Hematopoietic stem cell transplantation for multiple sclerosis.

Over the past decades, several effective disease-modifying therapies have been approved for the treatment of multiple sclerosis (MS); however, achieving long-term disease remission remains challenging, particularly for patients with aggressive forms of MS. Intense immunosuppression followed by hematopoietic stem cell transplantation (HSCT) has been increasingly explored as a treatment strategy for aggressive MS. To date, more than 1800 MS patients have undergone HSCT worldwide. In this chapter, we provide a brief overview of the HSCT procedure, with a special focus on the unique considerations for transplanting MS patients (such as fertility preservation, prior therapy washout, and posttransplant monitoring). We also discuss the main evidence of efficacy and safety of the procedure in this context, as well as present preliminary data on the impact of HSCT on cerebrospinal fluid findings, magnetic resonance imaging metrics, and novel serum biomarkers of neurodegeneration and demyelination. In addition, we provide recommendations for patient selection from international guidelines.

HSCT for stiff person syndrome and myasthenia gravis.

Recent advances in neuroimmunology have shed light on the pathogenic mechanisms underlying rare neuroimmunologic conditions such as myasthenia gravis (MG) and stiff person syndrome (SPS). Despite the rarity of these conditions, their complex manifestations and potential for irreversible disability necessitate effective therapeutic strategies. This chapter reviews the current understanding of the safety and efficacy of hematopoietic stem cell transplantation (HSCT) in MG and SPS. Several case reports and retrospective studies have demonstrated promising outcomes following HSCT in refractory MG and SPS, with significant clinical improvement and even discontinuation of chronic immunomodulatory therapy in some cases. Furthermore, HSCT may offer insights into the underlying pathophysiologic mechanisms of these conditions, particularly the role of cellular immunity. Although more research is needed to fully understand the impact of HSCT on disease pathology and outcomes, current evidence suggests that HSCT could be a valuable therapeutic option for patients with refractory MG and SPS.

Introduction to HSCT for neurologic diseases.

The use of hematopoietic stem cell transplantation (HSCT) as a treatment option for severe autoimmune diseases originated from animal studies, with promising results in human patients reported through clinical responses seen in individuals who underwent HSCT for other reasons. Currently, over 3800 HSCT procedures have been performed specifically for autoimmune disorders and the procedure has become a standard of care for conditions such as multiple sclerosis and systemic sclerosis. Despite the growing interest among the neurology community in using HSCT to treat refractory autoimmune disorders, several obstacles must still be overcome for the procedure to become widely accepted. These include increasing the safety of the procedure, determining the most effective conditioning regimen, fostering collaboration between neurology and hematology teams, and providing robust phase III study data to demonstrate the superiority of HSCT over standard immunotherapy. This Handbook aims to provide a valuable resource for all those involved in the care of patients undergoing HSCT, and we hope it will contribute to the efforts to find the correct placement of HSCT in the therapeutic strategy of the treatment of autoimmune disorders of the nervous system.

Ongoing randomized clinical trials on HSCT in multiple sclerosis.

Autologous hematopoietic stem cell transplantation (AHSCT) is emerging as a potent treatment for highly active relapsing remitting multiple sclerosis (RRMS), potentially surpassing the efficacy of traditional disease-modifying therapies (DMTs). Phase II and III randomized controlled trials (RCTs) have demonstrated AHSCT's superiority in reducing relapse rates and delaying disability progression compared to standard DMTs. Despite the evolution of treatment guidelines, questions persist regarding patient selection criteria and optimal conditioning regimens. Notably, ongoing clinical trials in the United Kingdom, the United States, Italy, and Norway aim to address these uncertainties by evaluating the safety, efficacy, and long-term outcomes of AHSCT vs. high efficacy DMTs in both DMT-experienced and treatment-naïve patients with active RRMS or aggressive multiple sclerosis (MS). These trials promise to provide valuable insights into the positioning of AHSCT within the treatment landscape of MS.

Relapsing meningitis and limbic encephalitis in anti-AQP4-Ab-associated neuromyelitis optica spectrum disorder.

OBJECTIVES: neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune disease mainly affecting optic nerves and the spinal cord. Due to the potentially irreversible tissue damage, prevention of relapses is of utmost importance. METHODS: We describe the atypical clinical course and pathology results of a patient with anti-aquaporin-4 antibody (anti-AQP4-Ab)-associated NMOSD who developed aseptic meningitis followed by limbic-encephalitis-like presentation with extensive brain lesions upon treatment with rituximab and tocilizumab. RESULTS: The patient developed subacute cognitive decline with magnetic resonance imaging (MRI) evidence of extensive brain white matter lesions. In the hypothesis of an opportunistic brain infection, she underwent brain biopsy of the temporal pole. Pathology results revealed typical NMOSD findings with complement activation, supporting the hypothesis of an atypical presentation of anti-AQP-Ab-associated NMOSD. Accordingly, treatment with the complement-targeting drug eculizumab was started, leading to a dramatic clinical and MRI improvement. DISCUSSION: aseptic meningitis and limbic encephalitis could represent a rare phenotype of anti-AQP4-Ab-associated NMOSD.

Disease-modifying therapies in managing disability worsening in paediatric-onset multiple sclerosis: a longitudinal analysis of global and national registries.

BACKGROUND: High-efficacy disease-modifying therapies have been proven to slow disability accrual in adults with relapsing-remitting multiple sclerosis. However, their impact on disability worsening in paediatric-onset multiple sclerosis, particularly during the early phases, is not well understood. We evaluated how high-efficacy therapies influence transitions across five disability states, ranging from minimal disability to gait impairment and secondary progressive multiple sclerosis, in people with paediatric-onset multiple sclerosis. METHODS: Longitudinal data were obtained from the international MSBase registry, containing data from people with multiple sclerosis from 151 centres across 41 countries, and the Italian Multiple Sclerosis and Related Disorders Register, containing data from people with multiple sclerosis from 178 Italian multiple sclerosis centres. People younger than 18 years at the onset of multiple sclerosis symptoms were included, provided they had a confirmed diagnosis of relapsing-remitting multiple sclerosis and at least four Expanded Disability Status Scale (EDSS) scores recorded within 12-month intervals. The primary outcome was the time to change in disability state: minimal disability (EDSS scores 0, 1·0, and 1·5), mild disability (EDSS scores 2·0 and 2·5), moderate disability (EDSS scores 3·0 and 3·5), gait impairment (EDSS scores ≥4·0), and clinician diagnosed secondary progressive multiple sclerosis. A multi-state model was constructed to simulate the natural course of multiple sclerosis, modelling the probabilities of both disability worsening and improvement simultaneously. The impact of high-efficacy disease-modifying therapies (alemtuzumab, cladribine, daclizumab, fingolimod, mitoxantrone, natalizumab, ocrelizumab, rituximab, or autologous haematopoietic stem cell transplantation) and low-efficacy disease-modifying therapies (dimethyl fumarate, glatiramer acetate, interferon beta, or teriflunomide), compared with no treatment, on the course of disability was assessed. Apart from recruitment, individuals with lived experience of multiple sclerosis were not involved in the design and conduct of this study. FINDINGS: A total of 5224 people (3686 [70·6%] female and 1538 [29·4%] male) with mean age at onset of multiple sclerosis 15·24 years (SD 2·52) were included. High-efficacy therapies reduced the hazard of disability worsening across the disability states. The largest reduction (hazard ratio 0·41 [95% CI 0·31-0·53]) was observed in participants who were treated with high-efficacy therapies while in the minimal disability state, compared with those remained untreated. The benefit of high-efficacy therapies declined with increasing disability. Young people with minimal disability who received low-efficacy therapy also experienced a reduced hazard (hazard ratio 0·65 [95% CI 0·54-0·77]) of transitioning to mild disability, in contrast to those who remained untreated. INTERPRETATION: Treatment of paediatric-onset relapsing-remitting multiple sclerosis with high-efficacy therapy substantially reduces the risk of reaching key disability milestones. This reduction in risk is most pronounced among young people with minimal or mild disability when treatment began. Children with relapsing-remitting multiple sclerosis should be treated early with high-efficacy therapy, before developing significant neurological impairments, to better preserve their neurological capacity. FUNDING: National Health and Medical Research Council, Australia; MSBase Foundation Fellowship; MS Australia Postdoctoral Fellowship.

An aggressive form of MOGAD treated with aHSCT: A case report.

BACKGROUND: Although myelin-oligodendrocyte-glycoprotein (MOG)-antibody-associated disease (MOGAD) has been considered a more favorable demyelinating central nervous system disorder, recent data evidence that some patients might experience severe relapses and high disability. Actual treatment-options are acquired mostly from anti-aquaporin-4-antibody-positive neuromyelitis optica spectrum disorder and rely on clinical experience. Therefore, treatment of aggressive forms of MOGAD can be challenging. OBJECTIVES AND METHODS: To describe a patient with an aggressive MOGAD treated with autologous hematopoietic stem cell transplantation (aHSCT). RESULTS: A 56-year-old man was diagnosed with MOGAD in 2017 because of right optic-neuritis and anti-MOG-antibody positivity. In the following 2 years, he experienced two optic neuritis with good recovery after high-dose steroid. At the end of 2019, he presented sensory and motor impairment at lower limbs with evidence of several spinal, longitudinally extended, tumefactive inflammatory lesions. Despite sequential treatment with rituximab and tocilizumab alongside high-dose steroid, intravenous immunoglobulins and plasma-exchange, he experienced several clinical relapses and exhibited persistent magnetic resonance activity. He was finally addressed to intense immunosuppression with myeloablative conditioning regimen followed by autologous hematopoietic stem cell transplantation (aHSCT). After 2 years follow-up, he is free from disease-activity. CONCLUSIONS: In a patient affected by aggressive, treatment-refractory MOGAD, aHSCT resulted as safe and was able to suppress disease-activity for over 2 years.

Safety of anti-varicella zoster virus vaccination in patients with multiple sclerosis treated with natalizumab: A case series.

The vaccination with live attenuated vaccines is generally not recommended during natalizumab (NTZ), as it is included among immunosuppressive/immunomodulating therapies. Nevertheless, considering the lack of evidence of a non-Central Nervous System (CNS) immunosuppressive effect of NTZ, after a risk/benefit evaluation, we decided to vaccinate four multiple sclerosis (MS) patients (three with an indication to switch to ocrelizumab for high-risk Progressive Multifocal Leukoencephalopathy (PML) and one for pregnancy planning). No vaccine-related adverse events of any type nor varicella zoster virus (VZV) infections were observed. To the best of our knowledge, these case series represent the first description of the good safety profile of anti-VZV vaccination in MS patients during NTZ treatment.

Brain FDG-PET findings in chimeric antigen receptor T-cell therapy neurotoxicity for diffuse large B-cell lymphoma.

BACKGROUND AND PURPOSE: Chimeric antigen receptor (CAR) T-cell therapy is potentially associated with treatment-related toxicities mainly consisting of cytokine release syndrome (CRS) and immune-effector cell-associated neurotoxicity syndrome (ICANS). We evaluated brain metabolic correlates of CRS with and without ICANS in diffuse large B-cell lymphoma patients treated with CAR-T. METHODS: Twenty-one refractory DLCBLs underwent whole-body and brain [18 F]-fluorodeoxyglucose (FDG) PET before and 30 days after treatment with CAR-T. Five patients did not develop inflammatory-related side effects, 11 patients developed CRS, while in 5 patients CRS evolved in ICANS. Baseline and post-CAR-T brain FDG-PET were compared with a local controls dataset to identify hypometabolic patterns both at single-patient and group levels (p < .05 after correction for family-wise error [FWE). Metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were computed on baseline FDG-PET and compared between patients' subgroups (t-test). RESULTS: ICANS showed an extended and bilateral hypometabolic pattern mainly involving the orbitofrontal cortex, frontal dorsolateral cortex, and anterior cingulate (p < .003 FWE-corrected). CRS without ICANS showed significant hypometabolism in less extended clusters mainly involving bilateral medial and lateral temporal lobes, posterior parietal lobes, anterior cingulate, and cerebellum (p < .002 FWE-corrected). When compared, ICANS showed a more prominent hypometabolism in the orbitofrontal and frontal dorsolateral cortex in both hemispheres than CRS (p < .002 FWE-corrected). Mean baseline MTV and TLG were significantly higher in ICANS than CRS (p < .02). CONCLUSIONS: Patients with ICANS are characterized by a frontolateral hypometabolic signature coherently with the hypothesis of ICANS as a predominant frontal syndrome and with the more prominent susceptibility of frontal lobes to cytokine-induced inflammation.

Hematopoietic Stem Cell Transplantation in People With Active Secondary Progressive Multiple Sclerosis.

BACKGROUND AND OBJECTIVES: Uncontrolled evidence suggests that autologous hematopoietic stem cell transplantation (AHSCT) can be effective in people with active secondary progressive multiple sclerosis (SPMS). In this study, we compared the effect of AHSCT with that of other anti-inflammatory disease-modifying therapies (DMTs) on long-term disability worsening in active SPMS. METHODS: We collected data from the Italian Bone Marrow Transplantation Study Group and the Italian Multiple Sclerosis Register. Patients were considered eligible if treatment had been started after the diagnosis of SPMS. Disability worsening was assessed by the cumulative proportion of patients with a 6-month confirmed disability progression (CDP) according to the Expanded Disability Status Scale (EDSS) score. Key secondary endpoints were the EDSS time trend after treatment start and the prevalence of disability improvement over time. Time to first CDP was assessed by means of proportional hazard Cox regression models. A linear mixed model with a time × treatment group interaction was used to assess the longitudinal EDSS time trends. Prevalence of improvement was estimated using a modified Kaplan-Meier estimator and compared between groups by bootstrapping the area under the curve. RESULTS: Seventy-nine AHSCT-treated patients and 1975 patients treated with other DMTs (beta interferons, azathioprine, glatiramer-acetate, mitoxantrone, fingolimod, natalizumab, methotrexate, teriflunomide, cyclophosphamide, dimethyl fumarate, and alemtuzumab) were matched to reduce treatment selection bias using propensity score and overlap weighting approaches. Time to first CDP was significantly longer in transplanted patients (hazard ratio [HR] = 0.50; 95% CI = 0.31-0.81; p = 0.005), with 61.7% of transplanted patients free from CPD at 5 years. Accordingly, EDSS time trend over 10 years was higher in patients treated with other DMTs than in AHSCT-treated patients (+0.157 EDSS points per year compared with -0.013 EDSS points per year; interaction p < 0.001). Patients who underwent AHSCT were more likely to experience a sustained disability improvement: 34.7% of patients maintained an improvement (a lower EDSS than baseline) 3 years after transplant vs 4.6% of patients treated by other DMTs (p < 0.001). DISCUSSION: The use of AHSCT in people with active SPMS is associated with a slowing of disability progression and a higher likelihood of disability improvement compared with standard immunotherapy. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that autologous hematopoietic stem cell transplants prolonged the time to CDP compared with other DMTs.

Anti-SARS-CoV-2 T-stem cell memory persists in ocrelizumab-treated MS patients.

BACKGROUND: Development of long-lasting anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) T-cell responses in persons with multiple sclerosis (pwMS) treated with ocrelizumab is questioned. OBJECTIVE: Investigate antiviral T-cell responses after infection with SARS-CoV-2 in ocrelizumab-treated pwMS. Control groups included ocrelizumab-treated pwMS without SARS-CoV-2 infection, and non-MS individuals with and without SARS-CoV-2 infection. METHODS: Peripheral blood mononuclear cells were stimulated with SARS-CoV-2 peptide pools and T-cell reactivity was assessed by ELISPOT for interferon (IFN)-γ detection, and by multiparametric fluorescence-activated cell sorting (FACS) analyses for assessment and characterization of T-cell activation. RESULTS: ELISPOT assay against the spike and the N protein of SARS-CoV-2 displayed specific T-cell reactivity in 28/29 (96%) pwMS treated with ocrelizumab and infected by SARS-CoV-2, similar to infected persons without MS. This reactivity was present 1 year after infection and independent from the time of ocrelizumab infusion. FACS analysis following stimulation with SARS-CoV-2 peptide pools showed the presence of activation-induced markers (AIMs) in both CD4+ and CD8+ T-cell subsets in 96% and 92% of these individuals, respectively. Within naïve AIM+ CD4+ and CD8+ T-cells, we detected T memory stem cells, suggesting the acquisition of long-term memory. CONCLUSIONS: B-cell depletion using ocrelizumab does not impair the development of long-lasting anti-SARS-CoV-2 T-cell responses.

mRNA-COVID19 Vaccination Can Be Considered Safe and Tolerable for Frail Patients.

Background: Frail patients are considered at relevant risk of complications due to coronavirus disease 2019 (COVID-19) infection and, for this reason, are prioritized candidates for vaccination. As these patients were originally not included in the registration trials, fear related to vaccine adverse events and disease worsening was one of the reasons for vaccine hesitancy. Herein, we report the safety profile of the prospective, multicenter, national VAX4FRAIL study (NCT04848493) to evaluate vaccines in a large trans-disease cohort of patients with solid or hematological malignancies and neurological and rheumatological diseases. Methods: Between March 3 and September 2, 2021, 566 patients were evaluable for safety endpoint: 105 received the mRNA-1273 vaccine and 461 the BNT162b2 vaccine. Frail patients were defined per protocol as patients under treatment with hematological malignancies (n = 131), solid tumors (n = 191), immune-rheumatological diseases (n = 86), and neurological diseases (n = 158), including multiple sclerosis and generalized myasthenia. The impact of the vaccination on the health status of patients was assessed through a questionnaire focused on the first week after each vaccine dose. Results: The most frequently reported moderate-severe adverse events were pain at the injection site (60.3% after the first dose, 55.4% after the second), fatigue (30.1%-41.7%), bone pain (27.4%-27.2%), and headache (11.8%-18.9%). Risk factors associated with the occurrence of severe symptoms after vaccine administration were identified through a multivariate logistic regression analysis: age was associated with severe fever presentation (younger patients vs. middle-aged vs. older ones), female individuals presented a higher probability of severe pain at the injection site, fatigue, headache, and bone pain; and the mRNA-1237 vaccine was associated with a higher probability of severe pain at the injection site and fever. After the first dose, patients presenting a severe symptom were at a relevant risk of recurrence of the same severe symptom after the second one. Overall, 11 patients (1.9%) after the first dose and 7 (1.2%) after the second one required postponement or suspension of the disease-specific treatment. Finally, two fatal events occurred among our 566 patients. These two events were considered unrelated to the vaccine. Conclusions: Our study reports that mRNA-COVID-19 vaccination is safe also in frail patients; as expected, side effects were manageable and had a minimum impact on patient care path.

Impact of Natural Killer (NK) Cells on Immune Reconstitution, and Their Potential as a Biomarker of Disease Activity, in Alemtuzumab-Treated Patients with Relapsing Remitting Multiple Sclerosis: An Observational Study.

BACKGROUND: Defining immune mechanisms leading to multiple sclerosis (MS) is difficult, due to the great inter-individual difference in immune system responses. The anti-CD52 antibody alemtuzumab transiently abolishes differences in immune parameters among individuals, allowing analysis of subsequent immune cell repopulation patterns, and their possible role in MS. OBJECTIVE: To evaluate the correlation between innate and adaptive immune cell subsets and disease activity in MS in the context of treatment with alemtuzumab. METHODS: A two-center observational cohort of patients treated with alemtuzumab underwent immune profiling of T, B, and natural killer (NK) cells, biomarker, clinical and radiological follow-up. RESULTS: After treatment, the percentage of NK and B cells increased; NK, T- and B-cell populations underwent a profound rearrangement. Within the effector T-cell compartment, treatment led to a transient decrease, followed by an increase, of T-helper 1 cells, and to a transient decrease of T-helper 17 cells. Within the T-regulatory compartment, naïve T-regulatory cells increased. Within the B-cell compartment, memory B cells and mature B cells decreased, whereas transitional B cells increased. Within the NK cell compartment, CD56bright NK cells increased. Subjects without disease activity had a greater decrease in serum NfL and greater NK cell/CD3+ T cell ratio. NK cell numbers at baseline and after treatment influenced reconstitution of T and B cells, being inversely correlated with the reconstitution of proinflammatory CD3+ T cells and mature B cells, and directly correlated to the increase in transitional B cells. CONCLUSIONS: The results of this study provide novel evidence that NK cells influence reconstitution of adaptive immune cells upon alemtuzumab and that patients with a successful response to alemtuzumab have an early immune reconstitution dominated by NK cells.

PML risk is the main factor driving the choice of discontinuing natalizumab in a large multiple sclerosis population: results from an Italian multicenter retrospective study.

BACKGROUND: Natalizumab (NTZ) is an effective treatment for relapsing-remitting multiple sclerosis (RRMS). However, patients and physicians may consider discontinuing NTZ therapy due to safety or efficacy issues. The aim of our study was to evaluate the NTZ discontinuation rate and reasons of discontinuation in a large Italian population of RRMS patients. MATERIALS AND METHODS: The data were extracted from the Italian MS registry in May 2018 and were collected from 51,845 patients in 69 Italian multiple sclerosis centers. MS patients with at least one NTZ infusion in the period between June 1st 2012 to May 15th 2018 were included. Discontinuation rates at each time point were calculated. Reasons for NTZ discontinuation were classified as "lack of efficacy", "progressive multifocal leukoencephalopathy (PML) risk" or "other". RESULTS: Out of 51,845, 5151 patients, 3019 (58.6%) females, with a mean age of 43.6 ± 10.1 years (median 40), were analyzed. Out of 2037 (39.5%) who discontinued NTZ, a significantly higher percentage suspended NTZ because of PML risk compared to lack of efficacy [1682 (32.7% of 5151) vs 221 (4.3%), p < 0.001]; other reasons were identified for 99 (1.9%) patients. Patients discontinuing treatment were older, had longer disease duration and worse EDSS at the time of NTZ initiation and at last follow-up on NTZ treatment. The JCV index and EDSS at baseline were predictors for stopping therapy (HR 2.94, 95% CI 1.22-4.75; p = 0.02; HR 1.36, 95% CI 1.18-5.41; p = 0.04). CONCLUSIONS: Roughly 60% of MS patients stayed on NTZ treatment during the observation period. For those patients in whom NTZ discontinuation was required, it was mainly due to PML concerns.

MR spectroscopy and diffusion imaging in people with human immunodeficiency virus: Relationships to clinical and immunologic findings.

BACKGROUND AND PURPOSE: People with human immunodeficiency virus (HIV; PWH) present a complex array of immunologic and medical disorders that impact brain structure and metabolism, complicating the interpretation of neuroimaging. This pilot study of well-characterized multi-morbid PWH examined how medical and immunologic factors predicted brain characteristics on proton MR spectroscopy (1H-MRS) and diffusion-weighted imaging (DWI). METHODS: Eighteen individuals on combination antiretroviral therapy (cART), with mean age of 56 years, underwent medical history review, neuroimaging, and on the day of imaging, blood draw for assay of 20 plasma cytokines and flow cytometric characterization of peripheral blood mononuclear cell subsets. Predictors of n-acetyl aspartate, choline, myoinositol, glutamate/glutamine, fractional anisotropy and mean diffusivity were identified through bivariate correlation; those significant at p < .1000 were advanced to multivariate analysis, with models created for each neuroimaging outcome. RESULTS: Monocyte subsets and diverse cytokines accounted for 16 of 25 (64%) variables predicting 1H-MRS spectra in frontal gray and white matter and basal ganglia; monocyte subsets did not predict any DWI characteristic. In contrast, age, presence of hypertension, and duration of HIV infection accounted for 13 of 25 (52%) variables predicting diffusion characteristics in the corpus callosum, thalamic radiations, and basal ganglia but only 3 of 25 (12%) predictors of 1H-MRS features. CONCLUSIONS: 1H-MRS neurometabolites were most often predicted by immunologic factors sensitive to temporal variation, whereas DWI metrics were more often related to longer-term disease state. In multi-morbid cART-era populations, selection and interpretation of neuroimaging modalities should account for complex temporal and pathogenetic influences of immunologic abnormality, disease state, and aging.

Menstrual cycle resumption and female fertility after autologous hematopoietic stem cell transplantation for multiple sclerosis.

Data on fertility after autologous hematopoietic stem cell transplantation (aHSCT) in women with multiple sclerosis (MS) are inconclusive. This study aims to report on post-aHSCT menstrual resumption in a multi-center MS-women cohort. Out of 43 women, 30 (70%) recovered menses after a mean time of 6.8 months. Older age (odds ratio (OR) = 0.5, p < 0.0001) and previous pulsed cyclophosphamide (OR = 0.44, p = 0.005) were independently associated with a reduced menstrual recovery probability. Conditioning regimens' intensity resulted not associated with post-procedure amenorrhea. Our results highlight younger age as significantly associated with menses recovery; proper fertility counseling for MS women candidated to aHSCT both prior- and post-transplantation is therefore warranted.

Long-Term Clinical Outcomes of Hematopoietic Stem Cell Transplantation in Multiple Sclerosis.

OBJECTIVE: To determine whether autologous hematopoietic stem cell transplantation (aHSCT) is able to induce durable disease remission in people with multiple sclerosis (MS), we analyzed the long-term outcomes after transplant in a large cohort of MS patients. METHODS: To be included, a minimum data set (consisting of age, MS phenotype, EDSS at baseline, information on transplant technology and at least 1 follow-up visit after transplant) was required. RESULTS: 210 patients were included [relapsing-remitting (RR)MS=122(58%)]. Median baseline EDSS was 6(1-9), mean follow-up was 6.2(±5.0) years. Among RRMS patients, disability worsening-free survival (95%CI) was 85.5%(76.9-94.1%) at 5 years and 71.3%(57.8-84.8%) at 10 years. In patients with progressive MS, disability worsening-free survival was 71.0%(59.4-82.6%) and 57.2%(41.8-72.7%) at 5 and 10 years, respectively. In RRMS patients, EDSS significantly reduced after aHSCT [p=0.001; mean EDSS change per year -0.09 (95%CI=-0.15 to -0.04%)]. In RRMS patients, the use of the BEAM+ATG conditioning protocol was independently associated with a reduced risk of NEDA-3 failure [HR=0.27(0.14-0.50), p<0.001]. Three patients died within 100-days from aHSCT (1.4%); no deaths occurred in patients transplanted after 2007. CONCLUSIONS: aHSCT prevents disability worsening in the majority of patients and induces durable improvement in disability in patients with RRMS. The BEAM+ATG conditioning protocol is associated with a more pronounced suppression of clinical relapses and MRI inflammatory activity. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that for people with MS, aHSCT induces durable disease remission in most patients.

Autologous hematopoietic stem cell transplantation following alemtuzumab therapy in aggressive multiple sclerosis: A report of three cases.

The management of multiple sclerosis patients with persistent disease activity under alemtuzumab treatment is not established yet. Concerns have been raised on the safety of autologous haematopoietic stem cell transplantation (aHSCT) after alemtuzumab treatment because of the risk of serious infectious adverse events. We report short-term safety and efficacy data from three patients treated with aHSCT following alemtuzumab treatment. Early adverse events were consistent with expected transplant toxicities. All patients were free of disease activity at the last follow-up. Our data suggest that aHSCT can be considered as a rescue treatment strategy for MS patients with persistent disease activity during alemtuzumab treatment.

Prevalence of disability improvement as a potential outcome for multiple sclerosis trials.

BACKGROUND: The concept of improvement of disability recently emerged as a new target in multiple sclerosis (MS) studies since the approval of new potent drugs and for testing drugs for neuroprotection and repair. OBJECTIVE: To propose a simple estimator for assessing and comparing the prevalence of improvement over time between groups. METHODS: The prevalence of a transient condition takes into account the incidence and the duration of such condition. We propose here the application of a modified Kaplan-Meier estimator to evaluate and compare between groups the prevalence of improvement over time in a cohort of 121 patients treated with autologous hematopoietic stem cell transplantation. RESULTS: The prevalence of improvement after 5 years from transplant was 50.3% (95%CI: [38.0-63.0]) in relapsing-remitting patients and 6.5% (95%CI: [0-17.8]) in secondary-progressive patients (p < 0.001). Such a difference wouldn't be evident considering the traditional cumulative probability of improvement at 5 years (55.5% in relapsing-remitting vs 33.4% in secondary-progressive patients, p = 0.10). CONCLUSION: This study shows the relevance of a new estimator of prevalence of improvement in MS. This estimator gives simple information on whether a drug can induce a durable improvement in disability and can be considered a potential outcome for trials assessing drugs for neuroprotection or repair.

Molecular imaging of multiple sclerosis: from the clinical demand to novel radiotracers.

BACKGROUND: Brain PET imaging with different tracers is mainly clinically used in the field of neurodegenerative diseases and brain tumors. In recent years, the potential usefulness of PET has also gained attention in the field of MS. In fact, MS is a complex disease and several processes can be selected as a target for PET imaging. The use of PET with several different tracers has been mainly evaluated in the research setting to investigate disease pathophysiology (i.e. phenotypes, monitoring of progression) or to explore its use a surrogate end-point in clinical trials. RESULTS: We have reviewed PET imaging studies in MS in humans and animal models. Tracers have been grouped according to their pathophysiological targets (ie. tracers for myelin kinetic, neuroinflammation, and neurodegeneration). The emerging clinical indication for brain PET imaging in the differential diagnosis of suspected tumefactive demyelinated plaques as well as the clinical potential provided by PET images in view of the recent introduction of PET/MR technology are also addressed. CONCLUSION: While several preclinical and fewer clinical studies have shown results, full-scale clinical development programs are needed to translate molecular imaging technologies into a clinical reality that could ideally fit into current precision medicine perspectives.