CLIPPERS Responsive to Cladribine as a Durable Steroid-Sparing Agent.

OBJECTIVE: We report a case of chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) who achieved durable and steroid-free remission after IV cladribine. METHODS: A 25 year-old man presented with progressively worsening headaches, polydipsia, dysarthria, diplopia and vertigo, and obtundation requiring respiratory support. CSF revealed lymphocytosis, and MRI revealed a perivascular pattern of punctate enhancement involving the pons. An extensive workup for inflammatory, autoimmune, infective, and malignant explanations was unrevealing. He responded dramatically to steroids, compatible with CLIPPERS as a diagnosis of exclusion. Attempts to wean prednisone over the ensuing year resulted in 2 clinical relapses and persistent punctate enhancement. Given significant steroid side effects, steroid-sparing agents were considered. RESULTS: IV cladribine IV (0.0875 mg/kg adjusted body weight daily × 4 days at 0, 4, 8, and 16 months) was selected, given its favorable side effect profile including lower risks of malignancy and infertility and the potential for long-lasting effects. The only side effect was short-term fatigue at the time of infusion. At 20 months after cladribine initiation, he was able to wean-off prednisone altogether. Now at 33 months, he remains in clinical and MRI remission. DISCUSSION: Cladribine is a rational candidate steroid-sparing treatment for presumed neurologic autoimmune conditions such as CLIPPERS. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that cladribine is a steroid-sparing treatment consideration in CLIPPERS.

Mesenchymal stem cell therapy and cognition in MS: Preliminary findings from a phase II clinical trial.

BACKGROUND: Mesenchymal stem cell (MSC) therapies are being evaluated in multiple sclerosis (MS) for possible neural repair. To date, the potential benefits on cognition have received little attention. The objective of the current study was to comprehensively evaluate cognition before and after MSC therapy in those with MS as part of a double-blind, phase II clinical trial. METHODS: Twenty-eight individuals with a confirmed diagnosis of MS were randomly assigned into two study arms. Cognition was evaluated using an expanded Minimal Assessment of Cognitive Function in Multiple Sclerosis (MACFIMS) battery. The battery was administered at Week 0, Week 24, and Week 48 and results were analysed at the group and individual level. RESULTS: No detectable effect of MSC-mediated neural repair was noted in the short-term with respect to cognition, although some cognitive stability or improvement was observed. Decline was noted in some cognitive areas immediately following the procedure at Week 24; though these were temporary with performance returning to baseline levels at Week 48. CONCLUSIONS: While MSC therapy does not lead to improvement in cognition, at least in the short-term, neither does the procedure have lasting deleterious effects. The current findings lend support to the safety and feasibility of MSC therapy as a potentially viable treatment option for individuals with MS.

A real-world single-centre analysis of alemtuzumab and cladribine for multiple sclerosis.

BACKGROUND: Highly active MS may warrant higher efficacy treatments for disease control. However, these often confer more risk and have not been compared in head-to-head clinical trials, making relative efficacy and safety difficult to interpret. Alemtuzumab and cladribine are two high-efficacy treatments given as discrete courses separated by one year, followed by a durable response that potentially does not require ongoing treatment. Before the approval of oral cladribine, our centre had been treating patients with a bioequivalent intravenous (IV) regimen since 2010. The objective of this study is to report the safety and efficacy data of alemtuzumab and cladribine in a real-world, single centre setting. METHODS: We retrospectively reviewed all patients treated with alemtuzumab or cladribine at the Ottawa Hospital MS Clinic with 2 or more years of follow-up. Information on baseline demographic variables, previous treatment, and prior disease activity was collected. Outcomes investigated were "no evidence of disease activity" (NEDA) and its constituents: new clinical relapse, new MRI activity, and Expanded Disability Status Scale (EDSS) progression; as well as any adverse events or treatment discontinuation. We performed univariate and multiple logistic regression to determine differences in 2-year NEDA and time-to-event analyses with Cox regression models to determine factors associated with each outcome through the study period. RESULTS: Forty-six patients were treated with alemtuzumab and 65 with cladribine of whom 51 (78%) received the intravenous regimen, followed for a total of 420.1 person-years. The cladribine group was older (p=.0002), with higher baseline EDSS (p=.0015), and more likely secondary progressive (p<.0001). Alemtuzumab had a higher rate of 2-year NEDA than cladribine (OR 4.78, 95%CI: 1.57-14.50, p=.006), but beyond 2 years the difference was not statistically significant (HR 0.50, 95%CI: 0.25-1. 30, p=.061). More prior treatments were associated with lower likelihood of retaining NEDA (HR 1.26, 95%CI: 1.03-1.54, p=.027). Alemtuzumab had more infusion reactions (80% vs. 17%, p<.0001), shingles (22% vs. 2%, p=.005), and secondary autoimmunity (52% vs. 3%, p<.0001) than cladribine, but there was no difference in grade 3 or higher adverse events (21.7% vs. 18.5%, p=1.0). CONCLUSION: In our cohort alemtuzumab and cladribine achieved similar rates of NEDA in long-term follow-up, with overall less adverse events with cladribine. Patient registries would allow more robust comparisons, detection of adverse events, and assessment of a durable response.

Personalized oncology and BRAFK601N melanoma: model development, drug discovery, and clinical correlation.

PURPOSE: Mutations in BRAF are the most prominent activating mutations in melanoma and are increasingly recognized in other cancers. There is currently no accepted treatment regimen for patients with mutant BRAFK601N melanoma, and the study of melanoma driven by BRAF mutations at the 601 locus is lacking due to a paucity of cellular model systems. Therefore, we sought to better understand the treatment and clinical approach to patients with mutant BRAFK601N melanoma and subsequently develop a novel personalized oncology platform for rare or treatment-refractory cancers. METHODS: We developed and characterized the first patient-derived, naturally occurring BRAFK601N melanoma model, described herein as OHRI-MEL-13, and assessed efficacy using the Prestwick Chemical Library and select targeted therapeutics. RESULTS: OHRI-MEL-13 exhibits loss of heterozygosity of BRAF, closely mimics the original tumor's gene expression profile, is tumorigenic in immune-deficient murine models, and is available for public accession through American Type Culture Collection. We present in silico modeling data, which illustrates the therapeutic failure of BRAFV600E-targeted therapies in BRAFK601N mutants. Our platform elucidated a unique role for MEK inhibition with cobimetinib, which resulted in short-term clinical success by reducing the metastatic burden. CONCLUSION: Our model of BRAFK601N-activated melanoma was developed, thoroughly characterized, and made available for public accession. This model served to demonstrate the feasibility of a novel personalized oncology platform that could be optimized at an institutional level for rare variant or treatment-refractory cancers. We also demonstrate the clinical utility of monotherapy MEK inhibition in a case of BRAFK601N melanoma.

Autologous hematopoietic stem cell transplantation for multiple sclerosis: A current perspective.

The most effective treatment at halting inflammation in patients with highly active multiple sclerosis (MS) is immune ablation followed by autologous hematopoietic stem cell transplantation (AHSCT). Better patient selection and supportive management, as well as advances in conditioning regimens have resulted in improved safety with AHSCT. However, which comorbidities or prior therapies increase the risks associated with AHSCT still need to be determined. In addition, there is still debate as to which AHSCT conditioning regimen offers the best balance of long-term efficacy and safety. New studies comparing AHSCT with highly effective disease-modifying therapies will help to inform on the ideal placement of AHSCT in the treatment algorithm. Currently, many centers are experienced and use AHSCT to treat select patients with MS, contributing to ongoing registries and clinical trials which will help answer these questions.

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.

Does Resetting the Immune System Fix Multiple Sclerosis?

Multiple sclerosis is the leading non-traumatic cause of disability in young adults, affecting up to 100,000 Canadians. This chronic inflammatory and neurodegenerative disease of the central nervous system leads to irreversible neurologic disability if inadequately controlled. Though many current medications are available that reduce inflammatory damage, most patients continue to show some evidence of disease activity and accrue disability. In this review, we discuss the role of immune ablation followed by autologous hematopoietic stem cell transplantation (AHSCT), a therapeutic option for select patients with a more aggressive disease course. By "resetting" the immune system with a variety of ablative conditioning regimens, followed by immune reconstitution, this therapy has shown a durable response in halting evidence of inflammatory activity in most patients, without the need for continued disease-modifying therapies (DMT). Since the introduction of this therapy, there have been advances in patient selection and supportive care, such that morbidity has significantly declined and treatment-related mortality is minimized. Recent phase-II trials have shown excellent results in efficacy and safety of AHSCT; however, challenges exist which require ongoing study. The future challenges include comparing the variety of AHSCT conditioning regimens with each other as well as with existing highly effective DMT; identifying patients with an aggressive disease course through novel biomarkers who may benefit the most from AHSCT; and surveillance of long-term outcomes of different treatment protocols. In select patients, replacing the immune system with AHSCT holds promise of fundamentally altering the trajectory of their aggressive disease course.

Est-ce que le fait de réinitialiser le système immunitaire permet de guérir de la sclérose en plaques? La sclérose en plaques (SP) demeure la principale cause non-traumatique d'invalidité chez les jeunes adultes et affecte jusqu'à 100 000 Canadiens. Cette maladie chronique neuro-dégénérative inflammatoire du système nerveux central entraîne une incapacité neurologique irréversible si elle n'est pas adéquatement contrôlée. Bien que de nombreux traitements médicaux permettent de réduire les dommages inflammatoires de la SP, on continue à observer chez la plupart des patients des signes d'activité de la maladie et une invalidité qui va en croissant. Dans cette étude, nous voulons discuter du rôle de la suppression immunitaire (immune ablation) suivie d'une greffe autologue de moelle osseuse (autologous hematopoietic stem cell transplantation ou AHSCT). Il s'agit ainsi d'une option thérapeutique pour certains patients dont l'évolution de la SP est davantage fulgurante. En « remettant à zéro ¼ le système immunitaire des patients atteints de SP à l'aide de régimes de suppression de la réponse immunitaire, lesquels sont suivis ensuite par une reconstitution immunitaire, cette thérapie a pour effet de stopper l'activité inflammatoire chez la plupart d'entre eux sans qu'ils n'aient eu à entamer des thérapies continues modifiant le cours de la SP. À notre avis, cela constitue une réponse durable. Depuis l'introduction de cette thérapie, on a noté des avancées en ce qui regarde la sélection des patients et les soins prodigués, de sorte que les taux de morbidité ont diminué de façon notable et que la mortalité reliée aux traitements a été minimisée. De récents essais cliniques de phase II ont par ailleurs montré d'excellents résultats en matière d'efficacité et de sécurité. Cela dit, certains défis exigent des études supplémentaires : songeons, par exemple, à une comparaison entre les divers régimes de suppression de la réponse immunitaire et de greffe de moelle osseuse; au fait de comparer ces mêmes régimes à d'autres thérapies modificatrices de la maladie qu'on estime à l'heure actuelle très efficaces; à l'identification, au moyen de biomarqueurs novateurs, de patients dont l'évolution de la SP est davantage accélérée, patients qui pourraient le plus bénéficier d'une greffe de la moelle osseuse ; à la nécessité d'un suivi à long terme des différents protocoles de traitement et de leurs résultats. En somme, le fait de réinitialiser le système immunitaire de certains patients au moyen d'une greffe de moelle osseuse laisse entrevoir la possibilité de pouvoir modifier fondamentalement la trajectoire fulgurante de cette maladie.

Autologous Hematopoietic Cell Transplantation for Treatment-Refractory Relapsing Multiple Sclerosis: Position Statement from the American Society for Blood and Marrow Transplantation.

Multiple sclerosis (MS) is a chronic, disabling, immune-mediated, demyelinating and degenerative disease of the central nervous system. Approved disease-modifying therapies may be incompletely effective in some patients with highly active relapsing disease and high risk of disability. The use of immunoablative or myeloablative therapy followed by autologous hematopoietic cell transplantation (AHCT) has been investigated in retrospective studies, clinical trials, and meta-analyses/systematic reviews as an approach to address this unmet clinical need. On behalf of the American Society for Blood and Bone Marrow Transplantation (ASBMT), a panel of experts in AHCT and MS convened to review available evidence and make recommendations on MS as an indication for AHCT. A review of recent literature identified 8 retrospective studies, 8 clinical trials, and 3 meta-analyses/systematic reviews. In aggregate, these studies indicate that AHCT is an efficacious and safe treatment for active relapsing forms of MS to prevent clinical relapse, magnetic resonance imaging-detectable lesion activity, and worsening disability and to reverse disability without unexpected adverse events. Based on the available evidence, the ASBMT recommends that treatment-refractory relapsing MS with high risk of future disability be considered a "standard of care, clinical evidence available" indication for AHCT. Collaboration of neurologists with expertise in treating MS and transplantation physicians with experience performing AHCT for autoimmune disease is crucial for ensuring appropriate patient selection and optimizing transplantation procedures to improve patient outcomes. Transplantation centers in the United States and Canada are strongly encouraged to report baseline and outcomes data on patients receiving AHCT for multiple sclerosis to the Center for International Blood and Marrow Transplant Research.

Autologous Hematopoietic Stem Cell Transplantation in the Treatment of Multiple Sclerosis.

Multiple sclerosis (MS) is an autoimmune disorder that typically affects young people during their most productive years, causing irreversible damage and accumulation of disability. Treatments over time have had modest effects at completely controlling or suppressing disease activity, but are generally aimed at controlling early dominating inflammation that, over time, accumulates damage and leads to progressive disability. Some unfortunate patients are destined to deteriorate despite even newer and more effective agents because of the inability of these drugs to fully curb the inflammatory component of the disease. These patients require something more that might be capable of halting the disease process. Using high-intensity myeloablative chemotherapeutic agents, it is now possible to completely remove the peripheral immune system and replace it anew from autologous bone marrow-derived hematopoietic stem cells, purged of disease-causing MS cells. This procedure, referred to as hematopoietic stem cell transplantation (HSCT), produces a new immune system that appears tolerant and no longer attacks the central nervous system (CNS).

Autologous hematopoietic stem cell transplantation improves fatigue in multiple sclerosis.

BACKGROUND: Fatigue is a common problem in multiple sclerosis (MS) affecting as many as 90% of patients. The Fatigue Impact Scale (FIS) is a validated measure of fatigue in MS patients. The cause of fatigue in MS is likely multifactorial, with some evidence that ongoing central nervous system (CNS) inflammation is a contributing factor. Immunoablation and autologous hematopoietic stem cell transplantation (aHSCT) have been shown to halt ongoing CNS inflammation. OBJECTIVE: To investigate whether halting all ongoing inflammation with aHSCT impacts FIS scores in patients with severe MS. METHODS: In the Canadian aHSCT study ( ClinicalTrials.gov , NCT01099930), 23 patients underwent aHSCT and had FIS prospectively collected every 6 months for 36 months of follow-up. Change in FIS was analysed by repeated-measures analysis of variance (RMANOVA) with multiple linear regression to determine independent predictors. RESULTS: The median FIS score decreased 36%, from 36 to 23 (p = 0.001), and four patients had 100% reduction. Improvement in FIS correlated with lower age and Expanded Disability Status Scale at baseline, as well as increased independence as evidenced by a return to gainful employment and even driving. CONCLUSION: Patients had significantly less fatigue on average after aHSCT. This may serve to better understand the contribution of ongoing CNS inflammation to fatigue peculiar to MS.

Natural Killer Cells Regulate Th17 Cells After Autologous Hematopoietic Stem Cell Transplantation for Relapsing Remitting Multiple Sclerosis.

In autoimmunity, the balance of different helper T (Th) cell subsets can influence the tissue damage caused by autoreactive T cells. Pro-inflammatory Th1 and Th17 T cells are implicated as mediators of several human autoimmune conditions such as multiple sclerosis (MS). Autologous hematopoietic stem cell transplantation (aHSCT) has been tested in phase 2 clinical trials for MS patients with aggressive disease. Abrogation of new clinical relapses and brain lesions can be seen after ablative aHSCT, accompanied by significant reductions in Th17, but not Th1, cell populations and activity. The cause of this selective decrease in Th17 cell responses following ablative aHSCT is not completely understood. We identified an increase in the kinetics of natural killer (NK) cell reconstitution, relative to CD4+ T cells, in MS patients post-aHSCT, resulting in an increased NK cell:CD4+ T cell ratio that correlated with the degree of decrease in Th17 responses. Ex vivo removal of NK cells from post-aHSCT peripheral blood mononuclear cells resulted in higher Th17 cell responses, indicating that NK cells can regulate Th17 activity. NK cells were also found to be cytotoxic to memory Th17 cells, and this toxicity is mediated through NKG2D-dependent necrosis. Surprisingly, NK cells induced memory T cells to secrete more IL-17A. This was preceded by an early rise in T cell expression of RORC and IL17A mRNA, and could be blocked with neutralizing antibodies against CD58, a costimulatory receptor expressed on NK cells. Thus, NK cells provide initial co-stimulation that supports the induction of a Th17 response, followed by NKG2D-dependent cytotoxicity that limits these cells. Together these data suggest that rapid reconstitution of NK cells following aHSCT contribute to the suppression of the re-emergence of Th17 cells. This highlights the importance of NK cells in shaping the reconstituting immune system following aHSCT in MS patients.

Impact of immunoablation and autologous hematopoietic stem cell transplantation on gray and white matter atrophy in multiple sclerosis.

BACKGROUND: Immunoablation and autologous hematopoietic stem cell transplantation (IA/aHSCT) halts relapses, white matter (WM) lesion formation, and pathological whole-brain (WB) atrophy in multiple sclerosis (MS) patients. Whether the latter was due to effects on gray matter (GM) or WM warranted further exploration. OBJECTIVE: To model GM and WM volume changes after IA/aHSCT to further understand the effects seen on WB atrophy. METHODS: GM and WM volume changes were calculated from serial baseline and follow-up magnetic resonance imaging (MRI) ranging from 1.5 to 10.5 years in 19 MS patients treated with IA/aHSCT. A mixed-effects model with two predictors (total busulfan dose and baseline T1-weighted WM lesion volume "T1LV") characterized the time-courses after IA/aHSCT. RESULTS: Accelerated short-term atrophy of 2.1% and 3.2% occurred in GM and WM, respectively, on average. Both busulfan dose and T1LV were significant predictors of WM atrophy, whereas only busulfan was a significant predictor of GM atrophy. Compared to baseline, a significant reduction in GM atrophy, not WM atrophy, was found. The average rates of long-term GM and WM atrophy were -0.18%/year (standard error (SE): 0.083) and -0.07%/year (SE: 0.14), respectively. CONCLUSION: Chemotherapy-related toxicity affected both GM and WM. WM was further affected by focal T1-weighted lesion-related pathologies. Long-term rates of GM and WM atrophy were comparable to those of normal-aging.

Five Questions Answered: A Review of Autologous Hematopoietic Stem Cell Transplantation for the Treatment of Multiple Sclerosis.

Multiple sclerosis (MS) is thought to be an autoimmune disease targeting the central nervous system leading to demyelination, and axonal and neuronal damage, resulting in progressive disability. More intensive therapies such as immunodepletion with hematopoietic stem-cell rescue are being used at a time prior to patients becoming irreversibly disabled. Over the last 15 years, there has been a shift away from using autologous hematopoietic stem-cell transplants (aHSCT) to treat patients with progressive MS, towards treating those with active inflammation and relapses. There is an increasing body of evidence that aHSCT improves all measured MS outcomes, including burden of disease on MRI, clinical relapses, accumulation of disability, and quality of life of patients with active MS not controlled with standard therapy. Importantly, the progression-free survival curves of these patients plateau after the first few years demonstrating the impact that aHSCT has in changing the natural history of MS, potentially freeing patients from the relentless accumulation of disability. Concurrently there has been a reduction in procedure-related mortality. The results of randomized trials will likely spur further development of this field.

Long-term Outcomes After Autologous Hematopoietic Stem Cell Transplantation for Multiple Sclerosis.

IMPORTANCE: Autologous hematopoietic stem cell transplantation (AHSCT) may be effective in aggressive forms of multiple sclerosis (MS) that fail to respond to standard therapies. OBJECTIVE: To evaluate the long-term outcomes in patients who underwent AHSCT for the treatment of MS in a large multicenter cohort. DESIGN, SETTING, AND PARTICIPANTS: Data were obtained in a multicenter, observational, retrospective cohort study. Eligibility criteria were receipt of AHSCT for the treatment of MS between January 1995 and December 2006 and the availability of a prespecified minimum data set comprising the disease subtype at baseline; the Expanded Disability Status Scale (EDSS) score at baseline; information on the administered conditioning regimen and graft manipulation; and at least 1 follow-up visit or report after transplant. The last patient visit was on July 1, 2012. To avoid bias, all eligible patients were included in the analysis regardless of their duration of follow-up. Data analysis was conducted from September 1, 2014 to April 27, 2015. EXPOSURES: Demographic, disease-related, and treatment-related exposures were considered variables of interest, including age, disease subtype, baseline EDSS score, number of previous disease-modifying treatments, and intensity of the conditioning regimen. MAIN OUTCOMES AND MEASURES: The primary outcomes were MS progression-free survival and overall survival. The probabilities of progression-free survival and overall survival were calculated using Kaplan-Meier survival curves and multivariable Cox proportional hazards regression analysis models. RESULTS: Valid data were obtained from 25 centers in 13 countries for 281 evaluable patients, with median follow-up of 6.6 years (range, 0.2-16 years). Seventy-eight percent (218 of 281) of patients had progressive forms of MS. The median EDSS score before mobilization of peripheral blood stem cells was 6.5 (range, 1.5-9). Eight deaths (2.8%; 95% CI, 1.0%-4.9%) were reported within 100 days of transplant and were considered transplant-related mortality. The 5-year probability of progression-free survival as assessed by the EDSS score was 46% (95% CI, 42%-54%), and overall survival was 93% (95% CI, 89%-96%) at 5 years. Factors associated with neurological progression after transplant were older age (hazard ratio [HR], 1.03; 95% CI, 1.00-1.05), progressive vs relapsing form of MS (HR, 2.33; 95% CI, 1.27-4.28), and more than 2 previous disease-modifying therapies (HR, 1.65; 95% CI, 1.10-2.47). Higher baseline EDSS score was associated with worse overall survival (HR, 2.03; 95% CI, 1.40-2.95). CONCLUSIONS AND RELEVANCE: In this observational study of patients with MS treated with AHSCT, almost half of them remained free from neurological progression for 5 years after transplant. Younger age, relapsing form of MS, fewer prior immunotherapies, and lower baseline EDSS score were factors associated with better outcomes. The results support the rationale for further randomized clinical trials of AHSCT for the treatment of MS.

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.

Immunoablation and autologous haemopoietic stem-cell transplantation for aggressive multiple sclerosis: a multicentre single-group phase 2 trial.

BACKGROUND: Strong immunosuppression, including chemotherapy and immune-depleting antibodies followed by autologous haemopoietic stem-cell transplantation (aHSCT), has been used to treat patients with multiple sclerosis, improving control of relapsing disease. We addressed whether near-complete immunoablation followed by immune cell depleted aHSCT would result in long-term control of multiple sclerosis. METHODS: We did this phase 2 single-arm trial at three hospitals in Canada. We enrolled patients with multiple sclerosis, aged 18-50 years with poor prognosis, ongoing disease activity, and an Expanded Disability Status Scale of 3.0-6.0. Autologous CD34 selected haemopoietic stem-cell grafts were collected after mobilisation with cyclophosphamide and filgrastim. Immunoablation with busulfan, cyclophosphamide, and rabbit anti-thymocyte globulin was followed by aHSCT. The primary outcome was multiple sclerosis activity-free survival (events were clinical relapse, appearance of a new or Gd-enhancing lesion on MRI, and sustained progression of Expanded Disability Status Scale score). This study was registered at ClinicalTrials.gov, NCT01099930. FINDINGS: Between diagnosis and aHSCT, 24 patients had 167 clinical relapses over 140 patient-years with 188 Gd-enhancing lesions on 48 pre-aHSCT MRI scans. Median follow-up was 6.7 years (range 3.9-12.7). The primary outcome, multiple sclerosis activity-free survival at 3 years after transplantation was 69.6% (95% CI 46.6-84.2). With up to 13 years of follow-up after aHSCT, no relapses occurred and no Gd enhancing lesions or new T2 lesions were seen on 314 MRI sequential scans. The rate of brain atrophy decreased to that expected for healthy controls. One of 24 patients died of transplantation-related complications. 35% of patients had a sustained improvement in their Expanded Disability Status Scale score. INTERPRETATION: We describe the first treatment to fully halt all detectable CNS inflammatory activity in patients with multiple sclerosis for a prolonged period in the absence of any ongoing disease-modifying drugs. Furthermore, many of the patients had substantial recovery of neurological function despite their disease's aggressive nature. FUNDING: Multiple Sclerosis Scientific Research Foundation.

Reciprocal cellular cross-talk within the tumor microenvironment promotes oncolytic virus activity.

Tumors are complex ecosystems composed of networks of interacting 'normal' and malignant cells. It is well recognized that cytokine-mediated cross-talk between normal stromal cells, including cancer-associated fibroblasts (CAFs), vascular endothelial cells, immune cells, and cancer cells, influences all aspects of tumor biology. Here we demonstrate that the cross-talk between CAFs and cancer cells leads to enhanced growth of oncolytic virus (OV)-based therapeutics. Transforming growth factor-ß (TGF-ß) produced by tumor cells reprogrammed CAFs, dampened their steady-state level of antiviral transcripts and rendered them sensitive to virus infection. In turn, CAFs produced high levels of fibroblast growth factor 2 (FGF2), initiating a signaling cascade in cancer cells that reduced retinoic acid-inducible gene I (RIG-I) expression and impeded the ability of malignant cells to detect and respond to virus. In xenografts derived from individuals with pancreatic cancer, the expression of FGF2 correlated with the susceptibility of the cancer cells to OV infection, and local application of FGF2 to resistant tumor samples sensitized them to virotherapy both in vitro and in vivo. An OV engineered to express FGF2 was safe in tumor-bearing mice, showed improved therapeutic efficacy compared to parental virus and merits consideration for clinical testing.