aim of resetting the patient's immune system. Immunoablative conditioning regimens are preferred over their myeloablative counterparts, and some form of in vivo and/or ex vivo T-cell depletion is generally adopted. Despite 15 years' experience, published controlled clinical trials are still lacking, with the evidence so far available coming from pilot studies and registry surveys. In multiple sclerosis, clinical improvement, or at least lasting disease stabilization, can be achieved in the majority of the patients; nevertheless, the worst results are observed in patients with progressive disease, where no benefit can be expected from conventional therapy. Concerning rheumatologic diseases, wide experience has been acquired in systemic sclerosis, with long-term improvements in cutaneous disease being frequently reported, although visceral involvement remains unchanged at best. Autografting has proved to be barely effective in rheumatoid arthritis and quite toxic in juvenile idiopathic arthritis, whereas it leads to clinical remission and the reversal of visceral impairment in the majority of patients with systemic lupus erythematosus. A promising indication is Crohn's disease, in which long-term endoscopic remission is frequently observed. Growing experience with autologous HCST in autoimmune diseases has progressively reduced concerns about transplant-related mortality and secondary myelodysplasia/leukemia. Therefore, a sustained complete remission seems to be within the reach of autografting in some autoimmune diseases; in others, the indications, risks and benefits of autografting need to be better defined. Consequently, the search for new drugs should also be encouraged.

Evidence for acute neurotoxicity after chemotherapy

OBJECTIVE

Chronic neurotoxicity is a recognized long-term complication following chemotherapy in a range of diseases. Neurotoxicity adversely affects patients' quality of life. The objective of this study is to examine whether there is evidence of acute neurotoxicity.

METHODS

This prospective study included patients with secondary progressive multiple sclerosis (SPMS-BMT, n = 14) and hematological malignancies (HM-BMT, n = 17) receiving chemotherapy as preconditioning for bone marrow transplant. The control groups included SPMS patients matched for demographic and clinical data (SPMS-PL, n = 14) and healthy controls (n = 14). Neurodegeneration was assessed at baseline and longitudinally (months 1, 2, 3, 6, 9, 12, 24, and 36), combining a clinical scale for disability (Expanded Disability Status Scale [EDSS]), a serum protein biomarker for neurodegeneration (neurofilaments, NfH-SMI35), and brain atrophy measures (magnetic resonance imaging).

RESULTS

Disability progression was significantly more acute and severe following chemotherapy compared to placebo. Immediately after starting chemotherapy, serum NfH-SMI35 levels increased in 79% (p < 0.0001) of SPMS-BMT patients and 41% (p < 0.01) of HM-BMT patients compared to 0% of SPMS-PL patients or healthy controls. In SPMS-BMT serum NfH-SMI35 levels were > 100-fold higher 1 month after chemotherapy (29.73ng/ml) compared to baseline (0.28ng/ml, p < 0.0001). High serum NfH-SMI35 levels persisting for at least 3 months were associated with sustained disability progression on the EDSS (p < 0.05). Brain atrophy rates increased acutely in SPMS-BMT (-2.09) compared to SPMS-PL (-1.18, p < 0.05).

INTERPRETATION

Neurotoxicity is an unwanted acute side effect of aggressive chemotherapy.

Hematopoietic stem cell transplantation for multiple sclerosis: collaboration of the CIBMTR and EBMT to facilitate international clinical studies

Clinical investigation of autologous hematopoietic stem cell transplantation (HSCT) as therapy for multiple sclerosis (MS) has been ongoing for over a decade. While several phase II studies have been finalized or are in progress, no definitive prospective randomized studies comparing HSCT versus alternative therapies for MS have been completed. In this conference report of North American and European experts who are involved in the care of MS patients, including neurologists and HSCT physicians, and representatives of the Center for International Blood and Marrow Transplant Research (CIBMTR) and European Group for Blood and Marrow Transplantation (EBMT), we (1) critically review progress to date in HSCT for MS; (2) describe current registry based projects including long-term follow-up studies in HSCT for MS and harmonization of the MS disease-specific research forms that will be used in future by both databases; (3) discuss challenges in study design for a prospective randomized clinical trial of HSCT versus alternative therapy for MS such as feasibility, and the importance of multidisciplinary clinical teams, need for a large sample size and duration of observation required for outcomes assessment; and (4) address future directions in HSCT therapy for MS. To undertake a definitive multicenter clinical trial in autologous HSCT for MS, it will be important to begin well in advance to assemble the team, evaluate proposals for study design, and consider options for the infrastructure and logistical support that will be needed. International collaboration, including partnership with the CIBMTR and EBMT, may be desirable and may in fact be critical for successful completion of a definitive comparative study.

Hematopoietic stem cell transplantation in multiple sclerosis

Intensive immunosuppresion followed by hematopoietic stem cell transplantation (HSCT) has been suggested as potential treatment in severe forms of multiple sclerosis (MS). Since 1995 ca. 400 patients have been treated with HSCT. Stabilization or improvement occurred in almost 70% of cases at least for 3 years post-transplant. Magnetic resonance revealed the capacity of autologous HSCT to suppress or markedly reduce gadolinium-enhancing lesions. The progression of brain atrophy declined after two years post-HSCT. The profound immunological changes following autologous HSCT may result in restoration of self-tolerance. Relatively young patients with active inflammatory lesions of relatively short duration and rapidly progressive disease, but still low disability scores, unresponsive to conventional therapy seem the best candidates for transplantation. Transplant-related mortality was 6% in the first EBMT report and 5.3% in the second one. No deaths were reported since 2001. Very high-intensity conditioning regimen is associated with higher risk of toxicity without significant increase in efficacy. The effects of transplantation and transplantation-related morbidity are dependent on patient-selection, time of transplantation and conditioning regimens used.This review is a comprehensive study of the results obtained in several single-center and multicenter studies. Patient characteristics, transplantations steps, toxicity and clinical outcome have been monitored and compared.

Antigen-specific therapies in multiple sclerosis

BACKGROUND

If found to be effective, antigen-specific therapies in MS hold the promise of selectively targeting pathogenic effector cells, while leaving the rest of immune system undisturbed.

OBJECTIVE

To review the principles and challenges of antigen-specific therapies of the past and those presently under development, and how the lessons learnt can guide us moving forward.

METHODS

We review past and current antigen-specific strategies for the treatment of MS, including their successes and challenges, as well as the lessons we have learnt from them about MS pathophysiology.

RESULTS

Several antigen-specific therapies may accomplish the desired balance between safety and efficacy, although significant challenges remain for this class of therapeutics.

Localized donor cells in brain of a Hunter disease patient after cord blood stem cell transplantation

The efficacy of hematopoietic stem cell transplantation (HSCT) for Hunter disease (deficiency of iduronate-2-sulfatase, IDS) remains unclear. We treated a 6-year-old male suffering from a severe type of Hunter disease with cord blood stem cell transplantation (CBSCT); however, he died at 10 months post-therapy due to a laryngeal post-transplantation lymphoproliferative disorder. During the follow-up period after CBSCT, his hyperactivity, estimated mental age, and brain MR findings had not improved. We assessed the efficacy of CBSCT by biochemical and pathological analyses of the autopsied tissues. There were many distended cells with accumulated substrate in the brain, but not in the liver. IDS enzyme activity in the cerebrum remained very low, although that in the liver reached about 40% of the normal control level. However, a variable number of tandem repeats analyses demonstrated a weak donor-derived band not only in the liver but also in the cerebrum. Furthermore, IDS-immunoreactivity in the liver was recognized broadly not only in Kupffer cells but also in hepatocytes. On the other hand, IDS-immunoreactivity was recognized exclusively in CD68-positive microglia/monocytes in the patient's brain; whereas that in the normal brain was also detected in neurons and oligodendrocytes. These donor-derived IDS-positive cells were predominantly localized in perivascular spaces and some of them were evidently present in the brain parenchyma. The efficacy of CBSCT was judged to be insufficient for the brain at 10 months post-therapy. However, the pathological detection of donor-derived cells in the brain parenchyma suggests the potential of HSCT for treatment of neurological symptoms in Hunter disease. This is the first neuropathological report documenting the distribution of donor-derived cells in the brain after CBSCT into a Hunter disease patient.

Multiple sclerosis: Hematopoietic stem cell transplantation: hope and hype

A trial of autologous hematopoietic stem cell transplantation to treat multiple sclerosis has yielded promising results, generating considerable interest within both the clinical literature and the mainstream press.the findings should, however, be interpreted with some caution, and larger, randomized trials will be required to establish the true efficacy of the approach.

Imaging outcomes for neuroprotection and repair in multiple sclerosis trials

Multiple sclerosis (MS) is commonly regarded as an inflammatory disease, but it also has a neurodegenerative component, which represents an additional target for treatment. The use of MRI to evaluate the inflammatory disease component in 'proof-of concept' clinical trials is well established, but no systematic assessment of imaging outcomes to evaluate neuroprotection or repair in MS has been performed. In this Review, we examine the potential of traditional and novel imaging parameters to serve as primary outcomes in phase II clinical trials of neuroprotective and reparative strategies in MS. We present the conclusions of an international meeting of imaging, clinical and statistical experts, as well as a review of relevant literature. The available imaging techniques are appraised in five categories of performance: pathological specificity, reproducibility, sensitivity to change, clinical relevance, and response to treatment. At present, the three most promising primary outcomes in phase II trials of neuroprotective and/or reparative strategies in MS are: changes in whole-brain volume to gauge general cerebral atrophy; T1 hypointensity and magnetization transfer ratio to monitor the evolution of lesion damage; and optical coherence tomography findings to evaluate the anterior visual pathway. Power calculations show that these outcome measures can be applied with attainable sample sizes.

The use of MR imaging as an outcome measure in multiple sclerosis clinical trials

MR imaging is an integral part of multiple sclerosis (MS) clinical trials. It provides the primary efficacy outcome of preliminary proof-of-concept studies and important corroborating data as secondary and exploratory outcomes in pivotal trials. At all stages of drug development, MR imaging provides important information on the kinetics and magnitude of treatment effect and insight into potential mechanisms of action. Attention to issues in scan acquisition, quantitative image processing, and statistical analysis is critical to generate high-quality data. Although it is unlikely that one single outcome measure can capture all aspects of the MS disease process, there is potential for MR imaging outcomes to evaluate inflammatory and degenerative components within clinical trials.