BackgroundAutologous haematopoietic stem cell transplantation (AHSCT) has been explored as a therapeutic intervention in multiple sclerosis (MS) over the last two decades; however, prospective clinical trials of the most common myeloablative conditioning regimen, BEAM, are limited. Furthermore, patient selection, optimal chemotherapeutic regimen and immunological changes associated with disease response require ongoing exploration. We present the outcomes, safety and immune reconstitution (IR) of patients with active, treatment refractory MS.MethodsThis study was a single-centre, phase II clinical trial of AHSCT for patients with active relapsing remitting (RRMS) and secondary progressive MS (SPMS). Patients underwent AHSCT using BEAM (carmustine, etoposide, cytarabine, melphalan)+antithymocyte globulin chemotherapeutic regimen.OutcomesThe primary outcome was event-free survival (EFS); defined as no clinical or radiological relapses and no disability progression. Multiparameter flow cytometry was performed for evaluation of post-transplant IR in both MS and lymphoma patients receiving the same chemotherapy regimen.ResultsThirty-five patients (20 RRMS, 15 SPMS) completed AHSCT, with a median follow-up of 36 months (range 12–66). The median Expanded Disability Status Scores (EDSS) was 6 (2–7) and patients had failed a median of 4 (2–7) disease modifying therapies. 66% failed treatment with natalizumab. EFS at 3 years was 60%, (70% RRMS). Sustained improvement in EDSS was seen in 15 (44%) of patients. There was no treatment-related mortality. A sustained rise in CD39+ T regulatory cells, immunosuppressive CD56hi natural killer cells and ablation of proinflammatory mucosal-associated invariant T cells was seen for 12 months following AHSCT in patients with MS. These changes did not occur in patients with lymphoma receiving the same chemotherapy for AHSCT.ConclusionsThe EFS in our MS cohort is significantly greater than other high-efficacy immunosuppressive therapies and similar to other AHSCT studies despite a more heavily pretreated cohort.Trial registration numberACTRN12613000339752.

BackgroundTrials of fluoxetine for recovery after stroke report conflicting results. The Assessment oF FluoxetINe In sTroke recoverY (AFFINITY) trial aimed to determine if daily fluoxetine for 6 months after stroke improves functional outcome in Australasian and Vietnamese patients. MethodsAFFINITY was a randomised, parallel-group, double-blind, placebo-controlled trial conducted in 43 hospital stroke units in Australia (n=29), New Zealand (4), and Vietnam (10). Eligible patients were adults with a clinical diagnosis of stroke in the previous 2-15 days and a persisting neurological deficit. Patients were randomised via a web-based system using a minimisation algorithm to once daily, oral fluoxetine 20mg or matching placebo for 6 months. Patients, investigators and outcome assessors were masked to the treatment allocation. The primary outcome was functional outcome, measured by the modified Rankin scale (mRS), at 6 months. The primary analysis was an ordinal logistic regression of the mRS at 6 months, adjusted for minimisation variables. Analyses were according to the patient's treatment allocation. The trial is registered with the ACTRN registry, number 12611000774921. FindingsPowered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation 1280 patients were recruited in Australia (n=532), New Zealand (n=42) and Vietnam (n=706) between 11 January 2013 and 30 June 2019; 642 were allocated fluoxetine and 638 placebo. Adherence to trial medication (mean 167 [SD 48] days) was similar between groups. At 6 months, mRS data were available in 624 (97.2%) patients allocated fluoxetine and 632 (99.1%) placebo. The distribution of mRS categories at 6 months was similar in the fluoxetine and placebo groups (adjusted common odds ratio 0.936, 95% CI 0.762-1.150; p=0.53), and consistent among all pre-defined subgroups. Compared to placebo, patients allocated fluoxetine had more falls (20 [3.12%] vs 7 [1.10%]; p=0.02), bone fractures (19 [2•96%] vs 6 [0.94%]; p=0.01) and epileptic seizures (10 [1.56%] vs 2 [0.31%]; p=0.04) at 6 months. InterpretationFluoxetine 20mg daily for 6 months after acute stroke did not improve functional outcome and increased the risk of falls, bone fractures, and seizures. These results do not support the use of fluoxetine to improve outcome after stroke.

Multiple sclerosis (MS) is an inflammatory disorder of the central nervous system where evidence implicates an aberrant adaptive immune response in the accrual of neurological disability. The inflammatory phase of the disease responds to immunomodulation to varying degrees of efficacy; however, no therapy has been proven to arrest progression of disability. Recently, more intensive therapies, including immunoablation with autologous hematopoietic stem cell transplantation (AHSCT), have been offered as a treatment option to retard inflammatory disease, prior to patients becoming irreversibly disabled. Empirical clinical observations support the notion that the immune reconstitution (IR) that occurs following AHSCT is associated with a sustained therapeutic benefit; however, neither the pathogenesis of MS nor the mechanism by which AHSCT results in a therapeutic benefit has been clearly delineated. Although the antigenic target of the aberrant immune response in MS is not defined, accumulated data suggest that IR following AHSCT results in an immunotolerant state through deletion of pathogenic clones by a combination of direct ablation and induction of a lymphopenic state driving replicative senescence and clonal attrition. Restoration of immunoregulation is evidenced by changes in regulatory T cell populations following AHSCT and normalization of genetic signatures of immune homeostasis. Furthermore, some evidence exists that AHSCT may induce a rebooting of thymic function and regeneration of a diversified naïve T cell repertoire equipped to appropriately modulate the immune system in response to future antigenic challenge. In this review, we discuss the immunological mechanisms of IR therapies, focusing on AHSCT, as a means of recalibrating the dysfunctional immune response observed in MS.