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

Novel triazine-tyrosine hybrids containing thiyazol or pyridine fragment as anti-multiple sclerosis agents: Design, synthesis, biological evaluation, and molecular docking study

In this study novel triazine-tyrosine hybrids containing thiazole or pyridine fragments were introduced as anti- Multiple Sclerosis agents. The compounds were designed according to the structure of the Sphingosine-1-phosphate receptor subtype 1 (S1P1) modulator, fingolimode. At first, docking studies was performed using crystal structures of S1P1 and Sphingosine-1-phosphate receptor subtype 3 (S1P3) to theoretically identify the selectivity of the compounds towards the S1P1 isoform. The docking results showed better binding energy (lower ΔGb) and therefore higher selectivity for S1P1 receptor than S1P3 receptor. Subsequently the designed compounds were synthesized according to proper chemical reactions and structurally analyzed with FTIR and NMR spectrophotometers. Considering the importance of the S1P1 receptor in release of lymphocytes and therefore inflammation produced in Multiple Sclerosis disease, the synthesized compounds were investigated to study lymphocyte reduction in an animal model. Compound (8e) with 2-mercaptobenzothiazole substitution at doses of 1 and 3 mg/kg showed significant reduction effect on the percentage of lymphocytes (68.80 %, 56.75 %) compared to the fingolimod (65.73 %, 20.66 %), as the positive control group.

Modern Advanced Therapies for Inflammatory Bowel Diseases: Practical Considerations and Positioning

The therapeutic armamentarium for management of inflammatory bowel diseases has expanded dramatically in the last 5 years, with the introduction of several medications with different mechanisms of action. These include the oral small molecule drugs Janus kinase inhibitors (including upadacitinib, approved for Crohn's disease and ulcerative colitis [UC], and tofacitinib, approved for UC) and sphingosphine 1-phosphate receptor modulators (ozanimod and etrasimod, both approved for UC), and biologic agents, such as selective interleukin-23 antagonists (risankizumab approved for Crohn's disease, and mirikizumab approved for UC). The efficacy and safety of these therapies vary. In this review, we discuss practical use of these newer advanced therapies focusing on real-world effectiveness and safety data, dosing and monitoring considerations, and special situations for their use, such as pregnancy, comorbid immune-mediated disease, use in hospitalized patients with acute severe UC, and in the perioperative setting. We also propose our approach to positioning these therapies in clinical practice, relying on careful integration of the medication's comparative effectiveness and safety in the context of an individual patient's risk of disease- and treatment-related complications and preferences.

Cryptococcosis Associated With Biologic Therapy: A Narrative Review

Cryptococcus is an opportunistic fungal pathogen that can cause disseminated infection with predominant central nervous system involvement in patients with compromised immunity. Biologics are increasingly used in the treatment of neoplasms and autoimmune/inflammatory conditions and the prevention of transplant rejection, which may affect human defense mechanisms against cryptococcosis. In this review, we comprehensively investigate the association between cryptococcosis and various biologics, highlighting their risks of infection, clinical manifestations, and clinical outcomes. Clinicians should remain vigilant for the risk of cryptococcosis in patients receiving biologics that affect the Th1/macrophage activation pathways, such as tumor necrosis factor α antagonists, Bruton tyrosine kinase inhibitors, fingolimod, JAK/STAT inhibitors (Janus kinase/signal transducer and activator of transcription), and monoclonal antibody against CD52. Other risk factors-such as age, underlying condition, and concurrent immunosuppressants, especially corticosteroids-should also be taken into account during risk stratification.

Icanbelimod (CBP-307), a next-generation Sphingosine-1-phosphate receptor modulator, in healthy men: pharmacokinetics, pharmacodynamics, safety, and tolerability in a randomized trial in Australia

Background

Icanbelimod (formerly CBP-307) is a next-generation S1PR modulator, targeting S1PR1. In this first-in-human study, icanbelimod was investigated in healthy men in Australia.

Methods

Participants were randomized 3:1, double-blind, to icanbelimod or placebo in four single-dose cohorts (0.1 mg, 0.25 mg, 0.5 mg [n=8 per cohort], 2.5 mg [n=4]) or for 28-days once-daily treatment in two cohorts (0.15 mg, 0.25 mg [n=8 per cohort]). Participants in the 0.25-mg cohort received 0.1 mg on Day 1. Treatments were administered orally after fasting; following one-week washout, icanbelimod was administered after breakfast in the 0.5-mg cohort.

Results

Icanbelimod exposure increased rapidly and dose-dependently with single and multiple dosing (Tmax 4-7 hours). Lymphocyte counts decreased rapidly after single (-11%, 0.1 mg; -40%, 0.25 mg; -71%, 0.5 mg; -77%, 2.5 mg) and multiple doses (-49%, 0.15 mg; -75%, 0.25 mg), and recovered quickly, 7 days after dosing. After single-dose 0.5 mg, although a high-fat breakfast versus fasting did not affect maximal decrease, lymphocyte counts tended to be lower after breakfast across most timepoints up to 72 hours. Twenty-eight participants (63.6%) experienced mainly mild treatment-emergent adverse events (TEAEs). After single-dose icanbelimod, the most common TEAEs were headache (28.6%, n=6) and dizziness (19.0%, n=4). Three participants experienced transient bradycardia, with one serious, following single-dose 2.5 mg icanbelimod. After multiple-dose icanbelimod, the most common TEAEs were headache (50.0%, n=6) and lymphopenia (41.7%, n=5), and two participants withdrew due to non-serious TEAEs. Up-titration attenuated heart rate reductions.

Conclusion

Icanbelimod was well-tolerated up to 0.5 mg and effectively reduced lymphocyte counts.

Clinical trial registration

ClinicalTrials.gov, identifier NCT02280434.b.

Risk of T2 lesions when discontinuing fingolimod: a nationwide predictive and comparative study

Fingolimod is a frequently used disease-modifying therapy in relapsing-remitting multiple sclerosis. However, case reports and small observational studies indicate a highly increased risk of disease reactivation after discontinuation. We aimed to investigate the risk of radiological disease reactivation in patients discontinuing fingolimod. We performed a nationwide cohort study in Denmark, including patients who discontinued fingolimod between January 2014 and January 2023. Eligibility was a diagnosis with relapsing-remitting multiple sclerosis and two MRIs performed respectively within 1 year before and after discontinuing fingolimod. The included patients were compared with those discontinuing dimethyl fumarate with the same eligibility criteria in an unadjusted and matched propensity score analysis. Matching was done on age, sex, Expanded Disability Status Scale, MRI data, cause for treatment discontinuation, treatment duration and relapse rate. The main outcome was the presence of new T2 lesions on the first MRI after treatment discontinuation. To identify high-risk patients among those discontinuing fingolimod, we made a predictive model assessing risk factors for obtaining new T2 lesions. Of 1324 patients discontinuing fingolimod in the study period, 752 were eligible for inclusion [mean age (standard deviation), years, 41 (10); 552 females (73%); median Expanded Disability Status Scale (Q1-Q3), 2.5 (2.0-3.5); mean disease duration (standard deviation), years, 12 (8)]. Of 2044 patients discontinuing dimethyl fumarate in the study period, 957 were eligible for inclusion, presenting similar baseline characteristics. Among patients discontinuing fingolimod, 127 (17%) had 1-2 new T2 lesions, and 124 (17%) had ≥3 new T2 lesions compared with 114 (12%) and 45 (5%), respectively, for those discontinuing dimethyl fumarate, corresponding to odds ratios (95% confidence interval) of 1.8 (1.3-2.3) and 4.4 (3.1-6.3). The predictive model, including 509 of the 752 patients discontinuing fingolimod, showed a highly increased risk of new T2 lesions among those with disease activity during fingolimod treatment and among females under 40 years. This nationwide study suggests that discontinuing fingolimod in some cases carries a risk of developing new T2 lesions, emphasizing the importance of clinical awareness. If feasible, clinicians should prioritize the prompt initiation of new disease-modifying therapies, particularly among young females.

A short washout period from fingolimod to anti-CD20 therapy is safe and decreases the risk of reactivation

The frequency of switches between Disease Modifying Therapies (DMTs) in Multiple Sclerosis (MS) has increased considerably over previous years. Between fingolimod and anti-CD20 therapies, a 1-month washout period is usually recommended. However, disease reactivations are frequent after fingolimod (Fg) cessation. Using a retrospective observational monocentric exposed/non-exposed cohort study, we investigated the efficacy and the safety of a shorter washout period (WP) between Fg and anti-CD20. We compared two groups: 25 patients with a short WP (<21 days) and 20 patients with a longer WP (>21 days). We observed no reactivation during WP in patients with a short WP against a relapse in 55% of patients in the longer group. Moreover, clinical and biological safety was excellent. Based on these findings, we recommend a shorter WP between fingolimod and anti-CD20 therapies in MS.

Serology results after COVID vaccine in multiple sclerosis patients treated with fingolimod

INTRODUCTION

While it is recommended that patients with multiple sclerosis (MS) be vaccinated against COVID-19, it is unknown what the vaccine response is in MS patients treated with fingolimod, an agent which modulates the humoral response. We aimed to characterize the immune response to the COVID-19 vaccine in MS patients treated with fingolimod and to explore which factors influenced response.

METHOD

We collected the following data from 59 MS patients treated with fingolimod and vaccinated against COVID-19: age, sex, duration of treatment, number of vaccine doses, date of last vaccination, type of vaccine, lymphocyte count, history of COVID-19, and serology to measure the vaccine response. We used Student's t-test and Chi² test to see whether there was a relationship between these variables and seropositivity. A multivariate logistic regression model was used to identify factors influencing the serology result. A multivariate linear regression model was used to identify factors influencing the antibody titer.

RESULTS

Twenty-eight participants (47%) developed a positive serology. Age (P<0.001) and the duration of treatment (P=0.002) were significantly related to seropositivity. Gender (P=0.73), number of vaccinations (P=0.78), lymphocyte count (P=0.46), and the time between the last vaccine dose and blood sampling (P=0.84) were not significant variables. Multivariate analysis using logistic regression (n=59) showed that age (P=0.003, RR = 2.28, 95%CI = 1.28, 4.07) and duration of treatment (P=0.04, RR=1.91, 95%CI=1.04, 3.50) were significantly and independently correlated with COVID serology. Multivariate linear regression analysis of the antibody titer (n=59) found the duration of treatment to be significant (P = 0.015), but not age (P = 0.53). After removing three outliers, age (P = 0.005, RR=6.82, 95%CI=1.66, 27.98) and duration of treatment (P = 0.008, RR=5.12, 95%CI=1.24, 21.03) were significantly correlated with the antibody titer.

CONCLUSION

COVID-19 seropositivity was present in 47% of our sample of 59 MS patients on fingolimod. A strong relationship was found between antibody development, age, and duration of treatment, as well as between antibody titer and age and duration of treatment.

Prediction of relapse activity when switching to cladribine for multiple sclerosis

BACKGROUND

Patients with relapsing-remitting multiple sclerosis commonly switch between disease-modifying therapies (DMTs). Identifying predictors of relapse when switching could improve outcomes.

OBJECTIVE

To determine predictors of relapse hazard when switching to cladribine.

METHODS

Data of patients who switched to cladribine, grouped by prior disease-modifying therapy (pDMT; interferon-β/glatiramer acetate, dimethyl fumarate, teriflunomide, fingolimod or natalizumab (NTZ)), were extracted from the MSBase Registry. Predictors of relapse hazard during the treatment gap and the first year of cladribine therapy were determined.

RESULTS

Of 513 patients, 22 relapsed during the treatment gap, and 38 within 1 year of starting cladribine. Relapse in the year before pDMT cessation predicted treatment gap relapse hazard (hazard ratio (HR) = 2.43, 95% confidence interval (CI)  = 1.03-5.71). After multivariable adjustment, relapse hazard on cladribine was predicted by relapse before pDMT cessation (HR = 2.00, 95% CI = 1.01-4.02), treatment gap relapse (HR = 6.18, 95% confidence interval (CI) = 2.65-14.41), switch from NTZ (HR compared to injectable therapies 4.08, 95% CI = 1.35-12.33) and age at cladribine start (HR = 0.96, 95% CI = 0.91-0.99).

CONCLUSION

Relapse during or prior to the treatment gap, and younger age, are of prognostic relevance in the year after switching to cladribine. Switching from NTZ is also independently associated with greater relapse hazard.

A Literature Review of Ozanimod Therapy in Inflammatory Bowel Disease: From Concept to Practical Application

Inflammatory bowel disease (IBD), namely Ulcerative Colitis (UC) and Crohn's Disease (CD), is believed to be due to a dysregulation of the innate immune response. The complexity of the immune cascade offers both a challenge and an opportunity to researchers seeking out new treatments for IBD, as various points along the inflammatory pathways can be targeted for interruption. Sphinogosine-1-phosphate (S1P) is a phospholipid molecule with wide ranging biological effects caused by binding five known S1P receptor subtypes. Ozanimod is a small molecule drug that selectively targets S1P receptors 1 and 5 which play a crucial role in lymphocyte trafficking. In clinical trials for both UC and CD, it has been shown to induce a reversible lymphopenia which correlates with response to therapy. Reported adverse events include infection, anemia, and elevated liver enzymes. Rare instances of bradycardia, heart block, and macular edema were also reported. As a newly available therapy approved for UC patients, we aim to summarize ozanimod's novel mechanism of action, pre-clinical and clinical trial results, and to give context to this newly available drug that gastroenterologists may utilize in their treatment algorithm.

Screening for severe drug-drug interactions in patients with multiple sclerosis: A comparison of three drug interaction databases

Background: Patients with multiple sclerosis (MS) often undergo complex treatment regimens, resulting in an increased risk of polypharmacy and potential drug-drug interactions (pDDIs). Drug interaction databases are useful for identifying pDDIs to support safer medication use. Objective: To compare three different screening tools regarding the detection and classification of pDDIs in a cohort of MS patients. Furthermore, we aimed at ascertaining sociodemographic and clinical factors that are associated with the occurrence of severe pDDIs. Methods: The databases Stockley's, Drugs.com and MediQ were used to identify pDDIs by screening the medication schedules of 627 patients. We determined the overlap of the identified pDDIs and the level of agreement in pDDI severity ratings between the three databases. Logistic regression analyses were conducted to determine patient risk factors of having a severe pDDI. Results: The most different pDDIs were identified using MediQ (n = 1,161), followed by Drugs.com (n = 923) and Stockley's (n = 706). The proportion of pDDIs classified as severe was much higher for Stockley's (37.4%) than for Drugs.com (14.4%) and MediQ (0.9%). Overall, 1,684 different pDDIs were identified by at least one database, of which 318 pDDIs (18.9%) were detected with all three databases. Only 55 pDDIs (3.3%) have been reported with the same severity level across all databases. A total of 336 pDDIs were classified as severe (271 pDDIs by one database, 59 by two databases and 6 by three databases). Stockley's and Drugs.com revealed 47 and 23 severe pDDIs, respectively, that were not included in the other databases. At least one severe pDDI was found for 35.2% of the patients. The most common severe pDDI was the combination of acetylsalicylic acid with enoxaparin, and citalopram was the drug most frequently involved in different severe pDDIs. The strongest predictors of having a severe pDDI were a greater number of drugs taken, an older age, living alone, a higher number of comorbidities and a lower educational level. Conclusions: The information on pDDIs are heterogeneous between the databases examined. More than one resource should be used in clinical practice to evaluate pDDIs. Regular medication reviews and exchange of information between treating physicians can help avoid severe pDDIs.

Dose-dependent reduction of lymphocyte count and heart rate after multiple administration of LC51-0255, a novel sphingosine-1-phosphate receptor 1 modulator, in healthy subjects

Aim: Sphingosine-1-phosphate receptor mediates the egress of lymphocytes from lymphoid organs, and its inhibition results in a decreased number of circulating lymphocytes. The aim of the current study was to investigate the safety and pharmacodynamic and pharmacokinetic characteristics of a novel sphingosine-1-phosphate receptor modulator, LC51-0255.

Methods: A phase 1 randomized, double-blind, placebo-controlled, multiple dosing, dose-escalation study was conducted on healthy Korean male subjects.

Results: After single and daily administration of LC51-0255 for 21 days, a dose-dependent decrease in lymphocyte count and heart rate was observed through 0.25–2 mg dose range of LC51-0255. The mean elimination half-life of LC51-0255 was 76–95 h. LC51-0255 was accumulated with a mean accumulation ratio of 5.17–6.64. During the study, LC51-0255 was generally well tolerated. The most common treatment-emergent adverse event was bradycardia. No clinically significant event of arrhythmia, including AV block, was observed. No clinically significant difference in blood pressure was observed between the dose groups. In other safety assessments, no clinically significant abnormalities were observed, except for bradycardia.

Conclusion: Daily administration of LC51-0255 in the range of 0.25–2 mg resulted in a dose-dependent reduction of lymphocyte counts and heart rate. LC51-0255 is generally safe and well tolerated in healthy volunteers.

Prediction of multiple sclerosis outcomes when switching to ocrelizumab

BACKGROUND

Increasingly, people with relapsing-remitting multiple sclerosis (RRMS) are switched to highly effective disease-modifying therapies (DMTs) such as ocrelizumab.

OBJECTIVE

To determine predictors of relapse and disability progression when switching from another DMT to ocrelizumab.

METHODS

Patients with RRMS who switched to ocrelizumab were identified from the MSBase Registry and grouped by prior disease-modifying therapy (pDMT; interferon-β/glatiramer acetate, dimethyl fumarate, teriflunomide, fingolimod or natalizumab) and washout duration (<1 month, 1-2 months or 2-6 months). Survival analyses including multivariable Cox proportional hazard regression models were used to identify predictors of on-ocrelizumab relapse within 1 year, and 6-month confirmed disability progression (CDP).

RESULTS

After adjustment, relapse hazard when switching from fingolimod was greater than other pDMTs, but only in the first 3 months of ocrelizumab therapy (hazard ratio (HR) = 3.98, 95% confidence interval (CI) = 1.57-11.11, p = 0.004). The adjusted hazard for CDP was significantly higher with longer washout (2-6 m compared to <1 m: HR = 9.57, 95% CI = 1.92-47.64, p = 0.006).

CONCLUSION

The risk of disability worsening during switch to ocrelizumab is reduced by short treatment gaps. Patients who cease fingolimod are at heightened relapse risk in the first 3 months on ocrelizumab. Prospective evaluation of strategies such as washout reduction may help optimise this switch.

Neurological update: treatment escalation in multiple sclerosis patients refractory to fingolimod-potentials and risks of subsequent highly active agents

A critical issue in the management of relapsing MS (RMS) is the discontinuation of disease-modifying treatments (DMT) due to lack of efficacy, intolerability or impending risks. With new therapeutic agents introduced into the treatment of RMS, immediate- and long-term consequences of sequential drug use, as well as the effect of the sequence in which the drugs are given, are unclear but may affect efficacy, adverse events, and long-term immunocompetence. In the absence of clinical studies specifically addressing these concerns, observations from clinical practice are of particular value in guiding current management algorithms. Prompted by a study published by Ferraro et al. in this journal, we set out to provide an overview of the published real-world evidence on the effectiveness and safety of switching from fingolimod to another DMT in patients with active RMS. Seventeen publications reporting relevant information were identified. The literature suggests that immune cell depletion induced by alemtuzumab or ocrelizumab is associated with an increased risk of relapse and worsening disability in patients switching from fingolimod compared to patients switching from other therapeutic agents. However, the evidence reported for natalizumab and cladribine is inconclusive. While shortening of the washout period may limit early disease reactivation after fingolimod discontinuation, there is no strong evidence that the duration of the washout period or the absolute lymphocyte count at baseline are predictors of attenuated long-term efficacy. Further real-world studies are required to better understand outcomes among patients who are under-represented in controlled trials.

Cryptococcal Meningitis Reported With Fingolimod Treatment: Case Series

BACKGROUND AND OBJECTIVES

To describe the characteristics of patients with MS reporting cryptococcal meningitis (CM) while treated with fingolimod.

METHODS

The Novartis safety database was searched for cases with CM between January 26, 2006, and February 28, 2020. The reporting rate of CM was estimated based on the case reports received and exposure to fingolimod in the postmarketing setting during the relevant period.

RESULTS

A total of 60 case reports of CM were identified, mostly from the United States. The median age was 48 years, and 51.8% were women. Most of the patients had recovered or were recovering at the time of final report. A fatal outcome occurred in 13 cases. During the study period, the rate of CM in patients with MS receiving fingolimod was estimated to be 8 per 100,000 patient-years (95% CI: 6.0; 10.0). The incidence of CM seemed to increase with duration of treatment; however, this relationship remains uncertain due to wide CIs and missing data.

DISCUSSION

The causal relationship between fingolimod treatment and CM is not yet fully understood. The CM mortality rate in fingolimod-treated patients is similar to that reported in HIV-negative patients. Vigilance for signs and symptoms of CM in patients receiving fingolimod, particularly the new onset of headaches and altered mental status, is essential. Early diagnosis and treatment are critical to reducing CM-associated mortality.

Immune response to the third COVID-19 vaccine dose is related to lymphocyte count in multiple sclerosis patients treated with fingolimod

Background

The majority of multiple sclerosis [MS] patients treated with fingolimod fail to develop a protective level of IgG humoral and adaptive cellular immune responses following full BNT162b2 SARS-CoV-2 vaccination.

Objective

To compare the efficacy of the third COVID-19 vaccine dose in vaccine non-responders fingolimod-treated MS patients.

Study design

This is a prospective 3-month, single-center, randomized clinical trial.

Methods

Twenty relapsing MS patients who had been on fingolimod therapy ≥ 12 months and failed to develop humoral IgG immune response to 2-dose Pfizer BNT162b2 COVID-19 vaccination were randomized into two groups: fingolimod-continuation group and fingolimod-discontinuation group. Humoral and memory cellular immune responses were assessed within 1 and 3 months following the third Pfizer BNT162b2 vaccine dose and compared between the groups.

Results

A higher rate of patients in the fingolimod-discontinuation group [n = 8/10] compared to fingolimod-continuation group [n = 2/10] developed positive SARS-COV-2 IgG. Median IgG titer 1 month following the third dose was 202.3 BAU/ml vs. 26.4 BAU/ml, respectively, p = 0.022. The development of IgG humoral response correlated with absolute lymphocyte count. Specific SARS-COV-2 memory B cell and T cell immune responses were not detected in both groups, either at 1 month or 3 months following the third COVID-19 vaccine dose.

Conclusions

Short period of fingolimod treatment discontinuation was associated with the development of humoral protection but not with adaptive cellular immunity.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00415-022-11030-0.

The risk of infections for multiple sclerosis and neuromyelitis optica spectrum disorder disease-modifying treatments: Eighth European Committee for Treatment and Research in Multiple Sclerosis Focused Workshop Review. April 2021

Over the recent years, the treatment of multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) has evolved very rapidly and a large number of disease-modifying treatments (DMTs) are now available. However, most DMTs are associated with adverse events, the most frequent of which being infections. Consideration of all DMT-associated risks facilitates development of risk mitigation strategies. An international focused workshop with expert-led discussions was sponsored by the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) and was held in April 2021 to review our current knowledge about the risk of infections associated with the use of DMTs for people with MS and NMOSD and corresponding risk mitigation strategies. The workshop addressed DMT-associated infections in specific populations, such as children and pregnant women with MS, or people with MS who have other comorbidities or live in regions with an exceptionally high infection burden. Finally, we reviewed the topic of DMT-associated infectious risks in the context of the current SARS-CoV-2 pandemic. Herein, we summarize available evidence and identify gaps in knowledge which justify further research.

Lymphocyte Counts and Multiple Sclerosis Therapeutics: Between Mechanisms of Action and Treatment-Limiting Side Effects

Although the detailed pathogenesis of multiple sclerosis (MS) is not completely understood, a broad range of disease-modifying therapies (DMTs) are available. A common side effect of nearly every MS therapeutic agent is lymphopenia, which can be both beneficial and, in some cases, treatment-limiting. A sound knowledge of the underlying mechanism of action of the selected agent is required in order to understand treatment-associated changes in white blood cell counts, as well as monitoring consequences. This review is a comprehensive summary of the currently available DMTs with regard to their effects on lymphocyte count. In the first part, we describe important general information about the role of lymphocytes in the course of MS and the essentials of lymphopenic states. In the second part, we introduce the different DMTs according to their underlying mechanism of action, summarizing recommendations for lymphocyte monitoring and definitions of lymphocyte thresholds for different therapeutic regimens.

Secondary Immunodeficiency and Risk of Infection Following Immune Therapies in Neurology

Secondary immunodeficiencies (SIDs) are acquired conditions that may occur as sequelae of immune therapy. In recent years a number of disease-modifying therapies (DMTs) has been approved for multiple sclerosis and related disorders such as neuromyelitis optica spectrum disorders, some of which are frequently also used in- or off-label to treat conditions such as chronic inflammatory demyelinating polyneuropathy (CIDP), myasthenia gravis, myositis, and encephalitis. In this review, we focus on currently available immune therapeutics in neurology to explore their specific modes of action that might contribute to SID, with particular emphasis on their potential to induce secondary antibody deficiency. Considering evidence from clinical trials as well as long-term observational studies related to the patients' immune status and risks of severe infections, we delineate long-term anti-CD20 therapy, with the greatest data availability for rituximab, as a major risk factor for the development of SID, particularly through secondary antibody deficiency. Alemtuzumab and cladribine have relevant effects on circulating B-cell counts; however, evidence for SID mediated by antibody deficiency appears limited and urgently warrants further systematic evaluation. To date, there has been no evidence suggesting that treatment with fingolimod, dimethyl fumarate, or natalizumab leads to antibody deficiency. Risk factors predisposing to development of SID include duration of therapy, increasing age, and pre-existing low immunoglobulin (Ig) levels. Prevention strategies of SID comprise awareness of risk factors, individualized treatment protocols, and vaccination concepts. Immune supplementation employing Ig replacement therapy might reduce morbidity and mortality associated with SIDs in neurological conditions. In light of the broad range of existing and emerging therapies, the potential for SID warrants urgent consideration among neurologists and other healthcare professionals.

Lessons from S1P receptor targeting in multiple sclerosis

Sphingosine 1-phosphate (S1P) is a potent bioactive sphingolipid binding to specific G protein-coupled receptors expressed in several organs. The relevance of S1P-S1P receptor axis in the pathophysiology of immune and nervous systems has encouraged the development of S1P receptor modulators for the treatment of neurological, autoimmune and/or inflammatory disorders. Currently, four S1P receptor modulators are approved drugs for multiple sclerosis (MS), an inflammatory disorder of the central nervous system. As main pharmacologic effect, these treatments induce lymphopenia due to the loss of responsiveness to S1P gradients guiding lymphocyte egress from lymphoid organs into the bloodstream. Recent data point to immunological effects of the S1P modulators beyond the inhibition of lymphocyte trafficking. Further, these drugs may cross the blood-brain barrier and directly target CNS resident cells expressing S1P receptors. Here we review the role of S1P signalling in neuroimmunology at the light of the evidences generated from the study of the mechanism of action of S1P receptor modulators in MS and integrate this information with findings derived from neuroinflammatory animal models and in vitro observations. These insights can direct the application of therapeutic approaches targeting S1P receptors in other disease areas.

Risk of multiple sclerosis relapses when switching from fingolimod to cell-depleting agents: the role of washout duration

BACKGROUND

Fingolimod (FTY) induces sequestration of lymphocytes in secondary lymphoid organs and the average lymphocyte recovery following discontinuation takes 1-2 months. It has been hypothesized that the therapeutic effects of subsequent cell-depleting agents may be compromised if initiated before lymphocyte recovery has occurred.

OBJECTIVE

To assess the risk of relapses following FTY discontinuation and the initiation of a B/T cell-depleting agent in relation to washout duration using data from the Italian MS Register.

METHODS

The risk of relapses was assessed in relation to different washout durations (< 6, 6-11, 12-17 and > / = 18 weeks) in patients starting alemtuzumab, rituximab, ocrelizumab or cladribine following FTY discontinuation.

RESULTS

We included 329 patients in the analysis (226F, 103 M; mean age 41 ± 10 years). During the cell-depleting treatment, the incidence rate ratio for a relapse was significantly greater in patients with a washout period of 12-17 and > / = 18 weeks compared to the reference period (< 6 weeks). The risk of a relapse was significantly influenced by the occurrence of relapses during FTY treatment and by washout length, with hazard ratios markedly increasing with the washout duration.

CONCLUSION

The risk of relapses increases with the washout duration when switching from FTY to lymphocyte-depleting agents.

Effects of disease-modifying therapy on peripheral leukocytes in patients with multiple sclerosis

Modern disease-modifying therapies (DMTs) in multiple sclerosis (MS) have variable modes of action and selectively suppress or modulate the immune system. In this review, we summarize the predicted and intended as well as unwanted adverse effects on leukocytes in peripheral blood as a result of treatment with DMTs for MS. We link changes in laboratory tests to the possible therapeutic risks that include secondary autoimmunity, infections, and impaired response to vaccinations. Profound knowledge of the intended effects on leukocyte counts, in particular lymphocytes, explained by the mode of action, and adverse effects which may require additional laboratory and clinical vigilance or even drug discontinuation, is needed when prescribing DMTs to treat patients with MS.

What happens after fingolimod discontinuation? A multicentre real-life experience

OBJECTIVE

To analyse the course of multiple sclerosis (MS) after fingolimod withdrawal in a multicentre cohort.

METHODS

Patients who discontinued fingolimod were included. Relapses, Expanded Disability Status Scale (EDSS), and new/gadolinium-enhancing lesions on magnetic resonance imaging (MRI) were assessed during the last year on fingolimod, and in the year after discontinuation. Wilcoxon test was used to analyse the difference in EDSS and relapses between the two periods, and to compare lymphocyte counts at discontinuation and 3 months later. Demographic and clinical variables were evaluated using univariable and multivariable logistic regression analyses.

RESULTS

Patients were 230 (females 66.1%; mean age 38 years; median EDSS 3). Fingolimod was discontinued due to inefficacy in 57%, and 87.4% started another treatment. Relapse was observed in 33% of the patients in the year after discontinuation. Severe reactivation was observed in 15%. During the first 6 months after discontinuation, new/enhancing lesions were seen in 62/116 patients. Higher age at the fingolimod discontinuation was found to be associated with a lower probability of inflammatory activity (p = 0.001) and severe reactivation (p = 0.007) during the year after discontinuation. Lower lymphocyte count was a risk factor for clinical, radiological, and severe activity (p = 0.02, p = 0.002, p = 0.01, respectively).

CONCLUSIONS

The main reason for the discontinuation of fingolimod was inefficacy. One-third of the patients had a relapse during the year after discontinuation, 15% experienced a severe reactivation, and approximately 50% of patients with available MRI scan had new/enhancing lesions. The risk factors for disease activity after discontinuation were low lymphocyte count and younger age.

Ozanimod for the treatment of relapsing forms of multiple sclerosis

Multiple sclerosis (MS) is an inflammatory disease that causes chronic neurological disability in young adults. Modulation of sphingosine 1-phosphate (S1P) receptors, a group of receptors that, among other things, regulate egression of lymphocytes from lymph nodes, has proven to be effective in treating relapsing MS. Fingolimod, the first oral S1P receptor modulator, has demonstrated potent efficacy and tolerability, but can cause undesirable side effects due to its interaction with a wide range of S1P receptor subtypes. This review will focus on ozanimod, a more selective S1P receptor modulator, which has recently received approval for relapsing MS. We summarize ozanimod's mechanism of action, and efficacy and safety from clinical trials that demonstrate its utility as another treatment option for relapsing MS.

Sphingosine 1-Phosphate Receptor Modulators for Multiple Sclerosis

Fingolimod (Gilenya) received regulatory approval from the US FDA in 2010 as the first-in-class sphingosine 1-phosphate (S1P) receptor (S1PR) modulator and was the first oral disease-modifying therapy (DMT) used for the treatment of the relapsing forms of multiple sclerosis (MS). Development of this new class of therapeutic compounds has continued to be a pharmacological goal of high interest in clinical trials for treatment of various autoimmune disorders, including MS. S1P is a physiologic signaling molecule that acts as a ligand for a group of cell surface receptors. S1PRs are expressed on various body tissues and regulate diverse physiological and pathological cellular responses involved in innate and adaptive immune, cardiovascular, and neurological functions. Subtype 1 of the S1PR (S1PR₁) is expressed on the cell surface of lymphocytes, which are well known for their major role in MS pathogenesis and play an important regulatory role in the egress of lymphocytes from lymphoid organs to the lymphatic circulation. Thus, S1PR₁-directed pharmacological interventions aim to modulate its role in immune cell trafficking through sequestration of autoreactive lymphocytes in the lymphoid organs to reduce their recirculation and subsequent infiltration into the central nervous system. Indeed, receptor subtype selectivity for S1PR₁ is theoretically favored to minimize safety concerns related to interaction with other S1PR subtypes. Improved understanding of fingolimod's mechanism of action has provided strategies for the development of the more selective second-generation S1PR modulators. This selectivity serves to reduce the most important safety concern regarding cardiac-related side effects, such as bradycardia, which requires prolonged first-dose monitoring. It has led to the generation of smaller molecules with shorter half-lives, improved onset of action with no requirement for phosphorylation for activation, and preserved efficacy. The shorter half-lives of the second-generation agents allow for more rapid reversal of their pharmacological effects following treatment discontinuation. This may be beneficial in addressing further treatment-related complications in case of adverse events, managing serious or opportunistic infections such as progressive multifocal leukoencephalopathy, and eliminating the drug in pregnancies. In March 2019, a breakthrough in MS treatment was achieved with the FDA approval for the second S1PR modulator, siponimod (Mayzent), for both active secondary progressive MS and relapsing-remitting MS. This was the first oral DMT specifically approved for active forms of secondary progressive MS. Furthermore, ozanimod received FDA approval in March 2020 for treatment of relapsing forms of MS, followed by subsequent approvals from Health Canada and the European Commission. Other second-generation selective S1PR modulators that have been tested for MS, with statistically significant data from phase II and phase III clinical studies, include ponesimod (ACT-128800), ceralifimod (ONO-4641), and amiselimod (MT-1303). This review covers the available data about the mechanisms of action, pharmacodynamics and kinetics, efficacy, safety, and tolerability of the various S1PR modulators for patients with relapsing-remitting, secondary progressive, and, for fingolimod, primary progressive MS.

Recurrence of disease activity after fingolimod discontinuation in older patients previously stable on treatment

BACKGROUND

Discontinuing fingolimod (FTY) in older patients is a growing concern with little evidence supporting the decision to pursue treatment and reasonable doubt for disease reactivation after withdrawal.

OBJECTIVE

To estimate the incidence of recurrence of disease activity (RDA) and rebound after FTY withdrawal in patients older than 50 years.

METHODS

Retrospective analysis of all MS patients in our clinic who discontinued FTY after at least 6 months of treatment, according to disease activity on FTY and age at discontinuation. RDA was defined as the occurrence of either clinical and/or MRI activity in the 6 months after FTY withdrawal and rebound when the levels of disease activity surpassed pretreatment activity.

RESULTS

From the 128 patients who discontinued FTY since 2011, up to 35.2% of patients experienced evidence of disease activity and 12.5% had a rebound. The incidence of both RDA and rebound was not different among individuals who had persistent disease activity on FTY to those who stopped FTY for other reasons than inefficacy (RDA: 25.5% vs 20.5%, p = 0.353 rebound: 14.5% vs 11%, p = 0.596). Negative predictive factors for RDA were younger age at disease onset (p = 0.036), highly active disease at baseline (p = 0.003) and previous treatment with NTZ (p = 0.013). Older age at FTY discontinuation did not reduce the risk of RDA in patients previously stable on treatment (OR 0.972, 95% CI 0.871-1.085, p = 0.613), although the incidence of RDA/rebound was half less in the older patients (36.5% in the <50 vs 19% in the ≥50 year-old, p = 0.174) and none of the patients over 60 experienced RDA.

CONCLUSION

Although there is a tendency for a lower risk of disease reactivation in the older patients, the incidence of RDA, and even rebound, is not negligible between the age of 50 and 60 years, even in patients with previously stable MS on FTY.

Fingolimod in multiple sclerosis: profile of use in habitual practice

OBJECTIVES

Fingolimod is the first oral drug indicated in monotherapy as a modifier of the course of very active relapsing-remitting multiple sclerosis (RRMS). The safety profile of fingolimod is well established in clinical trials and post-marketing studies. Our objective was to study the profile of fingolimod use in our health area.

METHODS

A retrospective, observational, descriptive study was performed on the use of fingolimod in adult patients diagnosed with RRMS between January 2015 and February 2017 or until suspension of treatment in a reference hospital in north-western Spain.

RESULTS

A total of 55 patients were included with a mean±SD time of treatment with fingolimod of 26±14.6 months (range 2-53). Thirteen patients permanently discontinued the treatment (10 due to outbreaks/disease progression and 3 due to adverse effects). No statistically significant differences were found between the percentage of patients who discontinued fingolimod and who had received only one previous treatment and those who had received two or more treatments. No cases of symptomatic bradycardia were reported.

CONCLUSIONS

Fingolimod is a safe treatment for patients with multiple sclerosis.

Amiselimod, a sphingosine 1-phosphate receptor-1 modulator, for systemic lupus erythematosus: A multicenter, open-label exploratory study

OBJECTIVE

To evaluate the safety, pharmacokinetics, pharmacodynamics, and exploratory efficacy of amiselimod, an oral selective sphingosine 1-phosphate receptor-1 modulator, in patients with systemic lupus erythematosus (SLE).

METHODS

A multicenter, open-label phase Ib trial was conducted in Japan. Patients in Part 1 and Part 2-B received 0.2 mg amiselimod while those in Part 2-A received 0.4 mg amiselimod for 24 weeks.

RESULTS

Seventeen subjects received 0.2 or 0.4 mg amiselimod. Amiselimod and amiselimod-P plasma concentrations increased dose-dependently. Peripheral blood lymphocyte count decreased in all patients after amiselimod treatment, with no clear dose response. There were no serious/severe adverse events (AEs) or clinically meaningful cardiac effects. Five subjects were withdrawn from amiselimod treatment following a decrease in lymphocyte count to <200/μl. Anti-double stranded-DNA antibody decreased from baseline to Week 24/end of treatment (EOT), with those in 2 subjects (22.2%) decreasing to within the normal range. Total SLE disease activity index 2000 score decreased by ≥4 at EOT in 7 of 17 subjects.

CONCLUSIONS

Amiselimod was generally well tolerated. While no serious AEs or infectious AEs led to discontinuation, low lymphocyte counts of <200/μl were observed as a laboratory abnormality. Our findings suggest the potential efficacy of amiselimod for patients with SLE.Trial registration: ClinicalTrials.gov identifier: NCT02307643.

Pre-clinical and Clinical Implications of "Inside-Out" vs. "Outside-In" Paradigms in Multiple Sclerosis Etiopathogenesis

Multiple Sclerosis (MS) is an immune-mediated neurological disorder, characterized by central nervous system (CNS) inflammation, oligodendrocyte loss, demyelination, and axonal degeneration. Although autoimmunity, inflammatory demyelination and neurodegeneration underlie MS, the initiating event has yet to be clarified. Effective disease modifying therapies need to both regulate the immune system and promote restoration of neuronal function, including remyelination. The challenge in developing an effective long-lived therapy for MS requires that three disease-associated targets be addressed: (1) self-tolerance must be re-established to specifically inhibit the underlying myelin-directed autoimmune pathogenic mechanisms; (2) neurons must be protected from inflammatory injury and degeneration; (3) myelin repair must be engendered by stimulating oligodendrocyte progenitors to remyelinate CNS neuronal axons. The combined use of chronic and relapsing remitting experimental autoimmune encephalomyelitis (C-EAE, R-EAE) (“outside-in”) as well as progressive diphtheria toxin A chain (DTA) and cuprizone autoimmune encephalitis (CAE) (“inside-out”) mouse models allow for the investigation and specific targeting of all three of these MS-associated disease parameters. The “outside-in” EAE models initiated by myelin-specific autoreactive CD4⁺ T cells allow for the evaluation of both myelin-specific tolerance in the absence or presence of neuroprotective and/or remyelinating agents. The “inside-out” mouse models of secondary inflammatory demyelination are triggered by toxin-induced oligodendrocyte loss or subtle myelin damage, which allows evaluation of novel therapeutics that could promote remyelination and neuroprotection in the CNS. Overall, utilizing these complementary pre-clinical MS models will open new avenues for developing therapeutic interventions, tackling MS from the “outside-in” and/or “inside-out”.

Delay from treatment start to full effect of immunotherapies for multiple sclerosis

In multiple sclerosis, treatment start or switch is prompted by evidence of disease activity. Whilst immunomodulatory therapies reduce disease activity, the time required to attain maximal effect is unclear. In this study we aimed to develop a method that allows identification of the time to manifest fully and clinically the effect of multiple sclerosis treatments (‘therapeutic lag’) on clinical disease activity represented by relapses and progression-of-disability events. Data from two multiple sclerosis registries, MSBase (multinational) and OFSEP (French), were used. Patients diagnosed with multiple sclerosis, minimum 1-year exposure to treatment, minimum 3-year pretreatment follow-up and yearly review were included in the analysis. For analysis of disability progression, all events in the subsequent 5-year period were included. Density curves, representing incidence of relapses and 6-month confirmed progression events, were separately constructed for each sufficiently represented therapy. Monte Carlo simulations were performed to identify the first local minimum of the first derivative after treatment start; this point represented the point of stabilization of treatment effect, after the maximum treatment effect was observed. The method was developed in a discovery cohort (MSBase), and externally validated in a separate, non-overlapping cohort (OFSEP). A merged MSBase-OFSEP cohort was used for all subsequent analyses. Annualized relapse rates were compared in the time before treatment start and after the stabilization of treatment effect following commencement of each therapy. We identified 11 180 eligible treatment epochs for analysis of relapses and 4088 treatment epochs for disability progression. External validation was performed in four therapies, with no significant difference in the bootstrapped mean differences in therapeutic lag duration between registries. The duration of therapeutic lag for relapses was calculated for 10 therapies and ranged between 12 and 30 weeks. The duration of therapeutic lag for disability progression was calculated for seven therapies and ranged between 30 and 70 weeks. Significant differences in the pre- versus post-treatment annualized relapse rate were present for all therapies apart from intramuscular interferon beta-1a. In conclusion we have developed, and externally validated, a method to objectively quantify the duration of therapeutic lag on relapses and disability progression in different therapies in patients more than 3 years from multiple sclerosis onset. Objectively defined periods of expected therapeutic lag allows insights into the evaluation of treatment response in randomized clinical trials and may guide clinical decision-making in patients who experience early on-treatment disease activity. This method will subsequently be applied in studies that evaluate the effect of patient and disease characteristics on therapeutic lag.

Lymphocyte recovery after fingolimod discontinuation in patients with MS

Objective

To investigate the dynamics of immune cells recovery after treatment discontinuation of fingolimod in real-life clinical practice, we analyzed the course of lymphocyte reconstitution and its potential influencing factors in patients with multiple sclerosis (MS).

Methods

We analyzed leukocyte, lymphocyte, and granulocyte counts of 58 patients at 3, 6, and 12 months after fingolimod cessation and the following parameters as potential risk factors for a prolonged lymphopenia up to 12 months: age; sex; Expanded Disability Status Scale, and disease duration at the time of fingolimod start; type and number of previous immunomodulatory treatments; fingolimod treatment duration; lymphocyte count at baseline before fingolimod, at fingolimod stop, and at the time of therapy switch; time interval between fingolimod cessation and new treatment initiation; type of the follow-up immunomodulatory treatment; and corticosteroid administration after fingolimod cessation.

Results

All patients showed a drop of the lymphocyte count under fingolimod with no relevant leukopenia or neutropenia. One year after discontinuation, still 22% of the patients were lymphopenic and 54% of them did not reach 80% of the baseline lymphocyte value. Low lymphocyte counts before fingolimod start, under fingolimod, and at therapy switch, successive treatment with rituximab, and pretreatment with mitoxantrone were significantly associated with a prolonged immune cell recovery.

Conclusions

Prolonged lymphopenia after fingolimod cessation exists in a subgroup of patients with MS and should be considered in clinical practice, particularly when changing treatment regimens.

Long-term drug treatment in multiple sclerosis: safety success and concerns

INTRODUCTION

The portfolio of multiple sclerosis (MS) disease modifying treatments (DMTs) has significantly expanded over the past two decades. Given the lifelong use of MS pharmacotherapy, understanding their long-term safety profiles is essential in determining suitable and personalized treatment.

AREAS COVERED

In this narrative review, we summarize the short-, mid-, and long-term safety profile of currently available MS DMTs categories. In addition to the initial trial findings, safety outcomes derived from long-term extension studies (≥5-20 years) and safety-based prescription programs have been reviewed. In order to better understand the risk-benefit ratio for each particular DMT group, a short description of the DMT-based efficacy outcomes has been included.

EXPERT OPINION

Long-term extension trials, large observational studies and real-world databases allow detection of rare and potentially serious adverse events. Two-year-long trials are unable to fully capture the positive and negative effects of immune system modulation and reconstitution. DMT-based monitoring programs can provide greater insights regarding safe use of MS medications in different patient populations and clinical settings. During the process of shared DMT decision, both MS care providers and their patients should be aware of an ever-expanding number of drug-based adverse events and their influence on the risk-benefit analysis.

Managing Disease-Modifying Therapies and Breakthrough Activity in Multiple Sclerosis Patients During the COVID-19 Pandemic: Toward an Optimized Approach

The emergence of the novel coronavirus disease 2019 (COVID-19) pandemic has become a major public health challenge of global concern since December 2019, when the virus was recognized in Wuhan, the capital city of Hubei province in China and epicenter of the COVID-19 epidemic. Given the novelty of COVID-19 and the lack of specific anti-virus therapies, the current management is essentially supportive. There is an absence of consensus on guidelines or treatment strategies for complex disorders such as multiple sclerosis (MS), in which the risk of infections is higher than in the general population. This is due to the overall impairment of the immune system typical of autoimmune diseases, in addition to accumulation of disabilities, and the iatrogenic effect generated by corticosteroids and the recommended disease-modifying therapies (DMTs). DMTs have different modes of action, but all modulate and interfere with the patient's immune response, thereby raising concerns about adverse effects, such as an increased susceptibility to infections. In this review, we analyze the evidence for use of DMTs during the current critical period and ratify an algorithmic approach for management to optimize care between keeping DMTs, with their infection hazards, or coming off them, with the risk of disease activation. We also provide an algorithmic approach to the management of breakthrough activity during the COVID-19 pandemic.

Tumefactive multiple sclerosis in association with fingolimod initiation and discontinuation

BACKGROUND

Tumefactive multiple sclerosis (TMS) is a rare multiple sclerosis (MS) form that usually manifests as the initial presentation or in the early stages of MS.

OBJECTIVE

The aim of this study is to evaluate reports of TMS associated with fingolimod use.

METHODS

The Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) database and the medical literature were searched for cases of TMS occurring during or after fingolimod treatment.

RESULTS

We identified 29 TMS cases, 19 following fingolimod initiation and 10 following fingolimod discontinuation. In these cases, a TMS diagnosis occurred at a median of 7 years after MS diagnosis, and a median of 7 and 3 months following initiation and discontinuation of fingolimod, respectively. Twenty-two cases were assessed as possible and seven as probable from a causal association perspective. A much larger crude number of TMS reports was observed for fingolimod compared to other disease-modifying therapies.

CONCLUSION

TMS should be considered when a severe or atypical MS relapse occurs shortly after fingolimod initiation or discontinuation, and should prompt imaging evaluation and appropriate treatment initiation. Prescribers' awareness of the association between TMS and fingolimod may avoid unnecessary diagnostic procedures. In light of our findings, fingolimod (Gilenya) prescribing information was amended to include TMS in the Warnings and Precautions section.

Temporal profile of lymphocyte counts and relationship with infections with fingolimod therapy in paediatric patients with multiple sclerosis: Results from the PARADIGMS study

BACKGROUND

Reduction in absolute lymphocyte count (ALC) is expected with fingolimod treatment.

OBJECTIVE

To evaluate the effect of fingolimod 0.5 mg versus intramuscular interferon β-1a (30 μg) on ALC and its relationship with infections in paediatric-onset multiple sclerosis (POMS) up to 4 years.

METHODS

We assessed ALC at baseline, monthly till 3 months, and every 3 months (core phase) and with variable periodicity (extension phase) of Phase 3 PARADIGMS study (N = 215). Incidence rates (IRs) of infection-related adverse events (^infAEs)/100 patient-years were analysed by on-study nadir ALC.

RESULTS

With fingolimod, ALC rapidly reduced to 29.9%-34.4% of baseline values within 2 weeks and remained stable thereafter; no relevant changes observed with interferon. IRs of ^infAEs were 67.6 with fingolimod and 61.8 with interferon; IR ratios with respect to interferon, overall: 1.09, by nadir ALC 0.2-0.4 × 10⁹/L: 1.13 and >0.4 × 10⁹/L: 0.91. Three patients had a single episode of ALC <0.2 × 10⁹/L (core phase). No opportunistic infections were observed and infection risk did not increase during the extension phase.

CONCLUSION

In paediatric patients, the overall incidence of infections was comparable between fingolimod and interferon. No association was observed between nadir ALC and infections in POMS, although sample size may have been too small to rule an association.

Management of central nervous system demyelinating diseases during the coronavirus disease 2019 pandemic: a practical approach

BACKGROUND

The novel coronavirus disease 2019 (COVID-19) pandemic poses a potential threat to patients with autoimmune disorders, including multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD). Such patients are usually treated with immunomodulatory or immunosuppressive agents, which may tamper with the organism's normal response to infections. Currently, no consensus has been reached on how to manage MS and NMOSD patients during the pandemic.

OBJECTIVE

To discuss strategies to manage those patients.

METHODS

We focus on how to 1) reduce COVID-19 infection risk, such as social distancing, telemedicine, and wider interval between laboratory testing/imaging; 2) manage relapses, such as avoiding treatment of mild relapse and using oral steroids; 3) manage disease-modifying therapies, such as preference for drugs associated with lower infection risk (interferons, glatiramer, teriflunomide, and natalizumab) and extended-interval dosing of natalizumab, when safe; 4) individualize the chosen MS induction-therapy (anti-CD20 monoclonal antibodies, alemtuzumab, and cladribine); 5) manage NMOSD preventive therapies, including initial therapy selection and current treatment maintenance; 6) manage MS/NMOSD patients infected with COVID-19.

CONCLUSIONS

In the future, real-world case series of MS/NMOSD patients infected with COVID-19 will help us define the best management strategies. For the time being, we rely on expert experience and guidance.

Anti-inflammatory Efficacy of Combined Natural Alkaloid Berberine and S1PR Modulator Fingolimod at Low Doses in Ulcerative Colitis Preclinical Models

The natural alkaloid berberine is being studied as a drug candidate for the treatment of ulcerative colitis (UC). Fingolimod is an immunomodulator approved for the treatment of multiple sclerosis. Whether fingolimod use can be extended to UC and how it interacts with berberine remain unclear. In the present study, the anti-inflammatory efficacies of berberine, fingolimod, and a combination of half-doses of them was examined in mice with dextran sulfate sodium-induced colitis. In mice with subchronic colitis, 14-day oral administration of fingolimod had greater efficacy than berberine in ameliorating the disease clinical severity and colon shortening. However, in mice with chronic colitis, 30-day oral administration of berberine was more effective than fingolimod except on splenic swelling. Notably, the combination of half-doses of each drug was equally effective as the superior single drugs for two models and resulted in reduced splenic swelling in the chronic colitis model. The inhibition of cytokine expression and STAT3 activation, as well as binding to the sphingosine 1-phosphate receptor by both drugs, contributed to the combination efficacy. Our findings suggest that fingolimod in combination with berberine at reduced doses represents a novel therapy for UC that attains satisfactory efficacy with reduced potentials for adverse effects.

Immune Reconstitution Therapy or Continuous Immunosuppression for the Management of Active Relapsing-Remitting Multiple Sclerosis Patients? A Narrative Review

The majority of disease-modifying drugs (DMDs) available for the management of active relapsing-remitting multiple sclerosis (RMS) depend on continuous drug intake for maintained efficacy, with escalation to a more active drug when an unacceptable level of disease activity returns. Among continuously applied regimens, interferons and glatiramer acetate act as immunomodulators, while dimethyl fumarate, fingolimod, ocrelizumab, natalizumab and teriflunomide are associated with continuous immunosuppression. By contrast, immune reconstitution therapy (IRT) provides efficacy that outlasts a short course of treatment. Autologous hemopoietic stem cell transplantation is perhaps the classic example of IRT, but this invasive and intensive therapy has challenging side-effects. A short treatment course of a pharmacologic agent hypothesized to act as an IRT, such as Cladribine Tablets 3.5 mg/kg or alemtuzumab, can provide long-term suppression of MS disease activity, without need for continuous treatment (the anti-CD20 mechanism of ocrelizumab has the potential to act as an IRT, but is administered continuously, at 6-monthly intervals). Cladribine Tablets 3.5 mg/kg shows some selectivity in targeting adaptive immunity with a lesser effect on innate immunity. The introduction of IRT-like disease-modifying drugs (DMDs) challenges the traditional maintenance/escalation mode of treatment and raises new questions about how disease activity is measured. In this review, we consider a modern classification of DMDs for MS and its implications for the care of patients in the IRT era.

[New directions of immunocorrection in multiple sclerosis]

Multiple sclerosis is a central nervous system disease with autoimmune and neurodegenerative mechanisms of development. This disease can lead to severe disability and neurological defects. Although its etiology and pathogenesis remain unclear, research data show that multiple sclerosis is a multifactorial disease, the development of which depends on environmental factors, as well as a genetic predisposition. The impact of these factors lead to the death of neural cells, accompanied by demyelination of nerves and neuronal dysfunction. Therapy of multiple sclerosis is based on the use of anti-inflammatory and immunomodulating substances, however, there are certain disadvantages associated with the constant use of these drugs and a possible change in dosage over time. This review discusses the pathogenesis of multiple sclerosis and the role of various subpopulations of immune cells in the development of diseases, as well as existing approaches to therapy. It is noted that immunoreconstitution therapy has advantages over immunomodulation and immunosuppression maintenance therapy for some patients. Thus, short courses of therapy provide more adequate treatment for patients and lower risks of adverse events associated with chronic immunosuppression. The review also discusses the data of clinical studies on the immunoreconstitution therapy drugs, such as alemtuzumab, ocrelizumab and cladribine. It is noted that nowadays the exact mechanisms underlying this type of therapy remain unclear. In this regard, further studies are needed to explain the therapeutic effects. It is assumed that patients with a high risk of multiple sclerosis progression are the optimal group of patients for the early use of selective immunoreconstitution therapy. Thus, immunoreconstitution therapy may be the treatment of choice for many patients with highle active multiple sclerosis.

Cryptococcus neoformans var grubii meningoencephalitis in a patient on fingolimod for relapsing-remitting multiple sclerosis: Case report and review of published cases

INTRODUCTION

Fingolimod, a sphingosine-1-phosphate modulator used in the treatment of relapsing-remitting multiple sclerosis, has been associated with several cases of cryptococcosis.

CASE REPORT

We present a case of Cryptococcal meningoencephalitis attributable to Cryptococcus neoformans var. grubii, in a 58-year-old bird-keeper from Australia, after 7 years of fingolimod therapy. We discuss this in the context of previously reported cases, our understanding of fingolimod immune modulation, and known Cryptococcus pathobiology.

CONCLUSION

We suggest consideration of harm minimisation behaviours in patients requiring fingolimod, particularly in those with profound CD4 lymphopenia. Furthermore, we echo the call for improved post-marketing surveillance systems to determine the epidemiology of atypical infections with novel immunomodulatory treatments.

Lymphopenia and DMTs for relapsing forms of MS: Considerations for the treating neurologist

Purpose of review

To provide neurologists with an update on the proposed mechanisms of action (MOAs) of disease-modifying therapies (DMTs) for the treatment of relapsing MS, and their effect on peripheral blood leukocytes, in order to inform treatment decisions.

Recent findings

DMTs have vastly differing MOAs, including effects on peripheral blood leukocyte counts, particularly lymphocytes. The clinical implications of changes in lymphocyte counts need to be understood in the context of the underlying MOAs of each respective DMT, with treatment tailored to individual patient needs.

Summary

DMTs can alter lymphocyte counts, subsets, activation, and distribution, and thus can influence immune surveillance. Serial monitoring of total leukocytes and absolute lymphocyte counts (ALCs) is advisable in patients receiving DMTs. ALCs should be interpreted regarding expected immunologic changes and individual patient characteristics. Any decision to switch DMTs should consider these factors, along with drug efficacy, safety, and effect on quality of life.

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.