Temporal profile of lymphocyte counts and relationship with infections with fingolimod therapy

Real World Lab Data: Patterns of Lymphocyte Counts in Fingolimod Treated Patients

Objective:

Fingolimod is approved for the treatment of highly active relapsing remitting multiple sclerosis (MS) patients and acts by its unique mechanism of action via sphingosine-1-phosphate receptor-modulation. Although fingolimod-associated lymphopenia is a well-known phenomenon, the exact cause for the intra- and inter-individual differences of the fluctuation of lymphocyte count and its subtypes is still subject of debate. In this analysis, we aim to estimate the significance of the individual variation of distinct lymphocyte subsets for differences in absolute lymphocyte decrease in fingolimod treated patients and discuss how different lymphocyte subset patterns are related to clinical presentation in a long-term real life setting.

Methods/Design:

One hundred and thirteen patients with MS were characterized by complete blood cell count and immune cell phentopying of peripheral lymphocyte subsets before, at month 1 and every 3 months up to 36 months of fingolimod treatment. In addition, patients were monitored regarding clinical parameters (relapses, disability, MRI).

Results:

There was no significant association of baseline lymphocyte count and lymphocyte subtypes with lymphocyte decrease after fingolimod start. The initial drop of the absolute lymphocyte count could not predict the level of lymphocyte count during steady state on fingolimod. Variable CD8+ T cell and NK cell counts account for the remarkable intra- and inter-individual differences regarding initial drop and steady state level of lymphocyte count during fingolimod treatment, whereas CD4+ T cells and B cells mostly present a quite uniform decrease in all treated patients. Selected patients with lymphocyte count >1.0 GPT/l differed by higher CD8+ T cells and NK cell counts compared to lymphopenic patients but presented comparable clinical effectiveness during treatment.

Conclusion:

Monitoring of the absolute lymphocyte count at steady state seems to be a rough estimate of fingolimod induced lymphocyte redistribution. Our results suggest, that evaluation of distinct lymphocyte subsets as CD4+ T cells allow a more detailed evaluation to weigh and interpret degree of lymphopenia and treatment response in fingolimod treated patients.

Benefit-Risk Profile of Sphingosine-1-Phosphate Receptor Modulators in Relapsing and Secondary Progressive Multiple Sclerosis

Since the approval of fingolimod, several selective sphingosine-1-phosphate receptor modulators have entered clinical development for multiple sclerosis. However, side effects can occur with sphingosine-1-phosphate receptor modulators. By considering short-term data across the drug class and longer term fingolimod data, we aim to highlight the potential of sphingosine-1-phosphate receptor modulators in multiple sclerosis, while offering reassurance that their benefit–risk profiles are suitable for long-term therapy. Short-term fingolimod studies demonstrated the efficacy of this drug class, showed that cardiac events upon first-dose administration are transient and manageable, and showed that serious adverse events are rare. Early-phase studies of selective sphingosine-1-phosphate receptor modulators also show efficacy with a similar or improved safety profile, and treatment initiation effects were reduced with dose titration. Longer term fingolimod studies demonstrated sustained efficacy and raised no new safety concerns, with no increases in macular edema, infection, or malignancy rates. Switch studies identified no safety concerns and greater patient satisfaction and persistence with fingolimod when switching from injectable therapies with no washout period. Better outcomes were seen with short than with long washouts when switching from natalizumab. The specific immunomodulatory effects of sphingosine-1-phosphate receptor modulators are consistent with the low observed rates of long-term, drug-related adverse effects with fingolimod. Short-term data for selective sphingosine-1-phosphate receptor modulators support their potential effectiveness in multiple sclerosis, and improved side-effect profiles may widen patient access to this drug class. The long-term safety, tolerability, and persistence profiles of fingolimod should reassure clinicians that sphingosine-1-phosphate receptor modulators are likely to be suitable for the long-term treatment of multiple sclerosis.

The First Dose of Fingolimod Affects Circulating Extracellular Vesicles in Multiple Sclerosis Patients

Extracellular vesicles (EVs) are membrane-bound particles involved in intercellular communication. They carry proteins, lipids, and nucleotides such as microRNAs (miRNAs) from the secreting cell that can modulate target cells. We and others have previously described the presence of EVs in peripheral blood of multiple sclerosis (MS) patients and postulated them as novel biomarkers. However, their immune function in MS pathogenesis and the effect during the onset of new immunomodulatory therapies on EVs remain elusive. Here, we isolated plasma EVs from fingolimod-treated MS patients in order to assess whether EVs are affected by the first dose of the treatment. We quantified EVs, analyzed their miRNA cargo, and checked their immune regulatory function. Results showed an elevated EV concentration with a dramatic change in their miRNA cargo 5 h after the first dose of fingolimod. Besides, EVs obtained prior to fingolimod treatment showed an increased immune regulatory activity compared to EVs obtained 5 h post-treatment. This work suggests that EVs are implicated in the mechanism of action of immunomodulatory treatments from the initial hours and opens a new avenue to explore a potential use of EVs for early treatment monitoring.

Sequencing of disease-modifying therapies for relapsing-remitting multiple sclerosis: a theoretical approach to optimizing treatment

Multiple sclerosis (MS) is a chronic disease which usually begins in young adulthood and is a lifelong condition. Individuals with MS experience physical and cognitive disability resulting from inflammation and demyelination in the central nervous system. Over the past decade, several disease-modifying therapies (DMTs) have been approved for the management of relapsing-remitting MS (RRMS), which is the most prevalent phenotype. The chronic nature of the disease and the multiple treatment options make benefit-risk-based sequencing of therapy essential to ensure optimal care. The efficacy and short- and long-term risks of treatment differ for each DMT due to their different mechanism of action on the immune system. While transitioning between DMTs, in addition to immune system effects, factors such as age, disease duration and severity, disability status, monitoring requirements, preference for the route of administration, and family planning play an important role. Determining a treatment strategy is therefore challenging as it requires careful consideration of the differences in efficacy, safety and tolerability, while at the same time minimizing risks of immune modulation. In this review, we discuss a sequencing approach for treating RRMS, with importance given to the long-term risks and individual preference when devising a treatment plan. Evidence-based strategies to counter breakthrough disease are also addressed.

Immune Cell Profiling During Switching from Natalizumab to Fingolimod Reveals Differential Effects on Systemic Immune-Regulatory Networks and on Trafficking of Non-T Cell Populations into the Cerebrospinal Fluid-Results from the ToFingo Successor Study

Leukocyte sequestration is an established therapeutic concept in multiple sclerosis (MS) as represented by the trafficking drugs natalizumab (NAT) and fingolimod (FTY). However, the precise consequences of targeting immune cell trafficking for immunoregulatory network functions are only incompletely understood. In the present study, we performed an in-depth longitudinal characterization of functional and phenotypic immune signatures in peripheral blood (PB) and cerebrospinal fluid (CSF) of 15 MS patients during switching from long-term NAT to FTY treatment after a defined 8-week washout period within a clinical trial (ToFingo successor study; ClinicalTrials.gov: NCT02325440). Unbiased visualization and analysis of high-dimensional single cell flow-cytometry data revealed that switching resulted in a profound alteration of more than 80% of investigated innate and adaptive immune cell subpopulations in the PB, revealing an unexpectedly broad effect of trafficking drugs on peripheral immune signatures. Longitudinal CSF analysis demonstrated that NAT and FTY both reduced T cell subset counts and proportions in the CSF of MS patients with equal potency; NAT however was superior with regard to sequestering non-T cell populations out of the CSF, including B cells, natural killer cells and inflammatory monocytes, suggesting that disease exacerbation in the context of switching might be driven by non-T cell populations. Finally, correlation of our immunological data with signs of disease exacerbation in this small cohort suggested that both (i) CD49d expression levels under NAT at the time of treatment cessation and (ii) swiftness of FTY-mediated effects on immune cell subsets in the PB together may predict stability during switching later on.

Reconstitution of the peripheral immune repertoire following withdrawal of fingolimod

BACKGROUND

Following fingolimod cessation, immune reconstitution or lack thereof may have consequences for disease rebound or safety of commencing alternative therapies.

OBJECTIVE

To examine the degree and profile of peripheral blood lymphocyte reconstitution following fingolimod withdrawal.

METHODS

Total lymphocyte counts (TLC) and CD4+/CD8+ T-cell counts were measured in 18 multiple sclerosis (MS) patients pre-treatment, on fingolimod, and up to 8-9 months post-cessation. T-cell subsets were analyzed using flow cytometry.

RESULTS

At 2-week post-fingolimod cessation, TLC reconstitution was variable and not correlated with age, treatment duration, pre-, or on-treatment TLC. Despite normalization of TLC and CD4+:CD8+ ratios over months, naive subsets remained lower and effector memory subsets higher in frequency compared with pre-treatment. Drug-induced increases in ratios of regulatory to pathogenic Th17-containing central memory populations appeared to rapidly return to baseline.

CONCLUSION

Early peripheral lymphocyte reconstitution after fingolimod withdrawal remains partial and heterogeneous. Relative frequencies of circulating naive and memory T-cell subsets may not recover for many months, even when clinical laboratory tests have normalized. Analyzing specific components of the peripheral immune repertoire helps define the overall immune status of patients. To be determined is whether assessment of such immune measures will have implications for the timing and safety of commencing alternative therapies.

Cutaneous cryptococcosis in a patient taking fingolimod for multiple sclerosis: Here come the opportunistic infections?

BACKGROUND

Fingolimod is an oral disease-modifying therapy for relapsing forms of multiple sclerosis, which acts by sequestering lymphocytes within lymph nodes.

OBJECTIVE

To describe a case of extrapulmonary cryptococcosis in a patient taking fingolimod.

METHODS

Case report.

RESULTS

A 47-year-old man developed a non-healing skin lesion approximately 16 months after starting treatment with fingolimod. Biopsy revealed cryptococcosis. Fingolimod was discontinued and the lesion resolved with antifungal therapy.

CONCLUSION

Despite few reported opportunistic infections in the pivotal clinical trials and first few years post-marketing, there has been a recent increase in reported AIDS-defining illnesses in patients taking fingolimod. Neurologists should be alert for opportunistic infections in their patients using this medication.

Risk factors for fingolimod-induced lymphopenia in multiple sclerosis

Background

Lymphopenia is a well-known adverse event of fingolimod, a disease-modifying drug for multiple sclerosis (MS).

Objectives

The objective of this paper is to investigate risk factors for predicting fingolimod-induced lymphopenia in MS by frequent hematological monitoring.

Methods

We retrospectively reviewed data of fingolimod-treated MS patients. Data assessed were sex, age, disease duration, medication history, body mass index, all attacks, Kurtzke’s Expanded Disability Status Scale score, and absolute lymphocyte count (ALC) within two days before initiating fingolimod (baseline), on the day after first administration (day 2), and at least every other month after initiating fingolimod therapy.

Results

Of 41 MS patients, marked lymphopenia (ALC <200/µl) was confirmed in 12 patients (lymphopenia group) within one year. A significantly more frequent history of treatment with any interferon-beta and lower median baseline ALC was observed in the lymphopenia group than in the non-lymphopenia group (n = 29) (91.7% vs. 44.8%; p = 0.006 and 1469/µl vs. 1879/µl; p = 0.005). An ALC of ≤952/μl on day 2 was the most responsible risk factor for predicting marked lymphopenia (sensitivity, 92%; specificity, 76%; area under the curve, 0.823; p < 0.001).

Conclusions

Low baseline ALC and treatment history with any interferon-beta were risk factors for fingolimod-induced lymphopenia, possibly predicted from ALC on day 2.

ESCMID Study Group for Infections in Compromised Hosts (ESGICH) Consensus Document on the safety of targeted and biological therapies: an infectious diseases perspective (Immune checkpoint inhibitors, cell adhesion inhibitors, sphingosine-1-phosphate receptor modulators and proteasome inhibitors)

BACKGROUND

The present review is part of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) Study Group for Infections in Compromised Hosts (ESGICH) consensus document on the safety of targeted and biological therapies.

AIMS

To review, from an infectious diseases perspective, the safety profile of immune checkpoint inhibitors, LFA-3-targeted agents, cell adhesion inhibitors, sphingosine-1-phosphate receptor modulators and proteasome inhibitors, and to suggest preventive recommendations.

SOURCES

Computer-based Medline searches with MeSH terms pertaining to each agent or therapeutic family.

CONTENT

T-lymphocyte-associated antigen 4 (CTLA-4) and programmed death (PD)-1/PD-1 ligand 1 (PD-L1)-targeted agents do not appear to intrinsically increase the risk of infection but can induce immune-related adverse effects requiring additional immunosuppression. Although CD4⁺ T-cell lymphopenia is associated with alefacept, no opportunistic infections have been observed. Progressive multifocal leukoencephalopathy (PML) may occur during therapy with natalizumab (anti-α4-integrin monoclonal antibody (mAb)) and efalizumab (anti-CD11a mAb), but no cases have been reported to date with vedolizumab (anti-α4β7 mAb). In patients at high risk for PML (positive anti-JC polyomavirus serology with serum antibody index >1.5 and duration of therapy ≥48 months), the benefit-risk ratio of continuing natalizumab should be carefully considered. Fingolimod induces profound peripheral blood lymphopenia and increases the risk of varicella zoster virus (VZV) infection. Prophylaxis with (val)acyclovir and VZV vaccination should be considered. Proteasome inhibitors also increase the risk of VZV infection, and antiviral prophylaxis with (val)acyclovir is recommended. Anti-Pneumocystis prophylaxis may be considered in myeloma multiple patients with additional risk factors (i.e. high-dose corticosteroids).

IMPLICATIONS

Clinicians should be aware of the risk of immune-related adverse effects and PML in patients receiving immune checkpoint and cell adhesion inhibitors respectively.

Understanding Progressive Multifocal Leukoencephalopathy Risk in Multiple Sclerosis Patients Treated with Immunomodulatory Therapies: A Bird's Eye View

The increased use of newer potent immunomodulatory therapies for multiple sclerosis (MS), including natalizumab, fingolimod, and dimethyl fumarate, has expanded the patient population at risk for developing progressive multifocal leukoencephalopathy (PML). These MS therapies shift the profile of lymphocytes within the central nervous system (CNS) leading to increased anti-inflammatory subsets and decreased immunosurveillance. Similar to MS, PML is a demyelinating disease of the CNS, but it is caused by the JC virus. The manifestation of PML requires the presence of an active, genetically rearranged form of the JC virus within CNS glial cells, coupled with the loss of appropriate JC virus-specific immune responses. The reliability of metrics used to predict risk for PML could be improved if all three components, i.e., viral genetic strain, localization, and host immune function, were taken into account. Advances in our understanding of the critical lymphocyte subpopulation changes induced by these MS therapies and ability to detect viral mutation and reactivation will facilitate efforts to develop these metrics.

A systematic evaluation of the safety and toxicity of fingolimod for its potential use in the treatment of acute myeloid leukaemia

Treatment of acute myeloid leukaemia (AML) is challenging and emerging treatment options include protein phosphatase 2A (PP2A) activators. Fingolimod is a known PP2A activator that inhibits multiple signalling pathways and has been used extensively in patients with multiple sclerosis and other indications. The initial positive results of PP2A activators in vitro and mouse models of AML are promising; however, its safety for use in AML has not been assessed. From human studies of fingolimod in other indications, it is possible to evaluate whether the safety and toxicity profile of the PP2A activators will allow their use in treating AML. A literature review was carried out to assess safety before the commencement of Phase I trials of the PP2A activator Fingolimod in AML. From human studies of fingolimod in other indications, it is possible to evaluate whether the safety and toxicity profile of the PP2A activators will allow their use in treating AML. A systematic review of published literature in Medline, EMBASE and the Cochrane Library of critical reviews was carried out. International standards for the design and reporting of search strategies were followed. Search terms and medical subject headings used in trials involving PP2A activators as well as a specific search were performed for ‘adverse events’, ‘serious adverse events’, ‘delays in treatment’, ‘ side effects’ and ‘toxicity’ for primary objectives. Database searches were limited to papers published in the last 12 years and available in English. The search yielded 677 articles. A total of 69 journal articles were identified as relevant and included 30 clinical trials, 24 review articles and 15 case reports. The most frequently reported adverse events were nausea, diarrhoea, fatigue, back pain, influenza viral infections, nasopharyngitis and bronchitis. Specific safety concerns include monitoring of the heart rate and conduction at commencement of treatment as cardiotoxicity has been reported. There is little evidence to suggest specific bone marrow toxicity. Lymophopenia is a desired effect in the management of multiple sclerosis, but may have implications in patients with acute leukaemia as it may potentially increase susceptibility to viral infections such as influenza. Fingolimod is a potential treatment option for AML with an acceptable risk to benefit ratio, given its lack of bone marrow toxicity and the relatively low rate of serious side effects. As most patients with AML are elderly, specific monitoring for cardiac toxicity as well as infection would be required.

Gender differences in safety issues during Fingolimod therapy: Evidence from a real-life Relapsing Multiple Sclerosis cohort

OBJECTIVE

Benefits and risks of new therapies in Multiple Sclerosis (MS) must be balanced carefully and tailored to patients. We aimed to describe our experience with Fingolimod (FTY), correlating demographics, clinical and hematological features of the Relapsing MS (RMS) cohort with the occurring Adverse Events (AEs).

MATERIAL AND METHODS

Pretreatment screening tests, cardiological observation, and safety follow-up data were analyzed in 225 RMS patients. Changes in continuous data were analyzed post hoc with Wilcoxon ranks test; categorical variables were examined using McNemar test. Two-way repeated-measures analysis of variance (ANOVA) was used to analyze differences between baseline characteristic of the cohorts and Liver Function Tests (LFT) alterations. Binary logistic regression models were used to identify which of the baseline factors influenced LFT alterations and the occurrence of infections.

RESULTS

During 2 years of follow-up 24 patients (10%) interrupted FTY. Discontinuation most often was due to AEs (n = 14) or breakthrough disease (n = 5). The most frequently AEs were infections (10.6%). After the first year patients showing an infectious episode were mostly female (p = .04). The infections did not correlate with the decrease in white blood cells or to lymphocyte count. AST and ALT alterations ​​were observed mostly in males (p = .002 and p = .01, respectively), and increase in GGT ​​was reported in subjects older at FTY beginning (p < .05).

CONCLUSIONS

For a patient-centered safety monitoring of FTY, we may apply gender-specific warnings, for the detection of transaminases abnormalities and infectious episodes.

Reversibility of the effects of natalizumab on peripheral immune cell dynamics in MS patients

OBJECTIVE

To characterize the reversibility of natalizumab-mediated changes in pharmacokinetics/pharmacodynamics in patients with multiple sclerosis (MS) following therapy interruption.

METHODS

Pharmacokinetic/pharmacodynamic data were collected in the Safety and Efficacy of Natalizumab in the Treatment of Multiple Sclerosis (AFFIRM) (every 12 weeks for 116 weeks) and Randomized Treatment Interruption of Natalizumab (RESTORE) (every 4 weeks for 28 weeks) studies. Serum natalizumab and soluble vascular cell adhesion molecule-1 (sVCAM-1) were measured using immunoassays. Lymphocyte subsets, α4-integrin expression/saturation, and vascular cell adhesion molecule-1 (VCAM-1) binding were assessed using flow cytometry.

RESULTS

Blood lymphocyte counts (cells/L) in natalizumab-treated patients increased from 2.1 × 10⁹ to 3.5 × 10⁹. Starting 8 weeks post last natalizumab dose, lymphocyte counts became significantly lower in patients interrupting treatment than in those continuing treatment (3.1 × 10⁹ vs 3.5 × 10⁹; p = 0.031), plateauing at prenatalizumab levels from week 16 onward. All measured cell subpopulation, α4-integrin expression/saturation, and sVCAM changes demonstrated similar reversibility. Lymphocyte counts remained within the normal range. Ex vivo VCAM-1 binding to lymphocytes increased until ≈16 weeks after the last natalizumab dose, then plateaued, suggesting reversibility of immune cell functionality. The temporal appearance of gadolinium-enhancing lesions was consistent with pharmacodynamic marker reversal.

CONCLUSIONS

Natalizumab's effects on peripheral immune cells and pharmacodynamic markers were reversible, with changes starting 8 weeks post last natalizumab dose; levels returned to those observed/expected in untreated patients ≈16 weeks post last dose. This reversibility differentiates natalizumab from MS treatments that require longer reconstitution times. Characterization of the time course of natalizumab's biological effects may help clinicians make treatment sequencing decisions.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that the pharmacodynamic markers of natalizumab are reversed ≈16 weeks after stopping natalizumab.

Circulating lymphocyte levels and relationship with infection status in patients with relapsing-remitting multiple sclerosis treated with daclizumab beta

BACKGROUND

Reversible lymphocyte count reductions have occurred following daclizumab beta treatment for relapsing-remitting multiple sclerosis.

OBJECTIVE

To analyse total and differential lymphocyte levels and relationship with infection status.

METHODS

In DECIDE, blood samples were collected at 12-week intervals from daclizumab beta- ( n = 919) or intramuscular interferon beta-1a-treated ( n = 922) patients. Infections/serious infections were assessed proximate to grade 2/3 lymphopenia or low CD4⁺/CD8⁺ T-cell counts. Total safety population (TSP) data were additionally analysed from the entire clinical development programme ( n = 2236).

RESULTS

Over 96 weeks in DECIDE, mean absolute lymphocyte count (ALC), CD4⁺ and CD8⁺ T-cell counts decreased <10% (7.1% vs 1.6%, 9.7% vs 2.0%, 9.3% vs 5.9%: daclizumab beta vs interferon beta-1a, respectively); shifts to ALC below lower limit of normal occurred in 13% versus 15%, respectively. Grade 3 lymphopenia was uncommon (TSP: <1%) and transient. Lymphocyte changes generally occurred within 24 weeks after treatment initiation and were reversible within 12 weeks of discontinuation. In DECIDE, mean CD4⁺/CD8⁺ T-cell counts were similar regardless of infection status. TSP data were consistent with DECIDE.

CONCLUSION

When observed, ALC and CD4⁺/CD8⁺ T-cell count decreases in daclizumab beta-treated patients were generally mild-to-modest, reversible upon treatment discontinuation and not associated with increased risk of infections, including opportunistic infections.

The sequence of disease-modifying therapies in relapsing multiple sclerosis: safety and immunologic considerations

The treatment landscape for relapsing forms of multiple sclerosis (RMS) has expanded considerably over the last 10 years with the approval of multiple new disease-modifying therapies (DMTs), and others in late-stage clinical development. All DMTs for RMS are believed to reduce central nervous system immune-mediated inflammatory processes, which translate into demonstrable improvement in clinical and radiologic outcomes. However, some DMTs are associated with long-lasting effects on the immune system and/or serious adverse events, both of which may complicate the use of subsequent therapies. When customizing a treatment program, a benefit–risk assessment must consider multiple factors, including the efficacy of the DMT to reduce disease activity, the short- and long-term safety and immunologic profiles of each DMT, the criteria used to define switching treatment, and the risk tolerance of each patient. A comprehensive benefit–risk assessment can only be achieved by evaluating the immunologic, safety, and efficacy data for DMTs in the controlled clinical trial environment and the postmarketing clinical practice setting. This review is intended to help neurologists make informed decisions when treating RMS by summarizing the known data for each DMT and raising awareness of the multiple considerations involved in treating people with RMS throughout the entire course of their disease.

Fingolimod hydrochloride for the treatment of relapsing remitting multiple sclerosis

INTRODUCTION

Fingolimod was the first oral and the first in class disease modifying treatment in multiple sclerosis that acts as sphingosine-1-phospathe receptor agonist. Since approval in 2010 there is a growing experience with fingolimod use in clinical practice, but also next-generation sphingosin-1-receptor agonists in ongoing clinical trials. Growing evidence demonstrates additional effects beyond impact on lymphocyte circulation, highlighting further promising targets in multiple sclerosis therapy. Areas covered: Here we present a systematic review using PubMed database searching and expert opinion on fingolimod use in clinical practice. Long-term data of initial clinical trials and post-marketing evaluations including long-term efficacy, safety, tolerability and management especially within growing disease modifying treatment options and pre-treatment constellation in multiple sclerosis patients are critically discussed. Furthermore novel findings in mechanism of actions and prospective on additional use in progressive forms in multiple sclerosis are presented. Expert opinion: There is an extensive long-term experience on fingolimod use in clinical practice demonstrating the favorable benefit-risk of this drug. Using a defined risk management approach experienced MS clinicians should apply fingolimod after critical choice of patients and review of clinical aspects. Further studies are essential to discuss additional benefit in progressive forms in multiple sclerosis.

Age as a risk factor for early onset of natalizumab-related progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy (PML) is a rare but potentially fatal opportunistic infection that arises almost exclusively in immunocompromised patients or in those treated with monoclonal antibodies, especially natalizumab. Here, we aimed at exploring if age at treatment start affects the time to onset of natalizumab-related PML. PubMed was searched for the terms "natalizumab and progressive multifocal leukoencephalopathy" in articles published from January 2005 to March 2017. We collected information on each identified PML case, including demographic and clinical variables at natalizumab start and at PML onset. The number of natalizumab infusions until PML onset was investigated in time-to-event analyses. We identified 238 cases who developed PML after a median number of 33 natalizumab infusions (range 6 to 103). Risk factors for an earlier onset of natalizumab-related PML were prior immunosuppressant exposure (hazard ratio [HR] = 1.43, p = 0.017) and older age at treatment start (HR = 1.02, p = 0.016). In particular, patients older than 50 years had a more than doubled-increased risk for an earlier PML onset (HR = 2.11, p = 0.006). Our findings suggest that the age at natalizumab start may represent a risk factor for an earlier PML onset, thus claiming further investigations about the interplay between immunosenescence and MS treatments.

Neurological safety of fingolimod: An updated review

Fingolimod (FTY) is the first oral medication approved for treatment of relapsing–remitting multiple sclerosis (RRMS). Its effectiveness and safety were confirmed in several phase III clinical trials, but proper evaluation of safety in the real patient population requires long‐term post‐marketing monitoring. Since the approval of FTY for RRMS in Japan in 2011, it has been administered to approximately 5000 MS patients, and there have been side‐effect reports from 1750 patients. Major events included infectious diseases, hepatobiliary disorders, nervous system disorders and cardiac disorders. In the present review, we focus especially on central nervous system adverse events. The topics covered are: (i) clinical utility of FTY; (ii) safety profile; (iii) post‐marketing adverse events in Japan; (iv) white matter (tumefactive) lesions; (v) rebound after FTY withdrawal; (vi) relationship between FTY and progressive multifocal leukoencephalopathy; (vii) FTY and progressive multifocal leukoencephalopathy‐related immune reconstitution inflammatory syndrome; and (viii) neuromyelitis optica and leukoencephalopathy.

Neurotherapeutic Strategies for Multiple Sclerosis

Multiple sclerosis (MS) is the most common disabling neurologic disease of young adults. There are now 16 US Food and Drug Administration (FDA)-approved disease-modifying therapies for MS as well as a cohort of other agents commonly used in practice when conventional therapies prove inadequate. This article discusses approved FDA therapies as well as commonly used practice-based therapies for MS, as well as those therapies that can be used in patients attempting to become pregnant, or in patients with an established pregnancy, who require concomitant treatment secondary to recalcitrant disease activity.

Cerebral toxoplasmosis in an MS patient receiving Fingolimod

Multiple Sclerosis (MS) is an autoimmune disease in which lymphocytes target putative myelin antigens in the CNS, causing inflammation and neurodegeneration. Fingolimod (FTY720) is an immunosuppressive drug used as a second line therapy for relapsing forms of MS due to its safety profile and good response to treatment. Despite its safety, there are still concerns about the possibility of Fingolimod being linked to the development of opportunistic infections like disseminated varicella zoster infections and herpes simplex encephalitis. In this case report, we describe one patient with past medical history of MS in current treatment with Fingolimod for the last year which presents herself with hemiparesis, fever and fatigue. The initial MRI showed multiple demyelinating-like lesions that could have corresponded to the tumefactive form of MS relapse. The blood work up revealed leukopenia with lymphopenia and a CD4+ count of 200 cell/mm³. Treatment for acute relapse was initiated with little to no response. Further examination was carried by the clinicians, a lumbar puncture was performed and it showed pleocytosis with increased protein levels. Later, several serologic studies were performed and both IgM and IgG antibodies for Toxoplasma were positive. Diagnosis of cerebral toxoplasmosis was made and there was no evidence of HIV infection or other causes of secondary immunodeficiency in this patient, except the use of fingolimod. Evidence of decreased levels of CD4+ due to Fingolimod use is concerning. The risk of opportunistic infections in these patients must be considered in order to start or continue therapy with these agents. Further studies are needed to determine the percentage of the population at risk of immunosuppression and its long-term consequences as well as new actions to prevent infections.

Results From the First-in-Human Study With Ozanimod, a Novel, Selective Sphingosine-1-Phosphate Receptor Modulator

The sphingosine-1-phosphate 1 receptor (S1P_1R ) is expressed by lymphocytes, dendritic cells, and vascular endothelial cells and plays a role in the regulation of chronic inflammation and lymphocyte egress from peripheral lymphoid organs. Ozanimod is an oral selective modulator of S1P_1R and S1P_5R receptors in clinical development for the treatment of chronic immune-mediated, inflammatory diseases. This first-in-human study characterized the safety, pharmacokinetics (PK), and pharmacodynamics (PD) of ozanimod in 88 healthy volunteers using a range of single and multiple doses (7 and 28 days) and a dose-escalation regimen. Ozanimod was generally well tolerated up to a maximum single dose of 3 mg and multiple doses of 2 mg/d, with no severe adverse events (AEs) and no dose-limiting toxicities. The most common ozanimod-related AEs included headache, somnolence, dizziness, nausea, and fatigue. Ozanimod exhibited linear PK, high steady-state volume of distribution (73-101 L/kg), moderate oral clearance (204-227 L/h), and an elimination half-life of approximately 17 to 21 hours. Ozanimod produced a robust dose-dependent reduction in total peripheral lymphocytes, with a median decrease of 65% to 68% observed after 28 days of dosing at 1 and 1.5 mg/d, respectively. Ozanimod selectivity affected lymphocyte subtypes, causing marked decreases in cells expressing CCR7 and variable decreases in subsets lacking CCR7. A dose-dependent negative chronotropic effect was observed following the first dose, with the dose-escalation regimen attenuating the first-dose negative chronotropic effect. Ozanimod safety, PK, and PD properties support the once-daily regimens under clinical investigation.

FTY720 inhibits mesothelioma growth in vitro and in a syngeneic mouse model

BACKGROUND

Malignant mesothelioma (MM) is a very aggressive type of cancer, with a dismal prognosis and inherent resistance to chemotherapeutics. Development and evaluation of new therapeutic approaches is highly needed. Immunosuppressant FTY720, approved for multiple sclerosis treatment, has recently raised attention for its anti-tumor activity in a variety of cancers. However, its therapeutic potential in MM has not been evaluated yet.

METHODS

Cell viability and anchorage-independent growth were evaluated in a panel of MM cell lines and human mesothelial cells (HM) upon FTY720 treatment to assess in vitro anti-tumor efficacy. The mechanism of action of FTY720 in MM was assessed by measuring the activity of phosphatase protein 2A (PP2A)-a major target of FTY720. The binding of the endogenous inhibitor SET to PP2A in presence of FTY720 was evaluated by immunoblotting and immunoprecipitation. Signaling and activation of programmed cell death were evaluated by immunoblotting and flow cytometry. A syngeneic mouse model was used to evaluate anti-tumor efficacy and toxicity profile of FTY720 in vivo.

RESULTS

We show that FTY720 significantly suppressed MM cell viability and anchorage-independent growth without affecting normal HM cells. FTY720 inhibited the phosphatase activity of PP2A by displacement of SET protein, which appeared overexpressed in MM, as compared to HM cells. FTY720 promoted AKT dephosphorylation and Bcl-2 degradation, leading to induction of programmed cell death, as demonstrated by caspase-3 and PARP activation, as well as by cytochrome c and AIF intracellular translocation. Moreover, FTY720 administration in vivo effectively reduced tumor burden in mice without apparent toxicity.

CONCLUSIONS

Our preclinical data indicate that FTY720 is a potentially promising therapeutic agent for MM treatment.

Infectious Complications of Novel Multiple Sclerosis Therapies

PURPOSE OF REVIEW

Multiple sclerosis (MS) is an autoimmune demyelinating disease of the central nervous system most often characterized by clinical relapses and periods of remission.

RECENT FINDINGS

The past decade has seen a dramatic increase in disease-modifying therapies for MS. Fourteen FDA-approved immunomodulatory drugs are currently available, and more medications are in development. A growing number of reported opportunistic infections, including progressive multifocal leukoencephalopathy (PML), highlight the serious complications of these new drugs and the need for specific screening guidelines. Using data from Phase II and III randomized controlled trials, case reports, drug manufacturing data, and clinical experience, we outline the most common and serious infections associated with novel MS therapies.

Fingolimod alters the transcriptome profile of circulating CD4+ cells in multiple sclerosis

Multiple sclerosis is a demyelinating disease affecting the central nervous system. T cells are known to contribute to this immune-mediated condition. Fingolimod modulates sphingosine-1-phosphate receptors, thereby preventing the egress of lymphocytes, especially CCR7-expressing CD8+ and CD4+ T cells, from lymphoid tissues. Using Affymetrix Human Transcriptome Arrays (HTA 2.0), we performed a transcriptome profiling analysis of CD4+ cells obtained from the peripheral blood of patients with highly active relapsing-remitting multiple sclerosis. The samples were drawn before the first administration of fingolimod as well as 24 hours and 3 months after the start of therapy. Three months after treatment initiation, 890 genes were found to be differentially expressed with fold-change >2.0 and t-test p-value < 0.001, among them several microRNA precursors. A subset of 272 genes were expressed at lower levels, including CCR7 as expected, while 618 genes showed an increase in expression, e.g., CCR2, CX3CR1, CD39, CD58 as well as LYN, PAK1 and TLR2. To conclude, we studied the gene expression of CD4+ cells to evaluate the effects of fingolimod treatment, and we identified 890 genes to be altered in expression after continuous drug administration. T helper cells circulating in the blood during fingolimod therapy present a distinct gene expression signature.

Half-dose fingolimod for treating relapsing-remitting multiple sclerosis: Observational study

Objectives:

To investigate the efficacy and safety of fingolimod (FTY) 0.5 mg administered every other day (FTY-EOD) compared to every day (FTY-ED) in multiple sclerosis patients.

Methods:

Multicentre retrospective observational study. Clinical, laboratory and neuroimaging data were consecutively collected from 60 FTY-EOD and 63 FTY-ED patients. Baseline characteristics were compared using logistic regression. Efficacy in preventing occurrence of relapses and demyelinating lesions was tested using propensity score–adjusted Cox and linear regressions.

Results:

Weight was inversely associated with risk of switch to FTY-EOD because of any reason (odds ratio (OR) = 0.94, 95% confidence interval (95% CI) = 0.89–0.99, p = 0.026), and female sex and lower baseline lymphocyte count were positively associated with switch because of lymphopenia. Compared to FTY-ED patients, FTY-EOD patients were at higher risk of developing relapses (hazard ratio (HR) = 2.98, 95% CI = 1.07–8.27, p  = 0.036) and either relapses or new magnetic resonance imaging (MRI) demyelinating lesions (combined outcome, HR = 2.07, 95% CI = 1.06–4.08, p  = 0.034). Within FTY-EOD, treatment with natalizumab before FTY and lower age were positively associated with risk of developing relapses and combined outcome, respectively (HR = 25.71, 95% CI = 3.03–217.57, p = 0.002 and HR = 0.85, 95% CI = 0.77–0.96, p  = 0.005). FTY-EOD was overall well tolerated.

Conclusion:

Disease reactivation was observed in a significant proportion of patients treated with FTY-EOD. Neurologists should be cautious when reducing FTY administration to every other day, especially in younger patients and those previously treated with natalizumab.

Safety and tolerability of fingolimod in patients with relapsing-remitting multiple sclerosis: results of an open-label clinical trial in Italy

The safety profile of fingolimod is well established in clinical trials and post-marketing studies. This study aimed to evaluate the safety and tolerability of fingolimod in a cohort of Italian patients with relapsing-remitting multiple sclerosis (RRMS). This is a non-comparative, open-label, multicentre, interventional study conducted in patients with RRMS with no suitable alternative treatment option. Safety and tolerability of fingolimod 0.5 mg were assessed by recording adverse events (AEs) and serious AEs (SAEs). Of the 906 patients enrolled in the study, 91 % of the patients completed the study. AEs and SAEs were reported in 35.4 and 2.9 % of the patients, respectively. Most common AEs reported were headache (4.1 %), influenza (2.1 %), lymphopenia (1.8 %), asthenia (1.8 %) and pyrexia (1.8 %). Increased alanine aminotransferase levels and hypertension were reported as AE in 1.0 and 1.4 % of the patients, respectively. Macular oedema was reported in three patients. These results emphasize the safety of fingolimod in patients representing the real-world clinical practice in the Italian population. Fingolimod was safe and well tolerated in this population, which, compared to those enrolled in pivotal trials in terms of concomitant diseases and used medications, is broader.

TRIAL REGISTRATION

EudraCT 2011-000770-60.

High-Resolution Expression Profiling of Peripheral Blood CD8+ Cells in Patients with Multiple Sclerosis Displays Fingolimod-Induced Immune Cell Redistribution

Fingolimod, a sphingosine-1-phosphate (S1P) receptor modulator, is an oral drug approved for the treatment of active relapsing-remitting multiple sclerosis (RRMS). It selectively inhibits the egress of lymphocytes from lymph nodes. We studied the changes in the transcriptome of peripheral blood CD8⁺ cells to unravel the effects at the molecular level during fingolimod therapy. We separated CD8⁺ cells from the blood of RRMS patients before the first dose of fingolimod as well as 24 h and 3 months after the start of therapy. Changes in the expression of coding and non-coding genes were measured with high-density Affymetrix Human Transcriptome Array (HTA) 2.0 microarrays. Differentially expressed genes in response to therapy were identified by t test and fold change and analyzed for their functions and molecular interactions. No gene was expressed at significantly higher or lower levels 24 h after the first administration of fingolimod compared to baseline. However, after 3 months of therapy, 861 transcripts were found to be differentially expressed, including interleukin and chemokine receptors. Some of the genes are associated to the S1P pathway, such as the receptor S1P5 and the kinase MAPK1, which were significantly increased in expression. The fingolimod-induced transcriptome changes reflect a shift in the proportions of CD8⁺ T cell subsets, with CCR7^- effector memory T cells being relatively increased in frequency in the blood of fingolimod-treated patients. In consequence, CCR7 mRNA levels were reduced by >80 % and genes involved in T cell activation and lymphocyte cytotoxicity were increased in expression. Gene regulatory programs caused by downstream S1P signaling had only minor effects.

Immunologic mechanisms of fingolimod and the role of immunosenescence in the risk of cryptococcal infection: A case report and review of literature

BACKGROUND

Fingolimod is a disease-modifying agent used in the treatment of relapsing/remitting multiple sclerosis. In MS clinical studies, the overall rate of infections in fingolimod group was overall similar to placebo, except for slightly more common lower respiratory tract infections and to a lesser extent HSV. Recently, an increasing number of cryptococcal infections associated with a long-term use of this medication have been reported.

METHODS

We reviewed literature for cases of cryptococcal infection associated with the use of fingolimod and reported a case at our institution, as well as carefully evaluated the established immune mechanisms of the medication and discussed new insights into its short-term and long-term immunologic effects that may become important in the context of risk of infection.

RESULTS

Unique characteristics of cryptococcal pathogen, its immune escape mechanisms, its ability to establish a latent infection with a potential for later reactivation, fingolimod's effects on many lines of immune system, both quantitatively and qualitatively, duration of therapy, and long-term effects of fingolimod, not previously described, in conjunction with effects of natural immunosenescence of the patient population, that appears to be most at risk, may be meaningful in further understanding the risk of infection with long-term use of fingolimod in people of older age.

Clinical pharmacology, efficacy, and safety aspects of sphingosine-1-phosphate receptor modulators

INTRODUCTION

Sphingosine-1-phosphate (S1P) receptor modulators, of which one has received marketing approval and several others are in clinical development, display promising potential in the treatment of a spectrum of autoimmune diseases.

AREAS COVERED

Administration of S1P1 receptor modulators leads to functional receptor antagonism triggering sustained inhibition of the egress of lymphocytes from lymphoid organs. First-dose administration is associated with transient cardiovascular effects. We compiled and discussed available pharmacokinetic, pharmacodynamic, and safety data of selective and non-selective S1P receptor modulators that were investigated in recent years.

EXPERT OPINION

The safety profile of S1P receptor modulators is considered better than other classes of immunomodulators and was further improved by the development of up-titration regimens to mitigate first-dose effects. S1P receptor modulators display similar pharmacodynamic effects but have very different pharmacokinetic profiles. Drugs with a rapid elimination are of interest in case of opportunistic infections or pregnancy, whereas the need of re-initiation of up-titration in case of treatment interruption can present a challenge.

Ozanimod Induction and Maintenance Treatment for Ulcerative Colitis

BACKGROUND

Ozanimod (RPC1063) is an oral agonist of the sphingosine-1-phosphate receptor subtypes 1 and 5 that induces peripheral lymphocyte sequestration, potentially decreasing the number of activated lymphocytes circulating to the gastrointestinal tract.

METHODS

We conducted a double-blind, placebo-controlled phase 2 trial of ozanimod in 197 adults with moderate-to-severe ulcerative colitis. Patients were randomly assigned, in a 1:1:1 ratio, to receive ozanimod at a dose of 0.5 mg or 1 mg or placebo daily for up to 32 weeks. The Mayo Clinic score was used to measure disease activity on a scale from 0 to 12, with higher scores indicating more severe disease; subscores range from 0 to 3, with higher scores indicating more severe disease. The primary outcome was clinical remission (Mayo Clinic score ≤2, with no subscore >1) at 8 weeks.

RESULTS

The primary outcome occurred in 16% of the patients who received 1 mg of ozanimod and in 14% of those who received 0.5 mg of ozanimod, as compared with 6% of those who received placebo (P=0.048 and P=0.14, respectively, for the comparison of the two doses of ozanimod with placebo). Differences in the primary outcome between the group that received 0.5 mg of ozanimod and the placebo group were not significant; therefore, the hierarchical testing plan deemed the analyses of secondary outcomes exploratory. Clinical response (decrease in Mayo Clinic score of ≥3 points and ≥30% and decrease in rectal-bleeding subscore of ≥1 point or a subscore ≤1) at 8 weeks occurred in 57% of those receiving 1 mg of ozanimod and 54% of those receiving 0.5 mg, as compared with 37% of those receiving placebo. At week 32, the rate of clinical remission was 21% in the group that received 1 mg of ozanimod, 26% in the group that received 0.5 mg of ozanimod, and 6% in the group that received placebo; the rate of clinical response was 51%, 35%, and 20%, respectively. At week 8, absolute lymphocyte counts declined 49% from baseline in the group that received 1 mg of ozanimod and 32% from baseline in the group that received 0.5 mg. The most common adverse events overall were anemia and headache.

CONCLUSIONS

In this preliminary trial, ozanimod at a daily dose of 1 mg resulted in a slightly higher rate of clinical remission of ulcerative colitis than placebo. The trial was not large enough or of sufficiently long duration to establish clinical efficacy or assess safety. (Funded by Receptos; TOUCHSTONE ClinicalTrials.gov number, NCT01647516.).

[The risk of varicella zoster virus infection in multiple sclerosis patients treated with fingolimod]

Fingolimod, a sphingosine-1-phosphate receptor modulator, inhibits the egress of CCR7-positive lymphocytes, including encephalitogenic lymphocytes, from lymph nodes and may sometimes cause lymphopenia. A recent study reported that varicella zoster virus reactivation occurred in the saliva of 20% of multiple sclerosis (MS) patients treated with fingolimod. I compared the risk of developing herpes zoster between 32 MS patients treated with fingolimod (FTY-MS) and 45 patients, including those with neuromyelitis optica spectrum disorder, horizontal hemianopsia without anti-aquaporin-4 antibodies, and myelitis with anti-myelin oligodendrocyte glycoprotein antibodies, treated with tacrolimus (TCR-NMO). The risk of developing herpes zoster in FTY-MS (40/1,000 patient-years) was significantly higher than that in TCR-NMO (6/1,000 patient-years) (P < 0.0001, odds ratio: 6.90). The incidence of herpes zoster of patients with rheumatoid arthritis treated with Tofacitinib in Asian countries has been shown to be higher than those of patients in the United States or European countries. It may be better to pay more attention to develop herpes zoster in Japanese MS patients treated with fingolimod.

Fingolimod for relapsing-remitting multiple sclerosis

BACKGROUND

Fingolimod was approved in 2010 for the treatment of patients with the relapsing-remitting (RR) form of multiple sclerosis (MS). It was designed to reduce the frequency of exacerbations and to delay disability worsening. Issues on its safety and efficacy, mainly as compared to other disease modifying drugs (DMDs), have been raised.

OBJECTIVES

To assess the safety and benefit of fingolimod versus placebo, or other disease-modifying drugs (DMDs), in reducing disease activity in people with relapsing-remitting multiple sclerosis (RRMS).

SEARCH METHODS

We searched the Cochrane Multiple Sclerosis and Rare Diseases of the Central Nervous System (CNS) Group's Specialised Trials Register and US Food and Drug Administration reports (15 February 2016).

SELECTION CRITERIA

Randomised controlled trials (RCTs) assessing the beneficial and harmful effects of fingolimod versus placebo or other approved DMDs in people with RRMS.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as expected by Cochrane.

MAIN RESULTS

Six RCTs met our selection criteria. The overall population included 5152 participants; 1621 controls and 3531 treated with fingolimod at different doses; 2061 with 0.5 mg, 1376 with 1.25 mg, and 94 with 5.0 mg daily. Among the controls, 923 participants were treated with placebo and 698 with others DMDs. The treatment duration was six months in three, 12 months in one, and 24 months in two trials. One study was at high risk of bias for blinding, three studies were at high risk of bias for incomplete outcome reporting, and four studies were at high risk of bias for other reasons (co-authors were affiliated with the pharmaceutical company). We retrieved 10 ongoing trials; four of them have been completed.Comparing fingolimod administered at the approved dose of 0.5 mg to placebo, we found that the drug at 24 months increased the probability of being relapse-free (risk ratio (RR) 1.44, 95% confidence interval (CI) (1.28 to 1.63); moderate quality of evidence), but it might lead to little or no difference in preventing disability progression (RR 1.07, 95% CI 1.02 to 1.11; primary clinical endpoints; low quality evidence). Benefit was observed for other measures of inflammatory disease activity including clinical (annualised relapse rate): rate ratio 0.50, 95% CI 0.40 to 0.62; moderate quality evidence; and magnetic resonance imaging (MRI) activity (gadolinium-enhancing lesions): RR of being free from (MRI) gadolinium-enhancing lesions: 1.36, 95% CI 1.27 to 1.45; low quality evidence.The mean change of MRI T2-weighted lesion load favoured fingolimod at 12 and 24 months.No significant increased risk of discontinuation due to adverse events was observed for fingolimod 0.5 mg compared to placebo at six and 24 months. The risk of fingolimod discontinuation was significantly higher compared to placebo for the dose 1.25 mg at 24 months (RR 1.93, 95% CI 1.48 to 2.52).No significant increased risk of discontinuation due to serious adverse events was observed for fingolimod 0.5 mg compared to placebo at six and 24 months. A significant increased risk of discontinuation due to serious adverse events was found for fingolimod 5.0 mg (RR 2.77, 95% CI 1.04 to 7.38) compared to placebo at six months.Comparing fingolimod 0.5 mg to intramuscular interferon beta-1a, we found moderate quality evidence that the drug at one year slightly increased the number of participants free from relapse (RR 1.18, 95% CI 1.09 to 1.27) or from gadolinium-enhancing lesions (RR 1.12, 95% CI 1.05 to 1.19), and decreased the relapse rate (rate ratio 0.48, 95% CI 0.34 to 0.70). We did not detect any advantage for preventing disability progression (RR 1.02, 95% CI 0.99 to 1.06; low quality evidence). We did not detect any significant difference for MRI T2-weighted lesion load change.We found a greater likelihood of participants discontinuing fingolimod, as compared to other DMDs, due to adverse events in the short-term (six months) (RR 3.21, 95% CI 1.16 to 8.86), but there was no significant difference versus interferon beta-1a at 12 months (RR 1.51, 95% CI 0.81 to 2.80; moderate quality evidence). A higher incidence of adverse events was suggestive of the lower tolerability rate of fingolimod compared to interferon-beta 1a.Quality of life was improved in participants after switching from a different DMD to fingolimod at six months, but this effect was not found compared to placebo at 24 months.All studies were sponsored by Novartis Pharma.

AUTHORS' CONCLUSIONS

Treatment with fingolimod compared to placebo in RRMS patients is effective in reducing inflammatory disease activity, but it may lead to little or no difference in preventing disability worsening. The risk of withdrawals due to adverse events requires careful monitoring of patients over time. The evidence on the risk/benefit profile of fingolimod compared with intramuscular interferon beta-1a was uncertain, based on a low number of head-to-head RCTs with short follow-up duration. The ongoing trial results will possibly satisfy these issues.

Fingolimod in the treatment of relapsing-remitting multiple sclerosis: long-term experience and an update on the clinical evidence

Since the approval in 2010 of fingolimod 0.5 mg (Gilenya; Novartis Pharma AG, Basel, Switzerland) in the USA as an oral therapy for relapsing forms of multiple sclerosis, long-term clinical experience with this therapy has been increasing. This review provides a summary of the cumulative dataset from clinical trials and their extensions, plus postmarketing studies that contribute to characterizing the efficacy and safety profile of fingolimod in patients with relapsing forms of multiple sclerosis. Data from the controlled, phase III, pivotal studies [FREEDOMS (FTY720 Research Evaluating Effects of Daily Oral therapy in Multiple Sclerosis), FREEDOMS II and TRANSFORMS (Trial Assessing Injectable Interferon versus FTY720 Oral in Relapsing-Remitting Multiple Sclerosis)] in relapsing-remitting multiple sclerosis have shown that fingolimod has a robust effect on clinical and magnetic resonance imaging outcomes. The respective study extensions show that effects on annualized relapse rates are sustained with continued fingolimod treatment. Consistent, significant reductions in magnetic resonance imaging lesion counts and brain volume loss have also been sustained with long-term treatment. The safety profile of fingolimod is also examined, particularly in light of its long-term use. A summary of the adverse events of interest that are associated with fingolimod treatment and associated label guidelines are also considered, which include cardiac effects following first-dose administration, infections, lymphopenia, macular edema and pregnancy. Historic hurdles to the prescription of fingolimod and how these challenges are being met are also discussed.

Fingolimod for multiple sclerosis and emerging indications: appropriate patient selection, safety precautions, and special considerations

Fingolimod (FTY720), an immunotherapeutic drug targeting the sphingosine-1-phosphate receptor, is a widely used medication for relapsing-remitting multiple sclerosis (MS). Apart from the pivotal Phase III trials demonstrating efficacy against placebo and interferon-β-1a once weekly, sufficient clinical data are now available to assess its real-world efficacy and safety profile. Approved indications of fingolimod differ between countries. This discrepancy, to some extent, reflects the intermediate position of fingolimod in the expanding lineup of MS medications. With individualization of therapy, appropriate patient selection gets more important. We discuss various scenarios for fingolimod use in relapsing-remitting MS and their pitfalls: as first-line therapy, as escalation therapy after failure of previous immunotherapies, and as de-escalation therapy following highly potent immunotherapies. Potential side effects such as bradycardia, infections, macular edema, teratogenicity, and progressive multifocal leukoencephalopathy as well as appropriate safety precautions are outlined. Disease reactivation has been described upon fingolimod cessation; therefore, patients should be closely monitored for MS activity for several months after stopping fingolimod. Finally, we discuss preclinical and clinical data indicating neuroprotective effects of fingolimod, which might open the way to future indications such as stroke, Alzheimer’s disease, and other neurodegenerative disorders.

The Direct Effects of Fingolimod in the Central Nervous System: Implications for Relapsing Multiple Sclerosis

Fingolimod, a structural analog of sphingosine derived from fungal metabolites, is a functional antagonist of the G-protein-coupled sphingosine 1-phosphate (S1P) receptors S1P(1,3,4,5). In the treatment of relapsing forms of multiple sclerosis (RMS), fingolimod acts by reversibly retaining central memory T cells and naïve T cells in lymph nodes, thereby reducing the recirculation of autoreactive lymphocytes to the central nervous system (CNS). Fingolimod also has differential effects on the trafficking and function of B-cell subtypes and natural killer (NK) cells in peripheral blood and the CNS. Fingolimod also crosses the blood-brain barrier (BBB) and accumulates in the CNS. Experimental evidence increasingly supports a direct action of fingolimod within the CNS on brain cells, providing protection against the neurodegenerative component of RMS. We review the direct influence of this compound on CNS pathogenesis in RMS, including the central effects of fingolimod in animal models of MS and on neural cell types that express S1P receptors, such as astrocytes, BBB endothelial cells, microglia, neurones, and oligodendrocytes, which are all involved in RMS pathology.

Maximum type I error rate inflation from sample size reassessment when investigators are blind to treatment labels

Consider a parallel group trial for the comparison of an experimental treatment to a control, where the second‐stage sample size may depend on the blinded primary endpoint data as well as on additional blinded data from a secondary endpoint. For the setting of normally distributed endpoints, we demonstrate that this may lead to an inflation of the type I error rate if the null hypothesis holds for the primary but not the secondary endpoint.

We derive upper bounds for the inflation of the type I error rate, both for trials that employ random allocation and for those that use block randomization. We illustrate the worst‐case sample size reassessment rule in a case study. For both randomization strategies, the maximum type I error rate increases with the effect size in the secondary endpoint and the correlation between endpoints. The maximum inflation increases with smaller block sizes if information on the block size is used in the reassessment rule. Based on our findings, we do not question the well‐established use of blinded sample size reassessment methods with nuisance parameter estimates computed from the blinded interim data of the primary endpoint. However, we demonstrate that the type I error rate control of these methods relies on the application of specific, binding, pre‐planned and fully algorithmic sample size reassessment rules and does not extend to general or unplanned sample size adjustments based on blinded data. © 2015 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

Optimizing the initial choice and timing of therapy in relapsing-remitting multiple sclerosis

With 12 available US Food and Drug Administration approved medications for the treatment of relapsing multiple sclerosis (MS), choosing an initial therapy is no longer a straightforward task. Each disease-modifying therapy (DMT) has a distinct risk-benefit profile and each patient is an individual. Therefore, the development of a simple algorithm to apply in selecting initial therapy is not feasible. Instead, the prescribing physician must consider many factors related to the treatments themselves, such as efficacy, safety, and tolerability, while also taking into account a particular patient's disease characteristics, personal preferences, comorbid illnesses and reproductive plans. The efficacy of each drug may be assessed through clinical trial data, although these data are limited by scarcity of direct comparisons among the different agents and lack of availability of biomarkers to predict an individual patient's response. Differences in safety profiles help to distinguish the various DMTs and influence selection of agent; both the known safety concerns, which can be addressed with risk mitigation and monitoring strategies, and the potential for yet undiscovered safety issues must be assessed, and an individual patient's comfort level with the risks and ability to comply with monitoring must be determined. Potential issues related to tolerability, which largely relate to matters of patient personal preference and lifestyle, should also be factored into the decision-making process. With regard to the timing of therapy initiation, it must be acknowledged that long-term benefits of early DMT have not yet been definitively demonstrated. Nonetheless, starting DMT early in the MS disease course has been shown to have a beneficial effect on relapse prevention, and appears to curtail the atrophy and neurodegenerative changes that are now known to begin at disease onset. Although under certain circumstances there are acceptable reasons for deferring treatment, it is generally recommended that DMT is initiated early in the disease course.

Infection risk in patients on multiple sclerosis therapeutics

The interface of multiple sclerosis (MS) and infection occurs on several levels. First, infectious disease has been postulated as a potential trigger, if not cause, of MS. Second, exacerbation of MS has been well-documented as a consequence of infection, and, lastly, infectious diseases have been recognized as a complication of the therapies currently employed in the treatment of MS. MS is a disease in which immune dysregulation is a key component. Examination of central nervous system (CNS) tissue of people affected by MS demonstrates immune cell infiltration, activation and inflammation. Therapies that alter the immune response have demonstrated efficacy in reducing relapse rates and evidence of brain inflammation on magnetic resonance imaging (MRI). Despite the altered immune response in MS, there is a lack of evidence that these patients are at increased risk of infectious disease in the absence of treatment or debility. Links between infections and disease-modifying therapies (DMTs) used in MS will be discussed in this review, as well as estimates of occurrence and ways to potentially minimize these risks. We address infection in MS in a comprehensive fashion, including (1) the impact of infections on relapse rates in patients with MS; (2) a review of available infection data from pivotal trials and postmarketing studies for the approved and experimental DMTs, including frequency, types and severity of infections; and (3) relevant risk minimization strategies, particularly as they pertain to progressive multifocal leukoencephalopathy (PML).

Overview and safety of fingolimod hydrochloride use in patients with multiple sclerosis

INTRODUCTION

Fingolimod (Gilenya®, FTY720) is an oral sphingosine-1-phosphate analogue that was approved by the FDA in 2010 for the treatment of relapsing forms of multiple sclerosis (MS). Fingolimod's mechanism of action is primarily related to lymphocyte sequestration in primary and secondary lymphoid tissues. Phase III trials demonstrated a reduction in annualized relapse rate and MRI progression in fingolimod-treated subjects compared with both placebo and IFN-β-treated subjects. Frequent adverse effects include fatigue, gastrointestinal disturbance, headache and upper respiratory tract infection. More serious, but rare, adverse events associated with fingolimod include atrioventricular block, symptomatic bradycardia, herpetic viral infections and macular edema.

AREAS COVERED

We discuss the mechanism of action, pharmacokinetics, clinical efficacy and safety profile of fingolimod in patients with relapsing MS.

EXPERT OPINION

Fingolimod is an effective treatment for relapsing MS and its oral route of administration may be preferred by some. Fingolimod is generally well tolerated but requires diligence in patient selection and monitoring. Additional information is needed regarding risk of infection, malignancy and rebound disease with long-term use of fingolimod.

Newly produced T and B lymphocytes and T-cell receptor repertoire diversity are reduced in peripheral blood of fingolimod-treated multiple sclerosis patients

BACKGROUND

Fingolimod inhibits lymphocyte egress from lymphoid tissues, thus altering the composition of the peripheral lymphocyte pool of multiple sclerosis patients.

OBJECTIVE

The objective of this paper is to evaluate whether fingolimod determines a decrease of newly produced T- and B-lymphocytes in the blood and a reduction in the T-cell receptor repertoire diversity that may affect immune surveillance.

METHODS

Blood samples were obtained from multiple sclerosis patients before fingolimod therapy initiation and then after six and 12 months. Newly produced T and B lymphocytes were measured by quantifying T-cell receptor excision circles and K-deleting recombination excision circles by real-time PCR, while recent thymic emigrants, naive CD8(+) lymphocytes, immature and naive B cells were determined by immune phenotyping. T-cell receptor repertoire was analyzed by complementarity determining region 3 spectratyping.

RESULTS

Newly produced T and B lymphocytes were significantly reduced in peripheral blood of fingolimod-treated patients. The decrease was particularly evident in the T-cell compartment. T-cell repertoire restrictions, already present before therapy, significantly increased after 12 months of treatment.

CONCLUSIONS

These results do not have direct clinical implications but they may be useful for further understanding the mode of action of this immunotherapy for multiple sclerosis patients.

Fingolimod for the treatment of neurological diseases-state of play and future perspectives

Sphingolipids are a fascinating class of signaling molecules derived from the membrane lipid sphingomyelin. They show abundant expression in the brain. Complex sphingolipids such as glycosphingolipids (gangliosides and cerebrosides) regulate vesicular transport and lysosomal degradation and their dysregulation can lead to storage diseases with a neurological phenotype. More recently, simple sphingolipids such ceramide, sphingosine and sphingosine 1-phosphate (S1P) were discovered to signal in response to many extracellular stimuli. Forming an intricate signaling network, the balance of these readily interchangeable mediators is decisive for cell fate under stressful conditions. The immunomodulator fingolimod is the prodrug of an S1P receptor agonist. Following receptor activation, the drug leads to downregulation of the S1P₁ receptor inducing functional antagonism. As the first drug to modulate the sphingolipid signaling pathway, it was marketed in 2010 for the treatment of multiple sclerosis (MS). At that time, immunomodulation was widely accepted as the key mechanism of fingolimod’s efficacy in MS. But given the excellent passage of this lipophilic compound into the brain and its massive brain accumulation as well as the abundant expression of S1P receptors on brain cells, it is conceivable that fingolimod also affects brain cells directly. Indeed, a seminal study showed that the protective effect of fingolimod in experimental autoimmune encephalitis (EAE), a murine MS model, is lost in mice lacking the S1P₁ receptor on astrocytes, arguing for a specific role of astrocytic S1P signaling in MS. In this review, we discuss the role of sphingolipid mediators and their metabolizing enzymes in neurologic diseases and putative therapeutic strategies arising thereof.