Autologous hematopoietic cell transplantation for multiple sclerosis: a systematic review

The Nitrogen Mustards

The nitrogen mustards are powerful cytotoxic and lymphoablative agents and have been used for more than 60 years. They are employed in the treatment of cancers, sarcomas, and hematologic malignancies. Cyclophosphamide, the most versatile of the nitrogen mustards, also has a place in stem cell transplantation and the therapy of autoimmune diseases. Adverse effects caused by the nitrogen mustards on the central nervous system, kidney, heart, bladder, and gonads remain important issues. Advances in analytical techniques have facilitated the investigation of the pharmacokinetics of the nitrogen mustards, especially the oxazaphosphorines, which are prodrugs requiring metabolic activation. Enzymes involved in the metabolism of cyclophosphamide and ifosfamide are very polymorphic, but a greater understanding of the pharmacogenomic influences on their activity has not yet translated into a personalized medicine approach. In addition to damaging DNA, the nitrogen mustards can act through other mechanisms, such as antiangiogenesis and immunomodulation. The immunomodulatory properties of cyclophosphamide are an area of current exploration. In particular, cyclophosphamide decreases the number and activity of regulatory T cells, and the interaction between cyclophosphamide and the intestinal microbiome is now recognized as an important factor. New derivatives of the nitrogen mustards continue to be assessed. Oxazaphosphorine analogs have been synthesized in attempts to both improve efficacy and reduce toxicity, with varying degrees of success. Combinations of the nitrogen mustards with monoclonal antibodies and small-molecule targeted agents are being evaluated. SIGNIFICANCE STATEMENT: The nitrogen mustards are important, well-established therapeutic agents that are used to treat a variety of diseases. Their role is continuing to evolve.

Intensive immunosuppression followed by autologous hematopoietic stem cell transplantation for the treatment of multiple sclerosis

Autologous hematopoietic stem cell transplantation (AHSCT) to treat multiple sclerosis (MS) has mostly been used in devastating cases as the last option to stop further neurological deterioration. However, evidence from several retrospective clinical trials indicates that young, less disabled patients with highly inflammatory active MS are the most likely to benefit from AHSCT, and after moving from high-intensity to nonmyeloablative procedures the tolerability of AHSCT has increased and its associated risk and mortality have declined considerably. Recent meta-analyses and randomized clinical trials show that AHSCT is more effective than currently approved disease-modifying therapies (DMTs), with suppression of disease activity in 70-90% of patients and long-term cessation of disease activity in two-thirds of treated patients. The rationale for AHSCT is to eliminate autoimmunity and achieve immune resetting by intense immunosuppression followed by infusion of autologous hematopoietic stem cells. Similar effects on the immune system have been suggested for cladribine and alemtuzumab treatment and, together with AHSCT, they constitute the induction or immune-reconstitution therapies for MS. Although, further randomized controlled trials of AHSCT for MS are needed, it has become clear that improved patient selection and lower intensity conditioning regimens have reduced AHSCT associated risks and mortality and strengthened the position of AHSCT among other DMTs. Do we have enough experience and scientific support for AHSCT in MS to move from an exclusive treatment for aggressive, treatment-resistant MS and acquire broader indications, similar to other effective DMTs?

Immunosuppression in relapsing remitting multiple sclerosis: moving towards personalized treatment

INTRODUCTION

Therapeutic armamentarium in Multiple Sclerosis (MS) has radically changed in the last few decades due to the development of disease modifying treatments (DMTs) with highly selective mechanisms of action.

AREAS COVERED

In this review, the authors will focus on the current role of immunosuppressive DMTs in the management of the relapsing-remitting form of MS (RRMS), moving from the rationale of its use and looking at the possibility to design an idealistic scenario of a personalized approach for each single patient.

EXPERT OPINION

Questions remain open about whether initial high-efficacy immunosuppressive DMTs improve long-term outcomes, whether prolonged exposure to these agents increases adverse events and what the strongest early surrogate markers are for predicting long-term treatment responses to high-efficacy drugs. In this way, the immunosuppressive DMTs, are used to hit the immune system early and hard with the idealistic goal of striking the autoimmune activities before the neurological damage becomes irreversible.

Efficacy and safety of autologous hematopoietic stem-cell transplantation in multiple sclerosis: a systematic review and meta-analysis

BACKGROUND

Autologous hematopoietic stem-cell transplantation (AHSCT) has been utilized as a treatment option for multiple sclerosis (MS) since 1995. However, this procedure has not been widely implemented in clinical practice owing to its mortality risk. Here, we conduct a meta-analysis to evaluate the long-term efficacy and safety of AHSCT in MS treatment, aiming to optimize the benefit/risk ratio of this therapeutic strategy.

METHODS

We searched the PubMed Web site and clinicaltrials.gov databases. The efficacy endpoints were progression-free survival (PFS) and disease activity-free survival. The safety outcomes were transplant-related mortality (TRM) and overall deaths.

RESULTS

Eighteen eligible studies with a total of 732 participants were enrolled. The PFS was 75% (95% CI, 0.69-0.81), and the estimate of disease activity-free survival was 61% with 48-month follow-up. Subgroups analysis showed that low- and intermediate-intensity regimens were associated with higher PFS 80%. Relapsing remitting MS (RRMS) benefited more from AHSCT than other MS subtypes with PFS 85%. Patients with Gd+ lesions at baseline MRI responded better to AHSCT with PFS 77%. The estimate of TRM was 1.34% (95% CI, 0.39-2.30), and the overall mortality was 3.58%. TRM was significantly higher in high-intensity regimen studies (3.13%) and in older studies (1.93%) performed before 2006.

CONCLUSIONS

This meta-analysis provides evidences that AHSCT can induce long-term remissions for MS patients with a high degree of safety. We indicate low- and intermediate-intensity regimens and RRMS patients with the presence of Gd+ lesions at baseline MRI can obtain the optimal benefit/risk ratio from AHSCT.

[Indications and follow-up for autologous hematopoietic stem cell transplantation in multiple sclerosis: Guidelines from the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC) in association with the Francophone Society of Multiple Sclerosis]

The Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC) organized the 8th allogeneic hematopoietic stem cell transplantation clinical practices harmonization workshop series in September 2017 in Lille, France. In this article we give the indications of autologous stem cell transplantation in multiple sclerosis as well as recommendations regarding post-transplant follow-up of patients under the hospice of the SFGM-TC and the Francophone Society of Multiple Sclerosis.

Current Therapeutic Approaches in Leukodystrophies: A Review

Leukodystrophies are a heterogeneous class of genetic diseases affecting the white matter in the central nervous system with a broad range of clinical manifestations and a frequently progressive course. An interest in precision medicine has emerged over the last several decades, and biomedical research in leukodystrophies has made exciting advances along this front through therapeutic target discovery and novel disease model systems. In this review, we discuss current and emerging therapeutic approaches in leukodystrophies, including gene therapy, antisense oligonucleotide therapy, CRISPR/CAS-based gene editing, and cell and stem cell based therapies.

Long-term follow-up more than 10 years after HSCT: a monocentric experience

BACKGROUND

Autologous hematopoietic stem cell transplantation (aHSCT) is used in aggressive relapsing and progressive multiple sclerosis (MS). The multicentre studies and case series reported have relatively short follow-up.

AIM

To evaluate long-term effect and safety of HSCT in MS.

MATERIALS AND METHODS

Patients referred to the MS centre of Cagliari and undergoing HSCT were included. Variations in relapses and EDSS before and after HSCT were evaluated by Wilcoxon test. A descriptive analysis was made for other clinical data.

RESULTS

Nine patients (female 6, males 3; 5 relapsing-remitting, 2 secondary progressive, 1 primary progressive, and 1 progressive relapsing) performed HSCT (1999-2006). The median follow-up was 11 years (11-18). Eight patients underwent aHSCT, seven using a low intensity conditioning regimen, and one an intermediate intensity. The primary progressive underwent allogeneic HSCT, due to onco hematological disease. The relapses number decreased in the 2 years following the procedure compared to the two preceding years (p = 0.041). New relapses or disease progressions were observed after a range of 7 (low intensity regimen)-118 (intermediate intensity) months. At last follow-up, the EDSS was stable in two patients, improved in two, and worse in five (maximum 2 EDSS in one patient). Six patients showed new lesions, and seven gadolinium-enhancing on brain MRI after a mean of 23.3 and 19.8 months, respectively. Two serious adverse events were reported: melanoma, and progressive multifocal leukoencephalopathy.

CONCLUSIONS AND DISCUSSION

Our results confirm in a long follow-up the efficacy of HSCT in reducing relapses and disability progression. The risk/benefit profile is better for intermediate intensity regimens.

Stem Cells and Other Emerging Agents as Innovative "Drugs" in Neurodegenerative Diseases: Benefits and Limitations

The brain has a limited process of repair/regeneration linked to the restricted and localized activity of neuronal stem cells. Consequently, it shows a reduced capacity to counteract the age-related loss of neural and glial cells and to repair the consequent injuries/lesions of nervous system. This progressively determines nervous dysfunction and onset/progression of neurodegenerative diseases, which represent a serious social (and economic) problem of our populations. Thus, the research of efficient treatments is encouraged. Stem cell therapy might represent a solution. Today, it, indeed, represents the object of intensive research with the hope of using it, in a near future, as effective therapy for these diseases and preventive treatment in susceptible individuals. Here, we report and discuss the data of the recent studies on this field, underling the obstacles and benefits. We also illustrate alternative measures of intervention, which represent another parallel aim for the care of neurodegenerative pathology-affected individuals. Thus, the road for delaying or retarding these diseases appears hard and long, but the advances might be different.

Autologous haematopoietic stem cell transplantation for treatment of multiple sclerosis

Autologous haematopoietic stem cell transplantation (AHSCT) is a multistep procedure that enables destruction of the immune system and its reconstitution from haematopoietic stem cells. Originally developed for the treatment of haematological malignancies, the procedure has been adapted for the treatment of severe immune-mediated disorders. Results from ∼20 years of research make a compelling case for selective use of AHSCT in patients with highly active multiple sclerosis (MS), and for controlled trials. Immunological studies support the notion that AHSCT causes qualitative immune resetting, and have provided insight into the mechanisms that might underlie the powerful treatment effects that last well beyond recovery of immune cell numbers. Indeed, studies have demonstrated that AHSCT can entirely suppress MS disease activity for 4-5 years in 70-80% of patients, a rate that is higher than those achieved with any other therapies for MS. Treatment-related mortality, which was 3.6% in studies before 2005, has decreased to 0.3% in studies since 2005. Current evidence indicates that the patients who are most likely to benefit from and tolerate AHSCT are young, ambulatory and have inflammatory MS activity. Clinical trials are required to rigorously test the efficacy, safety and cost-effectiveness of AHSCT against highly active MS drugs.

Autologous hematopoietic stem cell transplantation in relapsing-remitting multiple sclerosis: comparison with secondary progressive multiple sclerosis

The main objective of our work is to describe the long-term results of myeloablative autologous hematopoietic stem cell transplant (AHSCT) in multiple sclerosis patients. Patients that failed to conventional therapies for multiple sclerosis (MS) underwent an approved protocol for AHSCT, which consisted of peripheral blood stem cell mobilization with cyclophosphamide and granulocyte colony-stimulating factor (G-CSF), followed by a conditioning regimen of BCNU, Etoposide, Ara-C, Melphalan IV, plus Rabbit Thymoglobulin. Thirty-eight MS patients have been transplanted since 1999. Thirty-one patients have been followed for more than 2 years (mean 8.4 years). There were 22 relapsing-remitting multiple sclerosis (RRMS) patients and 9 secondary progressive multiple sclerosis (SPMS) patients. No death related to AHSCT. A total of 10 patients (32.3%) had at least one relapse during post-AHSCT evolution, 6 patients in the RRMS group (27.2%) and 4 in the SPMS group (44.4%). After AHSCT, 7 patients (22.6%) experienced progression of disability, all within SP form. By contrast, no patients with RRMS experienced worsening of disability after a median follow-up of 5.4 years, 60% of them showed a sustained reduction in disability (SRD), defined as the improvement of 1.0 point in the expanded disability status scale (EDSS) sustains for 6 months (0.5 in cases of EDSS ≥ 5.5). The only clinical variable that predicted a poor response to AHSCT was a high EDSS in the year before transplant. AHSCT using the BEAM-ATG scheme is safe and efficacious to control the aggressive forms of RRMS.

Autologous hematopoietic cell transplantation in multiple sclerosis

INTRODUCTION

Autologous haematopoietic cell transplantation (AHCT) is an evolving treatment avenue in multiple sclerosis (MS), which may be highly effective in controlling disease activity and improving disability. However, AHCT is associated with intrinsic toxicities and risks compared with conventional therapies. With growing experience in patient selection and treatment delivery, AHCT is increasingly considered an option in patients with aggressive disease that's responding poorly to disease modifying therapy. Areas covered: This article provides an introduction to AHCT and looks at its development as a treatment for MS over the last 20 years. It also highlights potential mechanisms of action, patient selection, and future trends for this treatment approach. Expert opinion: Currently published data suggest that AHCT's use is associated with significant reduction in MS disease activity and marked improvement in disability when used in patients with highly active relapsing remitting disease. Its long term safety and efficacy have not been fully evaluated but as increasing clinical trial data are published, its use is likely to grow. Further randomised controlled studies are needed to compare AHCT with standard disease modifying therapies and to optimise transplant regimens. Mechanistic studies may provide potential markers for response and a better understanding of disease pathogenesis.

The role of stem cell therapy in multiple sclerosis: An overview of the current status of the clinical studies

The complexity of multiple sclerosis (MS) and the incompetence of a large number of promised treatments for MS urge us to plan new and more effective therapeutic approaches that aim to suppress ongoing autoimmune responses and induction of local endogenous regeneration. Emerging data propose that hematopoietic, mesenchymal, and neural stem cells have the potential to restore self-tolerance, provide in situ immunomodulation and neuroprotection, as well as promote regeneration. Thus, in this article, we will first provide an overview of the cell sources for proposed mechanisms that contribute to the beneficial effects of stem cell transplantation, the ideal route and/or timing of stem cell-based therapies for each main stem cell group, and finally, an overview of the current status of stem cell research in clinical trial stages in MS by comparable and healthy therapeutic effects of different stem cell therapies for MS patients.

Current Indications, Techniques, and Imaging Findings of Stem Cell Treatment and Bone Marrow Transplant

The role of stem cell therapy in the treatment of hematologic and nonhematologic conditions is ever increasing. A thorough knowledge of the applications of stem cells and transplant physiology is essential for understanding the imaging manifestations. Stem cell imaging includes molecular imaging, and diagnostic and interventional radiology. It is possible to make a diagnosis of various complications and diseases associated with stem cell transplant. This article presents a simplified overview of stem cell applications and techniques with focus on hematopoietic stem cell transplant imaging.

Treatment of refractory ITP and Evans syndrome by haematopoietic cell transplantation: is it indicated, and for whom?

Several lines of therapy have been established for patients with immune thrombocytopenia (ITP) and Evans syndrome. However, these therapies generally require prolonged administration, lead to profound immunosuppression and increased infectious risk, and are often poorly tolerated. While most patients with these disorders will respond to first-line steroid therapy, others will prove refractory or intolerant to multiple treatments. In these patients (and possibly even selected patients who are not considered refractory), autologous or allogeneic haematopoietic stem cell transplantation (HCT) may provide definitive therapy. We review the literature on the treatment of ITP and Evans syndrome with HCT and discuss its use in the management of these disorders. We also pose, for the purpose of discussion, research questions that will be important to address if HCT is to be considered a viable option for more patients with these diseases.

Autologous bone marrow transplantation for the treatment of multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system and represents one of the leading causes of neurologic disability in young adults. Current treatments for MS have shown limited efficacy in patients with either a progressive or an aggressive disease course. Hematopoietic stem cell transplantation (HSCT) has been proposed to control or even cure refractory cases of MS. Indeed, HSCT is able to temporarily eradicate the autoreactive cells and to reset the aberrant immune response to self-antigens. In the last decade, owing to the growing experience in selecting the most appropriate patients to transplant and the recent advances in chemotherapeutic and support regimens, the transplant-related mortality of autologous HSCT in MS patients dropped down to 1,3 % and the progression-free survival ranges from 47 % to 100 %. Altogether, these data support autologous HSCT as a possible second-line therapy for refractory MS.

Clinical trials in progressive multiple sclerosis: lessons learned and future perspectives

Progressive multiple sclerosis is characterised clinically by the gradual accrual of disability independent of relapses and can occur with disease onset (primary progressive) or can be preceded by a relapsing disease course (secondary progressive). An effective disease-modifying treatment for progressive multiple sclerosis has not yet been identified, and so far the results of clinical trials have generally been disappointing. Ongoing advances in the knowledge of pathogenesis, in the identification of novel targets for neuroprotection, and in improved outcome measures could lead to effective treatments for progressive multiple sclerosis. In this Series paper, we summarise the lessons learned from completed clinical trials and perspectives from trials in progress in progressive multiple sclerosis. We review promising clinical, imaging, and biological markers, along with novel designs, for clinical trials. The use of more refined outcomes and truly neuroprotective drugs, coupled with more efficient trial design, has the capacity to deliver a new era of therapeutic discovery in this challenging area.

Disease-modifying treatments for progressive multiple sclerosis

The last 20 years have seen major progress in the treatment of relapsing-remitting multiple sclerosis (RRMS) using a variety of drugs targeting immune dysfunction. In contrast, all clinical trials of such agents in primary progressive multiple sclerosis (PPMS) have failed and there is limited evidence of their efficacy in secondary progressive disease. Evolving concepts of the complex interplay between inflammatory and neurodegenerative processes across the course of multiple sclerosis (MS) may explain this discrepancy. This paper will provide an up-to-date overview of the rationale and results of the published clinical trials that have sought to alter the trajectory of both primary and secondary MS, considering studies involving drugs with a primary immune target and also those aiming for neuroprotection. Future areas of study will be discussed, building on these results combined with the experience of treating RRMS and new concepts emerging from laboratory science and animal models.

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.

Management of secondary progressive multiple sclerosis: prophylactic treatment-past, present, and future aspects

OPINION STATEMENT

Whereas the number of treatment options in relapsing-remitting multiple sclerosis (RRMS) is growing constantly, alternatives are rare in the case of secondary-progressive multiple sclerosis (SPMS). Besides mitoxantrone in North America and Europe, interferon beta-1b and beta-1a are approved for treatment in Europe. Glucocorticosteroids, azathioprine, intravenous immunoglobulins (IVIG) and cyclophosphamide (CYC), although not approved, are commonly utilized in SPMS. Currently monoclonal antibodies (mab), and masitinib are under examination for treatment for SPMS. Hematopoietic stem cell transplantation and immunoablative stem cell transplantation are therapies with the aim of reconstitution of the immune system. This review gives information on the different therapeutics and the trials that tested them. Pathophysiological considerations are presented in view of efficacy of the therapeutics. In addition, therapeutics that showed no efficacy in trials or with unacceptable side effects are topics of this review.

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.

A prospective, randomized, controlled trial of autologous haematopoietic stem cell transplantation for aggressive multiple sclerosis: a position paper

Background:

Haematopoietic stem cell transplantation (HSCT) has been tried in the last 15 years as a therapeutic option in patients with poor-prognosis autoimmune disease who do not respond to conventional treatments. Worldwide, more than 600 patients with multiple sclerosis (MS) have been treated with HSCT, most of them having been recruited in small, single-centre, phase 1–2 uncontrolled trials. Clinical and magnetic resonance imaging outcomes from case series reports or Registry-based analyses suggest that a major response is achieved in most patients; quality and duration of response are better in patients transplanted during the relapsing–remitting phase than in those in the secondary progressive stage.

Objectives:

An interdisciplinary group of neurologists and haematologists has been formed, following two international meetings supported by the European and American Blood and Marrow Transplantation Societies, for the purpose of discussing a controlled clinical trial, to be designed within the new scenarios of evolving MS treatments.

Conclusions:

Objectives of the trial, patient selection, transplant technology and outcome assessment were extensively discussed. The outcome of this process is summarized in the present paper, with the goal of establishing the background and advancing the development of a prospective, randomized, controlled multicentre trial to assess the clinical efficacy of HSCT for the treatment of highly active MS.

Autologous haematopoietic stem cell transplantation with an intermediate intensity conditioning regimen in multiple sclerosis: the Italian multi-centre experience

BACKGROUND

Over recent years numerous patients with severe forms of multiple sclerosis (MS) refractory to conventional therapies have been treated with intense immunosuppression followed by autologous haematopoietic stem cell transplantation (AHSCT). The clinical outcome and the toxicity of AHSCT can be diverse, depending on the various types of conditioning protocols and on the disease phase.

OBJECTIVES

To report the Italian experience on all the consecutive patients with MS treated with AHSCT with an intermediate intensity conditioning regimen, named BEAM/ATG, in the period from 1996 to 2008.

METHODS

Clinical and magnetic resonance imaging outcomes of 74 patients were collected after a median follow-up period of 48.3 (range = 0.8-126) months.

RESULTS

Two patients (2.7%) died from transplant-related causes. After 5 years, 66% of patients remained stable or improved. Among patients with a follow-up longer than 1 year, eight out of 25 subjects with a relapsing-remitting course (31%) had a 6-12 months confirmed Expanded Disability Status Scale improvement > 1 point after AHSCT as compared with one out of 36 (3%) patients with a secondary progressive disease course (p = 0.009). Among the 18 cases with a follow-up longer than 7 years, eight (44%) remained stable or had a sustained improvement while 10 (56%), after an initial period of stabilization or improvement with median duration of 3.5 years, showed a slow disability progression.

CONCLUSIONS

This study shows that AHSCT with a BEAM/ATG conditioning regimen has a sustained effect in suppressing disease progression in aggressive MS cases unresponsive to conventional therapies. It can also cause a sustained clinical improvement, especially if treated subjects are still in the relapsing-remitting phase of the disease.

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.