Potential neuroprotective effect of Fingolimod in multiple sclerosis and its association with clinical variables

Ocrelizumab reduces cortical and deep grey matter loss compared to the S1P-receptor modulator in multiple sclerosis

INTRODUCTION

Ocrelizumab (OCR) and Fingolimod (FGL) are two high-efficacy treatments in multiple sclerosis which, besides their strong anti-inflammatory activity, may limit neurodegeneration.

AIM

To compare the effect of OCR and FGL on clinical and MRI endpoints.

METHODS

95 relapsing-remitting patients (57 OCR, 38 FGL) clinically followed for 36 months underwent a 3-Tesla MRI at baseline and after 24 months. The annualized relapse rate, EDSS, new cortical/white matter lesions and regional cortical and deep grey matter volume loss were evaluated.

RESULTS

OCR reduced the relapse rate from 0.48 to 0.04, FGL from 0.32 to 0.05 (both p < 0.001). Compared to FGL, OCR-group experienced fewer new white matter lesions (12% vs 32%, p = 0.005), no differences in new cortical lesions, lower deep grey matter volume loss (- 0.12% vs - 0.66%; p = 0.002, Cohen's d = 0.54), lower global cortical thickness change (- 0.45% vs - 0.70%; p = 0.036; d = 0.42) and reduced cortical thinning/volume loss in several regions of interests, including those of parietal gyrus (d-range = 0.65-0.71), frontal gyrus (d-range = 0.47-0.60), cingulate (d-range = 0.41-0.72), insula (d = 0.36), cerebellum (cortex d = 0.72, white matter d = 0.44), putamen (d = 0.35) and thalamus (d = 0.31). The effect on some regional thickness changes was confirmed in patients without focal lesions.

CONCLUSIONS

When compared with FGL, patients receiving OCR showed greater suppression of focal MRI lesions accumulation and lower cortical and deep grey matter volume loss.

Immune System and Brain/Intestinal Barrier Functions in Psychiatric Diseases: Is Sphingosine-1-Phosphate at the Helm?

Over the past few decades, extensive research has shed light on immune alterations and the significance of dysfunctional biological barriers in psychiatric disorders. The leaky gut phenomenon, intimately linked to the integrity of both brain and intestinal barriers, may play a crucial role in the origin of peripheral and central inflammation in these pathologies. Sphingosine-1-phosphate (S1P) is a bioactive lipid that regulates both the immune response and the permeability of biological barriers. Notably, S1P-based drugs, such as fingolimod and ozanimod, have received approval for treating multiple sclerosis, an autoimmune disease of the central nervous system (CNS), and ulcerative colitis, an inflammatory condition of the colon, respectively. Although the precise mechanisms of action are still under investigation, the effectiveness of S1P-based drugs in treating these pathologies sparks a debate on extending their use in psychiatry. This comprehensive review aims to delve into the molecular mechanisms through which S1P modulates the immune system and brain/intestinal barrier functions. Furthermore, it will specifically focus on psychiatric diseases, with the primary objective of uncovering the potential of innovative therapies based on S1P signaling.

Functions of Astrocytes under Normal Conditions and after a Brain Disease

In the central nervous system (CNS) there are a greater number of glial cells than neurons (between five and ten times more). Furthermore, they have a greater number of functions (more than eight functions). Glia comprises different types of cells, those of neural origin (astrocytes, radial glia, and oligodendroglia) and differentiated blood monocytes (microglia). During ontogeny, neurons develop earlier (at fetal day 15 in the rat) and astrocytes develop later (at fetal day 21 in the rat), which could indicate their important and crucial role in the CNS. Analysis of the phylogeny reveals that reptiles have a lower number of astrocytes compared to neurons and in humans this is reversed, as there have a greater number of astrocytes compared to neurons. These data perhaps imply that astrocytes are important and special cells, involved in many vital functions, including memory, and learning processes. In addition, astrocytes are involved in different mechanisms that protect the CNS through the production of antioxidant and anti-inflammatory proteins and they clean the extracellular environment and help neurons to communicate correctly with each other. The production of inflammatory mediators is important to prevent changes in brain homeostasis. On the contrary, excessive, or continued production appears as a characteristic element in many diseases, such as Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS), and in neurodevelopmental diseases, such as bipolar disorder, schizophrenia, and autism. Furthermore, different drugs and techniques have been developed to reverse oxidative stress and/or excess of inflammation that occurs in many CNS diseases, but much remains to be investigated. This review attempts to highlight the functional relevance of astrocytes in normal and neuropathological conditions by showing the molecular and cellular mechanisms of their role in the CNS.

S1PR1 modulators in multiple sclerosis: Efficacy, safety, comparison, and chemical structure insights

Multiple sclerosis (MS) is a neurological disease that leads to severe physical and cognitive disabilities. Drugs used in the treatment of MS vary from small synthetic molecules to large macromolecules such as antibodies. Sphingosine 1-phosphate receptor modulators are frequently used for the treatment of MS. These medicines prevent the egress of lymphocytes from secondary lymphoid organs leading to immune system suppression. Currently, four S1PR modulators are on the market and several potential drug candidates are in clinical trials for the treatment of MS. These compounds differ in chemical structure, adverse effects, and efficacy points of view. The current article reviews the latest studies on S1PR1 modulators and compares them with other MS drugs in terms of efficacy, tolerability, and safety. A special focus was dedicated to discussing the structure-activity relationships of these compounds and performing a three-dimensional quantitative structure-activity relationship (3D-QSAR) analysis to gain better insight into the ligand-receptor interaction mode.

Fingolimod effects on the brain are mediated through biochemical modulation of bioenergetics, autophagy, and neuroinflammatory networks

Fingolimod (FTY720) is an oral drug approved by the Food and Drug Administration (FDA) for management of multiple sclerosis (MS) symptoms, which has also shown beneficial effects against Alzheimer's (AD) and Parkinson's (PD) diseases pathologies. Although an extensive effort has been made to identify mechanisms underpinning its therapeutic effects, much remains unknown. Here, we investigated Fingolimod induced proteome changes in the cerebellum (CB) and frontal cortex (FC) regions of the brain which are known to be severely affected in MS, using a tandem mass tag (TMT) isobaric labeling-based quantitative mass-spectrometric approach to investigate the mechanism of action of Fingolimod. This study identified 6749 and 6319 proteins in CB and FC, respectively, and returned 2609 and 3086 differentially expressed proteins in mouse CB and FC, respectively, between Fingolimod treated and control groups. Subsequent bioinformatics analyses indicated a metabolic reprogramming in both brain regions of the Fingolimod treated group, where oxidative phosphorylation was upregulated while glycolysis and pentose phosphate pathway were downregulated. In addition, modulation of neuroinflammation in the Fingolimod treated group was indicated by upregulation of retrograde endocannabinoid signaling and autophagy pathways, and downregulation of neuroinflammation related pathways including neutrophil degranulation and the IL-12 mediated signaling pathway. Our findings suggest that Fingolimod may exert its protective effects on the brain by inducing metabolic reprogramming and neuroinflammation pathway modulation.

Sphingolipid metabolism governs Purkinje cell patterned degeneration in Atxn1[82Q]/+ mice

Neuronal subtypes are differentially affected by neuropathologies. For example, Purkinje cells, the principal neurons of the cerebellum, can be divided in subpopulations based on their sensitivity to pathological insult. However, the molecular mechanisms explaining why, among seemingly identical neurons, some will degenerate while others survive remain unknown. Here, we analyzed, in a disease model of cerebellar neurodegeneration, the metabolism of sphingolipids, complex lipids involved in cell apoptosis, and found that specific sphingolipids accumulate in the cerebellar region primarily affected by neurodegeneration. Preventing this accumulation by disrupting sphingolipid metabolism via genetic mutation caused a neuroprotective effect on subpopulations of Purkinje cells. Thus, our data indicate that sphingolipid metabolism is involved in the predisposition of neuronal subtypes to neurodegeneration.

Patterned degeneration of Purkinje cells (PCs) can be observed in a wide range of neuropathologies, but mechanisms behind nonrandom cerebellar neurodegeneration remain unclear. Sphingolipid metabolism dyshomeostasis typically leads to PC neurodegeneration; hence, we questioned whether local sphingolipid balance underlies regional sensitivity to pathological insults. Here, we investigated the regional compartmentalization of sphingolipids and their related enzymes in the cerebellar cortex in healthy and pathological conditions. Analysis in wild-type animals revealed higher sphingosine kinase 1 (Sphk1) levels in the flocculonodular cerebellum, while sphingosine-1-phosphate (S1P) levels were higher in the anterior cerebellum. Next, we investigated a model for spinocerebellar ataxia type 1 (SCA1) driven by the transgenic expression of the expanded Ataxin 1 protein with 82 glutamine (82Q), exhibiting severe PC degeneration in the anterior cerebellum while the flocculonodular region is preserved. In Atxn1[82Q]/+ mice, we found that levels of Sphk1 and Sphk2 were region-specific decreased and S1P levels increased, particularly in the anterior cerebellum. To determine if there is a causal link between sphingolipid levels and neurodegeneration, we deleted the Sphk1 gene in Atxn1[82Q]/+ mice. Analysis of Atxn1[82Q]/+; Sphk1^−/− mice confirmed a neuroprotective effect, rescuing a subset of PCs in the anterior cerebellum, in domains reminiscent of the modules defined by AldolaseC expression. Finally, we showed that Sphk1 deletion acts on the ATXN1[82Q] protein expression and prevents PC degeneration. Taken together, our results demonstrate that there are regional differences in sphingolipid metabolism and that this metabolism is directly involved in PC degeneration in Atxn1[82Q]/+ mice.

Transcriptomic Analysis of Peripheral Monocytes upon Fingolimod Treatment in Relapsing Remitting Multiple Sclerosis Patients

Fingolimod (FTY), a second-line oral drug approved for relapsing remitting Multiple Sclerosis (RRMS) acts in preventing lymphocyte migration outside lymph nodes; moreover, several lines of evidence suggest that it also inhibits myeloid cell activation. In this study, we investigated the transcriptional changes induced by FTY in monocytes in order to better elucidate its mechanism of action. CD14⁺ monocytes were collected from 24 RRMS patients sampled at baseline and after 6 months of treatment and RNA profiles were obtained through next-generation sequencing. We conducted pathway and sub-paths analysis, followed by centrality analysis of cell-specific interactomes on differentially expressed genes (DEGs). We investigated also the predictive role of baseline monocyte transcription profile in influencing the response to FTY therapy. We observed a marked down-regulation effect (60 down-regulated vs. 0 up-regulated genes). Most of the down-regulated DEGs resulted related with monocyte activation and migration like IL7R, CCR7 and the Wnt signaling mediators LEF1 and TCF7. The involvement of Wnt signaling was also confirmed by subpaths analyses. Furthermore, pathway and network analyses showed an involvement of processes related to immune function and cell migration. Baseline transcriptional profile of the HLA class II gene HLA-DQA1 and HLA-DPA1 were associated with evidence of disease activity after 2 years of treatment. Our data support the evidence that FTY induces major transcriptional changes in monocytes, mainly regarding genes involved in cell trafficking and immune cell activation. The baseline transcriptional levels of genes associated with antigen presenting function were associated with disease activity after 2 years of FTY treatment.

Neuroprotective role of sphingolipid rheostat in excitotoxic retinal ganglion cell death

The glutamate excitotoxicity has been suggested as a factor involved in the loss of retinal neuronal cells, including retinal ganglion cell (RGC), in various retinal degenerative diseases including ischemia-reperfusion injury, diabetic retinopathy, and glaucoma. Excitotoxic RGC death is caused not only by direct damage to RGCs but also by indirect damage due to the inflammation of retinal glial cells. Sphingosine 1-phosphate (S1P) and ceramides are bioactive sphingolipids which have been shown to possess important physiological roles in cellular survival and apoptosis, and the balance between S1P and ceramide, sphingolipid rheostat, has been suggested to be important for determining cellular fate. Therefore, we conducted the present study to clarify the neuroprotective role of sphingolipid rheostat in excitotoxic RGC death in vivo and in vitro. Acute RGC death was induced by intravitreal N-methyl-d-aspartate (NMDA) injection in the mouse. The mRNA expression of sphingosine kinase (SphK1/SphK2) was examined by quantitative real-time polymerase chain reaction (qRT-PCR). The expressions of SphK1/2, S1P, S1P-receptor (S1PR), glial fibrillary acidic protein (GFAP), Iba1, and CD31 were examined by immunostaining. Retinal sphingolipids and ceramides were quantified by liquid chromatography with tandem mass spectrometry. The neuroprotective effect of the sphingosine kinase inhibitor (SKI) on RGC death was assessed by RGC count and Terminal deoxynucleotidyl transferase dUTP nick-end labeling assay. Further, the in vitro effect of SKI was investigated using rat primary cultured RGCs and glial cells. In addition, MG5 cells and A1 cells, which were mouse microglia and astrocyte cell-line, were also used. The expression of cleaved-caspase-3, GFAP, and Iba1 in RGCs, primary glial cells, MG5 cells, and A1 cells was assessed by immunostaining. NMDA injection resulted in mRNA upregulation of SphK1; however, SphK2 was reduced in the mouse retina. SphKs, S1P, S1PR1, S1PR2, and GFAP expression increased in the early-stage NMDA group, whereas S1P and GFAP were higher in the late-stage NMDA + SKI group. In the NMDA group, S1P expression was lower whereas sphingosine, C20, C22, and C24 ceramides showed higher levels. The proportion of very-long-chain ceramide was elevated in the NMDA group but reduced in the NMDA + SKI group. SKI treatment significantly increased RGC survival in retinal wholemount analysis and decreased apoptosis in the ganglion cell layer and inner nuclear layer. In vitro, SKI suppressed excitotoxic RGC death, cleaved-caspase-3 expression, and activated glial cells. The findings in the present study provide the first evidence demonstrating the involvement of sphingolipid rheostat in the neuroprotection against excitotoxic RGC death. Therefore, regulation of sphingolipid rheostat might serve as a potential therapy for retinal degenerative disease.

Disability progression in relapse-free multiple sclerosis patients on fingolimod versus interferon-beta/glatiramer acetate

BACKGROUND

Disability progression independent of relapses (PIRA) has been described as a frequent phenomenon in relapsing-remitting multiple sclerosis (RRMS).

OBJECTIVE

To compare the occurrence of disability progression in relapse-free RRMS patients on interferon-beta/glatiramer acetate (IFN/GA) versus fingolimod.

METHODS

This study is based on data from the Swiss association for joint tasks of health insurers. Time to relapse and 12-month confirmed disability progression were compared between treatment groups using multivariable Cox regression analysis with confounder adjustment. Inverse-probability weighting was applied to correct for the bias that patients on fingolimod have a higher chance to remain relapse-free than patients on IFN/GA.

RESULTS

We included 1640 patients (64% IFN/GA, 36% fingolimod, median total follow-up time = 4-5 years). Disease-modifying treatment (DMT) groups were well balanced with regard to potential confounders. Disability progression was observed in 155 patients (8.8%) on IFN/GA and 51 (7.6%) on fingolimod, of which 44 and 23 were relapse-free during the initial DMT, respectively. Adjusted standard regression analysis on all patients indicated that those on fingolimod experience less frequently disability progression compared with IFN/GA (hazard ratio = 0.53 (95% confidence interval = 0.37-0.76)). After bias correction, this was also true for patients without relapses (hazard ratio=0.56 (95% confidence interval = 0.32-0.98).

CONCLUSION

Our analysis indicates that fingolimod is superior to IFN/GA in preventing disability progression in both relapsing and relapse-free, young, newly diagnosed RRMS patients.

Fingolimod after a first unilateral episode of acute optic neuritis (MOVING) - preliminary results from a randomized, rater-blind, active-controlled, phase 2 trial

Background

Neuroprotection and promotion of remyelination represent important therapeutic gaps in multiple sclerosis (MS). Acute optic neuritis (ON) is a frequent MS manifestation. Based on the presence and properties of sphingosine-1-phosphate receptors (S1PR) on astrocytes and oligodendrocytes, we hypothesized that remyelination can be enhanced by treatment with fingolimod, a S1PR modulator currently licensed for relapsing-remitting MS.

Methods

MOVING was an investigator-driven, rater-blind, randomized clinical trial. Patients with acute unilateral ON, occurring as a clinically isolated syndrome or MS relapse, were randomized to 6 months of treatment with 0.5 mg oral fingolimod or subcutaneous IFN-β 1b 250 μg every other day. The change in multifocal visual evoked potential (mfVEP) latency of the qualifying eye was examined as the primary (month 6 vs. baseline) and secondary (months 3, 6 and 12 vs. baseline) outcome. In addition, full field visual evoked potentials, visual acuity, optical coherence tomography as well as clinical relapses and measures of disability, cerebral MRI, and self-reported visual quality of life were obtained for follow-up. The study was halted due to insufficient recruitment (n = 15), and available results are reported.

Results

Per protocol analysis of the primary endpoint revealed a significantly larger reduction of mfVEP latency at 6 months compared to baseline with fingolimod treatment (n = 5; median decrease, 15.7 ms) than with IFN-β 1b treatment (n = 4; median increase, 8.15 ms) (p <  0.001 for interaction). Statistical significance was maintained in the secondary endpoint analysis. Descriptive results are reported for other endpoints.

Conclusion

Preliminary results of the MOVING trial argue in support of a beneficial effect of fingolimod on optic nerve remyelination when compared to IFN-β treatment. Interpretation is limited by the small number of complete observations, an unexpected deterioration of the control group and a difference in baseline mfVEP latencies. The findings need to be confirmed in larger studies.

Trial registration

The trial was registered as EUDRA-CT 2011–004787-30 on October 26, 2012 and as NCT01647880 on July 24, 2012.

Fingolimod Augments Monomethylfumarate Killing of GBM Cells

Previously we demonstrated that the multiple sclerosis drug dimethyl fumarate (DMF) and its plasma breakdown product MMF could interact with chemotherapeutic agents to kill both GBM cells and activated microglia. The trial NCT02337426 demonstrated the safety of DMF in newly diagnosed GBM patients when combined with the standard of care Stupp protocol. We hypothesized that another multiple sclerosis drug, fingolimod (FTY720) would synergize with MMF to kill GBM cells. MMF and fingolimod interacted in a greater than additive fashion to kill PDX GBM isolates. MMF and fingolimod radiosensitized glioma cells and enhanced the lethality of temozolomide. Exposure to [MMF + fingolimod] activated an ATM-dependent toxic autophagy pathway, enhanced protective endoplasmic reticulum stress signaling, and inactivated protective PI3K, STAT, and YAP function. The drug combination reduced the expression of protective c-FLIP-s, MCL-1, BCL-XL, and in parallel caused cell-surface clustering of the death receptor CD95. Knock down of CD95 or over-expression of c-FLIP-s or BCL-XL suppressed killing. Fingolimod and MMF interacted in a greater than additive fashion to rapidly enhance reactive oxygen species production and over-expression of either thioredoxin or super-oxide dismutase two significantly reduced the drug-induced phosphorylation of ATM, autophagosome formation and [MMF + fingolimod] lethality. In contrast, the production of ROS was only marginally reduced in cells lacking ATM, CD95, or Beclin1. Collectively, our data demonstrate that the primary generation of ROS by [MMF + fingolimod] plays a key role, via the induction of toxic autophagy and death receptor signaling, in the killing of GBM cells.

Improving Outcomes in Pediatric Multiple Sclerosis: Current and Emerging Treatments

Pediatric-onset multiple sclerosis (MS) comprises 2-5% of MS cases, and is known to be associated with high disease activity and the accumulation of disability at an earlier age than their adult-onset counterparts. Appropriate therapy leading to disease control has the potential to alter the known trajectory of adverse long-term physical, cognitive, and psychosocial outcomes in this population. Thus, optimizing treatment for children and adolescents with MS is of paramount importance. The last decade has seen a growing number of disease-modifying therapies approved for relapsing MS in adults, and available agents now include oral, injectable, and infusion therapies. Recently, the development of randomized controlled MS trials in youth has led to the first agent approved by the US FDA for the treatment of pediatric MS-fingolimod. With this, we have entered a new era of knowledge and treatment in this population and ongoing pediatric trials are expected to further inform clinical management. With the emergence of highly effective therapies targeting the inflammatory component of the disease, there has been increased interest in identifying treatment strategies that instead target mechanisms such as remyelination/repair, neuroprotection, or rehabilitation. The potential role for such emerging therapies in the treatment of pediatric MS remains an important area of study. In this review, we discuss current evidence for MS therapies in children including the treatment of acute relapses, disease-modifying therapies, and symptomatic management. We will also discuss evidence for emerging therapies, including remyelinating and neuroprotective agents.

Identifying risk factors for cognitive issues in multiple sclerosis

INTRODUCTION

Cognitive impairment (CI) in Multiple Sclerosis (MS) has progressively regained clinical and research interest and is currently recognized as a debilitating and burdensome problem for these patients. Studying risk and protecting factors that may influence the development and course of CI is currently an area of increasing interest, due to the potential for preventive strategies. Areas covered: In this narrative review the authors briefly addressed the physiopathologic basis, assessment and management of CI in MS and then focused on identifying modifiable and not modifiable risk factors for CI in MS, providing an overview of the current knowledge in the field and indicating avenues for future research. Expert opinion: Improving our understanding of potentially modifiable environmental and lifestyle risk factors or protective factors for CI is important in order to prompt preventive strategies and orient patient counselling and clinical management. To this aim, we need to enhance the current level of evidence linking lifestyle factors to cognition and evaluate some factors that were only preliminary addressed in research. Moreover, we need to explore the role of each factor into the subject cognitive outcome, next to the possible interactions between different environmental factors as well as between environmental and genetic factors.

Local delivery of FTY720 and NSCs on electrospun PLGA scaffolds improves functional recovery after spinal cord injury

Spinal cord injury (SCI) is a common issue in the clinic that causes severe motor and sensory dysfunction below the lesion level. FTY720, also known as fingolimod, has recently been reported to exert a positive effect on the recovery from a spinal cord injury. Through local delivery to the lesion site, FTY720 effectively integrates with biomaterials, and the systemic adverse effects are alleviated. However, the effects of the proper mass ratio of FTY720 in biomaterials on neural stem cell (NSC) proliferation and differentiation, as well as functional recovery after SCI, have not been thoroughly investigated. In our study, we fabricated electrospun poly (lactide-co-glycolide) (PLGA)/FTY720 scaffolds at different mass ratios (0.1%, 1%, and 10%) and characterized these scaffolds. The effects of electrospun PLGA/FTY720 scaffolds on NSC proliferation and differentiation were measured. Then, a rat model of spinal transection was established to investigate the effects of PLGA/FTY720 scaffolds loaded with NSCs. Notably, 1% PLGA/FTY720 scaffolds exerted the best effects on the proliferation and differentiation of NSCs and 10% PLGA/FTY720 was cytotoxic to NSCs. Based on the Basso, Beattie, and Bresnahan (BBB) score, HE staining and immunofluorescence staining, the PLGA/FTY720 scaffold loaded with NSCs effectively promoted the recovery of spinal cord function. Thus, FTY720 properly integrated with electrospun PLGA scaffolds, and electrospun PLGA/FTY720 scaffolds loaded with NSCs may have potential applications for SCI as a nerve implant.

Spinal cord injury (SCI) is a common issue in the clinic that causes severe motor and sensory dysfunction below the lesion level.

The effect of fingolimod on focal and diffuse grey matter damage in active MS patients

INTRODUCTION

The mechanism of action of fingolimod within the central nervous system and its efficacy in reducing/preventing both focal and diffuse grey matter (GM) damage in active multiple sclerosis (MS) are not completely understood.

METHODS

In this longitudinal, 2-year prospective, phase IV, single-blind study, 40 MS patients treated with fingolimod and 39 untreated age, gender, and disability-matched MS patients were enrolled. Each patient underwent a neurological examination every 6 months and a 3T MRI at the beginning of the treatment and after 24 months. The accumulation of new cortical lesions (CLs) and the progression of regional GM atrophy were compared between the two groups.

RESULTS

At the end of the study (T24), the percentage of patients with new CLs (13.5 vs. 89%, p < 0.001) and the percentage of GM volume change was lower in the treated group (p < 0.001). The regional analysis revealed that the treated group had also less volume loss in thalamus, caudatus, globus pallidus, cingulate cortex, and hippocampus (p < 0.001), as well as in, cerebellum, superior frontal gyrus, and insular-long gyrus (p < 0.05). Patients with no evidence of disease activity were 60% in the treated group and 10% in the untreated group (p < 0.001).

CONCLUSIONS

These results suggest a possible protective effect of fingolimod on focal and diffuse GM damage.

Sequencing of high-efficacy disease-modifying therapies in multiple sclerosis: perspectives and approaches

Multiple sclerosis (MS) is characterized by chronic inflammation in conjunction with neurodegeneration within the central nervous system. Most individuals with MS begin with a relapsing remitting course that later transitions to secondary progressive MS. Currently available disease-modifying therapies (DMTs) for relapsing MS have been demonstrated to reduce disease activity, however most patients require a change in therapy over the course of their disease. Treatment goals include the prevention of relapses and disability accumulation and to achieve this objective requires careful planning. Sequencing of DMTs for individual patients should be designed in such a way to maximize disease control and minimize risk based on the mechanism of action, pharmacokinetic and pharmacodynamic properties of each therapy. This includes the DMT patients are being switched from to those they are being switched to. The reversibility of immune system effects should be a key consideration for DMT sequence selection. This feature varies across DMTs and should factor more prominently in decision making as newer treatments become available for the prevention of disability accumulation in patients with progressive MS. In this short review, we discuss the landscape of existing therapies with an eye to the future when planning for optimal DMT sequencing. While no cure exists for MS, efforts are being directed toward research in neuroregeneration with the hope for positive outcomes.