An observational study of alemtuzumab following fingolimod for multiple sclerosis

Recurring disease activity in relapsing remitting multiple sclerosis: The multicenter RDA-RMS study

BACKGROUND

This study investigates the gap in understanding the dynamics of recurring disease activity (RDA) in RRMS patients after fingolimod (FGL) treatment discontinuation. The aim is to investigate RDA in RRMS patients after stopping FGL, aiming to improve management and comprehension of disease progression post-treatment.

METHODS

In this multicenter, retrospective study, data from 172 of 944 RRMS patients aged 18-55, across nine centers in Turkey, who discontinued FGL treatment, were analyzed. The collected data included EDSS scores, annualized relapse rates (ARR), lymphocyte counts, and MRI findings, with follow-up assessments conducted at 6 months, 1 year, and up to 2 years.

RESULTS

RDA was observed in 31.9 % of patients, with incidences of rebound and reactivation at 20.3 % and 11.6 %, respectively. Factors like younger age, longer treatment duration, lower lymphocyte counts, and higher lesion burden increased RDA risk. Notably, 52.9 % of pregnant patients experienced RDA (16.4 % of the overall RDA group), with rebound occurring in six and reactivation in three. Patients with RDA had longer medication-free intervals and increased ARR. Discontinuation reasons varied, with disease progression linked to a lower RDA risk.

CONCLUSION

Findings highlight the necessity for personalized management and vigilant monitoring after FGL discontinuation in RRMS patients, offering critical insights into RDA risk factors, and the complex interplay between treatment cessation, pregnancy, and disease progression.

Case report: tumefactive demyelinating lesions after the second cycle of alemtuzumab in multiple sclerosis; immune cell profile and biomarkers

Objective

We present a case of multiple tumefactive demyelinating lesions (TDLs) emerging 24 months after the second cycle of alemtuzumab treatment.

Methods

A woman with relapsing-remitting multiple sclerosis (MS) discontinued fingolimod treatment due to gestational desire, which resulted in a severe disease exacerbation. Alemtuzumab was initiated, accompanied by regular clinical, radiological, and immunological monitoring.

Results

She relapsed prior to the second cycle, exhibiting 12 T1Gd+ lesions, and peripheral blood showed an increase in B-cells and a decrease in T-cells. At 24 months following the second cycle, she developed cognitive impairment and multiple T1Gd+ lesions, including TDLs, were evident on the brain MRI. We found not only an increase in B-cells but also in Th1 central memory cells. Th1/Th17 cells increased 3 months before the detection of TDLs.

Conclusions

TDLs can appear 24 months after the second cycle of alemtuzumab treatment in MS. The increase in Th1/Th17 cells could be a candidate biomarker for TDLs in alemtuzumab-treated MS patients.

Real-World Effectiveness of Cladribine for Patients with Multiple Sclerosis: A Sicilian Multicentric Experience (Rewind Study)

BACKGROUND

Cladribine tablets are a highly effective option for the treatment of relapsingremitting multiple sclerosis (RRMS).

OBJECTIVE

The study aims to evaluate the effectiveness of cladribine in a real-world setting.

METHODS

This prospective real-world study consecutively screened all RRMS patients from seven different MS centers in Sicily (Italy) who completed the 2-year treatment course of cladribine tablets in the period between 11th March 2019 and 31st October 2021. Data about Expanded Disability Status Scale (EDSS), relapses, previous treatments, adverse events (AEs) and magnetic resonance imaging (MRI) were collected. Patients who were previously treated with other DMTs were further stratified into moderately active treatment (MAT) and highly active treatment (HAT) patients.

RESULTS

A total of 217 patients (70% women, with a mean age of 38.4 ± 11.3 years) were enrolled. Fifty patients (23.0%) were naïve to treatment and 167 (77%) switched from other disease modifying therapies. After the second year of treatment, about 80% were EDSS progression free, 88% remained relapse-free at T24, and 48% of patients were MRI activity-free. Kaplan Meier analyses showed significant differences between MT and HAT in terms of time to first clinical relapse (HR: 2.43, IC 1.02- 5.76; p = 0.04), time to the first new T1-gadolinium enhancing lesion (HR: 3.43, IC 1.35-8.70; p = 0.009) and time to MRI worsening (HR: 2.42, IC 1.15-5.09; p = 0.02).

CONCLUSION

This study confirmed that cladribine is an effective treatment for MS, particularly in naïve patients and those who have switched from MATs.

Multiple faces of multiple sclerosis in the era of highly efficient treatment modalities: Lymphopenia and switching treatment options challenges daily practice

The expanded treatment landscape in relapsing-remitting multiple sclerosis (MS) has resulted in highly effective treatment options and complexity in managing disease- or drug-related events during disease progression. Proper decision-making requires thorough knowledge of the immunobiology of MS itself and an understanding of the main principles behind the mechanisms that lead to secondary autoimmunity affecting organs other than the central nervous system as well as opportunistic infections. The immune system is highly adapted to both environmental and disease-modifying agents. Immune reconstitution following cell depletion or cell entrapment therapies eliminates pathogenic aspects of the disease but can also lead to distorted immune responses with harmful effects. Atypical relapses occur with second-line treatments or after their discontinuation and require appropriate clinical decisions. Lymphopenia is a result of the mechanism of action of many drugs used to treat MS. However, persistent lymphopenia and cell-specific lymphopenia could result in disease exacerbation, secondary autoimmunity, or the emergence of opportunistic infections. Clinicians treating patients with MS should be aware of the multiple faces of MS under novel, efficient treatment modalities and understand the intricate brain-immune cell interactions in the context of an altered immune system. MS relapses and disease progression still occur despite the current treatment modalities and are mediated either by failure to control effector mechanisms inherent to MS pathophysiology or by new drug-related mechanisms. The multiple faces of MS due to the highly adapted immune system of patients impose the need for appropriate switching therapies that safeguard disease remission and further clinical improvement.

A safety review of current monoclonal antibodies used to treat multiple sclerosis

INTRODUCTION

Multiple sclerosis (MS) is an autoimmune disease affecting the central nervous system. Monoclonal antibodies (mAbs) have shown efficacy in reducing MS relapse rates, disease progression, and brain lesion activity.

AREAS COVERED

This article reviews the literature on the use of mAbs for the treatment of MS, including their mechanisms of action, clinical trial data, safety profiles, and long-term outcomes. The review focuses on the three main categories of mAbs used in MS: alemtuzumab, natalizumab, and anti-CD20 drugs. A literature search was conducted using relevant keywords and guidelines and reports from regulatory agencies were reviewed. The search covered studies published from inception to 31 December 202231 December 2022. The article also discusses the potential risks and benefits of these therapies, including their effects on infection rates, malignancies, and vaccination efficacy.

EXPERT OPINION

Monoclonal antibodies have revolutionized the treatment of MS, but safety concerns must be considered, particularly with regards to infection rates, malignancy risk, and vaccination efficacy. Clinicians must weigh the potential benefits and risks of mAbs on an individual patient basis, taking into account factors such as age, disease severity, and comorbidities. Ongoing monitoring and surveillance are essential to ensure the long-term safety and effectiveness of monoclonal antibody therapies in MS.

Previous disease-modifying treatments influence T lymphocyte kinetics in people with multiple sclerosis switching to ocrelizumab

BACKGROUND

Recently, concern has been raised about the influence of the previous disease-modifying treatments (DMTs) on the clinical efficacy of ocrelizumab (OCR). We aimed to evaluate whether the previous DMT affects the lymphocyte subset kinetics in people with Multiple Sclerosis (MS) switching to OCR.

METHODS

This is a multicenter, retrospective, real-world study on consecutive MS patients who started or switched to OCR. We grouped them by prior DMT in: (i) naïve-to-treatment (NTT), (ii) switching from fingolimod (SF) and (iii) switching from natalizumab (SN). Differences in absolute lymphocyte count and lymphocyte subset count changes, considering the period from baseline to 6 months, over all the three groups were assessed with an inverse-probability-weighted regression adjustment model.

RESULTS

Mean T CD4+ cell count reduction from baseline to the six-month follow-up was more pronounced in the SN group compared to the NTT (p = 0,026). Further, patients in the SF group experienced a less pronounced CD4 T cell number decrease than both NTT and SN groups (p = 0,04 and p < 0,001, respectively). Patients in the SF group experienced an increase in CD8 T cell absolute number, whereas those in the NTT and SN groups experienced a significant decrease (p = 0,015 and p < 0,001, respectively). Patients experiencing early inflammatory activity showed a lower CD8+ cell count at baseline than stable patients (p = 0,02).

CONCLUSIONS

Previous DMTs influence the lymphocyte kinetics in people with MS switching to OCR. Reassessment of these findings over a larger population may help optimize the switch.

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.

Consensus statement on the use of alemtuzumab in daily clinical practice in Spain

INTRODUCTION

Alemtuzumab is a highly effective drug approved by the European Medicines Agency as a disease-modifying drug for the treatment of relapsing-remitting multiple sclerosis.

OBJECTIVE

A consensus document was drafted on the management of alemtuzumab in routine clinical practice in Spain.

DEVELOPMENT

A group of multiple sclerosis specialists reviewed articles addressing treatment with alemtuzumab in patients with multiple sclerosis and published before December 2017. The included studies assessed the drug's efficacy, effectiveness, and safety; screening for infections and vaccination; and administration and monitoring aspects. The initial proposed recommendations were developed by a coordinating group and based on the available evidence and their clinical experience. The consensus process was carried out in 2 stages, with the initial threshold percentage for group agreement established at 80%. The final document with all the recommendations agreed by the working group was submitted for external review and the comments received were considered by the coordinating group.

CONCLUSION

The present document is intended to be used as a tool for optimising the management of alemtuzumab in routine clinical practice.

Impact of previous disease-modifying treatment on safety and efficacy in patients with MS treated with AHSCT

BACKGROUND

Autologous haematopoietic stem cell transplantation (AHSCT) is a highly effective treatment for multiple sclerosis (MS). The impact of previous long-lasting disease-modifying treatments (DMT) for safety and efficacy of AHSCT is unknown.

OBJECTIVE

To explore whether previous DMTs with long-lasting effects on the immune system (anti-CD20 therapy, alemtuzumab and cladribine) affect treatment-related complications, long-term outcome and risk of new MS disease activity in patients treated with AHSCT.

METHODS

Retrospective observational study of 104 relapsing remitting patients with MS treated by AHSCT in Sweden and Norway from 2011 to 2021, grouped according to the last DMT used ≤6 months prior to AHSCT. The primary outcomes were early AHSCT-related complications (mortality, neutropenic fever and hospitalisation length), long-term complications (secondary autoimmunity) and proportion of patients with No Evidence of Disease Activity (NEDA-3 status): no new relapses, no MRI activity and no disease progression during the follow-up.

RESULTS

The mean follow-up time was 39.5 months (range 1-95). Neutropenic fever was a common AHSCT-related complication affecting 69 (66%) patients. There was no treatment-related mortality. During the follow-up period, 20 patients (19%) were diagnosed with autoimmunity. Occurrence of neutropenic fever, hospitalisation length or secondary autoimmunity did not vary dependent on the last DMT used prior to AHSCT. A total of 84 patients (81%) achieved NEDA-3 status, including all patients (100%) using rituximab, alemtuzumab or cladribine before AHSCT.

CONCLUSION

This study provides level 4 evidence that AHSCT in patients previously treated with alemtuzumab, cladribine or rituximab is safe and efficacious.

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.

Therapy Switches in Fingolimod-Treated Patients with Multiple Sclerosis: Long-Term Experience from the German MS Registry

INTRODUCTIONS

Therapy switches in patients with multiple sclerosis (MS) receiving treatment with fingolimod occur frequently in clinical practice but are not well represented in real-world data. The aim of this study was to identify and characterize treatment switches and reveal sociodemographic/clinical changes over time in fingolimod-treated people with MS (PwMS).

METHODS

Data on 2536 fingolimod-treated PwMS extracted from the German MS Registry during different time periods were analyzed (2010-2019).

RESULTS

Overall, 28.3% of PwMS were treatment-naïve before fingolimod initiation. Interferon beta (30.7%) was the most common pre-fingolimod treatment. Ocrelizumab (19.8%) was the most frequent subsequent treatment in the 944 patients on fingolimod who switched. Between 2010 and 2019, median disease duration at fingolimod initiation decreased from 8.5 to 7.1 years (p < 0.001), and patients taking fingolimod for ≥ 1 year after treatment initiation decreased from 89.6 to 80.5% (p < 0.001). Females (p < 0.001) and young patients (p = 0.003) showed a shorter time on fingolimod. The most frequent reason for switching was disease activity (relapse/MRI) despite treatment. The annualized relapse rate increased from 0.37 in patients on fingolimod to 0.47 after treatment cessation, decreasing to 0.19 after treatment with a subsequent disease-modifying drug (DMD) was initiated.

CONCLUSION

Treatment switches from fingolimod to subsequent DMDs currently occur after shorter treatment durations than 10 years ago, possibly due to the growing treatment spectrum. Planning adequate washout periods is essential and should be done on an individualized basis.

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.

Factors associated with fingolimod rebound: A single center real-life experience

Background It is still controversial whether the relapse experienced after discontinuation of fingolimod treatment is a rebound. Increasing cases of rebound have been reported in the literature. The rate of fingolimod rebound in patients after fingolimod cessation is reported between 5% and 52%. The present study aims to determine the rate of rebound after discontinuation of fingolimod treatment and the factors affecting the rebound. Methods This retrospective cohort study consists of adult MS patients who have been admitted to the Hacettepe University Hospital Neurology MS Center outpatient clinic between 2012 and 2020. Results During the study period, 642 patients received fingolimod and 23.1% discontinued the fingolimod treatment. Thirteen of 126 patients had a rebound (10.3%) after fingolimod discontinuation. The patients in the rebound group were significantly younger and washout period were significantly longer than those in the non-rebound group. After discontinuation of fingolimod treatment, the EDSS score of the rebound group was significantly higher than the non-rebound group, while Annualized Relapse Rates were similar. Conclusion Younger age, longer washout time, and previous treatment preferences may increase the occurrence probability of rebound. It is recommended that patients should be closely monitored after fingolimod discontinuation and appropriate disease-modifying therapy should be initiated as soon as possible.

A real-world study of alemtuzumab in a cohort of Italian patients

Background and purpose

Real‐world data on alemtuzumab are limited and do not provide evidence of its effectiveness after various disease‐modifying therapies (DMTs). Our aim was to provide real‐world data on the impact of clinical variables and previous DMTs on clinical response to alemtuzumab.

Methods

Sixteen Italian multiple sclerosis centers retrospectively included patients who started alemtuzumab from January 2015 to December 2018, and recorded demographics, previous therapies, washout duration, relapses, Expanded Disability Status Scale (EDSS) score, and magnetic resonance imaging data. Negative binomial regression models were used to assess the effect of factors on annualized relapse (ARR) after alemtuzumab initiation.

Results

We studied 322 patients (mean age 36.8 years, median EDSS score 3, median follow‐up 1.94 years). Previous treatments were: fingolimod (106), natalizumab (80), first‐line oral agents (56), first‐line injectables (interferon/glatiramer acetate; 30), and other drugs (15). Thirty‐five patients were treatment‐naïve. The pre‐alemtuzumab ARR was 0.99 and decreased to 0.13 during alemtuzumab treatment (p < 0.001). The number of previous‐year relapses was associated with alemtuzumab ARR (adjusted risk ratio [RR] 1.38, p = 0.009). Progression‐free survival was 94.5% after 1 year, and 89.2% after 2 years of alemtuzumab treatment. EDSS score improvement occurred in 13.5% after 1 year, and 20.6% after 2 years. Re‐baselining patients after 6 months of alemtuzumab treatment, led to no evidence of disease activity status in 71.6% after 1 year and 58.9% after 2 years.

Conclusions

Alemtuzumab decreases ARR independent of previous therapy, including patients with disease activity during natalizumab treatment. Overall, 90% of patients showed no disease progression, and 20% an improvement after 2 years of alemtuzumab.

Impact of previous disease-modifying treatment on effectiveness and safety outcomes, among patients with multiple sclerosis treated with alemtuzumab

OBJECTIVES

Alemtuzumab is effective in patients with active multiple sclerosis but has a complex safety profile, including the development of secondary autoimmunity. Most of patients enrolled in randomised clinical trials with alemtuzumab were either treatment naïve or pretreated with injectable substances. Other previous disease-modifying treatments (DMTs) were not used in the study cohorts, and therefore, associated risks might yet remain unidentified.

METHODS

We retrospectively evaluated a prospective dual-centre alemtuzumab cohort of 170 patients. We examined the baseline characteristics as well as safety and effectiveness outcomes, including the time to first relapse, the time to 3 months confirmed disability worsening and the time to secondary autoimmunity.

RESULTS

The regression analysis showed that, among all previously used DMTs, the pretreatment with fingolimod (n=33 HRs for the time to first relapse (HR 5.420, 95% CI 2.520 to 11.660; p<0.001)) and for the time to worsening of disability (HR 7.676, 95% CI 2.870 to 20.534; p<0.001). Additionally, patients pretreated with fingolimod were more likely to experience spinal relapses (55% vs 10% among previously naïve patients; p<0.001) and had an increased risk of secondary autoimmunity (HR 5.875, 95% CI 2.126 to 16.27; p<0.001).

CONCLUSION

In the real-world setting, we demonstrated suboptimal disease control and increased risk of secondary autoimmunity following alemtuzumab, among patients previously treated with fingolimod. These data can provide guidance for improving MS therapeutic management.

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.

How to switch disease-modifying treatments in multiple sclerosis: Guidelines from the French Multiple Sclerosis Society (SFSEP)

BACKGROUND

Today, there are no recommendations on switching disease-modifying treatments (DMTs) in multiple sclerosis (MS).

OBJECTIVES

To establish guidelines on switching DMTs MS.

METHODS

A Steering Committee composed of seven MS experts from the French Group for Recommendations in Multiple Sclerosis (France4MS) defined 15 proposals. These proposals were then submitted to a Rating Group, composed of 48 French MS experts, for evaluation. The proposals were classified as 'appropriate', 'inappropriate' or 'uncertain'.

RESULTS

Switching from a first-line therapy to another first-line therapy or a second-line therapy could be done without a washout period. Switching from a second-line therapy to a first-line therapy could be done without a washout period with fingolimod or natalizumab, after 3 months with ocrelizumab or mitoxantrone, and, if disease activity occurs with alemtuzumab or cladribine. The switch from a second-line therapy to another second-line therapy could be done after a washout period of 1 month with fingolimod or natalizumab, after 3 months with ocrelizumab, after 6 months with mitoxantrone, and, if disease activity occurs, with alemtuzumab or cladribine.

CONCLUSION

This expert consensus approach provides physicians with some guidelines on optimizing the benefit/risk ratio when switching DMTs in patients with MS.

Switch from sequestering to anti-CD20 depleting treatment: disease activity outcomes during wash-out and in the first 6 months of ocrelizumab therapy

OBJECTIVES

Switching between treatments is an opportunity for patients with multiple sclerosis (MS) to ameliorate disease control or safety. The aim of this study was to investigate the impact of switching from fingolimod (FTY) or natalizumab (NTZ) to ocrelizumab (OCR) on disease activity.

METHODS

We retrospectively enrolled 165 patients treated with OCR from 11 MS centres. We assessed the association of demographic and clinical characteristics on relapse rate (RR) and activity on magnetic resonance imaging (MRI) during wash-out and after 6 months of treatment with OCR through univariable and multivariable negative binomial regression models.

RESULTS

We registered a total of 35 relapses during the wash-out period. Previous treatment with FTY, relapses in the previous year, and relapsing-remitting course were associated with higher RR. In the first 6 months of OCR, 12 patients had clinical or MRI disease activity. Higher Expanded Disability Status Scale (EDSS) and higher lymphocyte count at OCR start were associated with a reduced probability of relapse.

DISCUSSION AND CONCLUSION

This study confirms that withdrawal from sequestering agents as FTY increases the risk of relapses in the wash-out period. Nevertheless, starting OCR before achieving complete immune reconstitution could limit its effectiveness in the first 6 months probably because trapped lymphocytes escape the CD20-mediated depletion.

Immune phenotyping study revealing caveats regarding a switch from fingolimod to cladribine

BACKGROUND

Recent data support a key role of B cells in the pathogenesis of multiple sclerosis. Due to the pronounced effect of cladribine on memory B cells, we initiated an immune phenotyping study, which included monitoring of memory B cells of patients newly assigned to this treatment option. A patient with ongoing disease activity in the first year of cladribine after a long-standing fingolimod treatment caught our attention.

OBJECTIVE

To report about differences in the immune phenotype of the case compared to patients without disease activity and to discuss possible causes for the deviations as caveats regarding treatment sequelae.

METHODS

Clinical data and immune phenotyping data collected at baseline (before treatment) and after three, six and ten/twelve months after cladribine initiation were compared between our case and six patients with a stable disease course (controls).

RESULTS

Both, the case and controls showed similar reductions of memory B cells in response to cladribine. The case however, showed an accelerated repopulation dynamic of naïve B cells with an almost 3-fold hyperrepopulation compared to baseline levels, and lower pre-treatment levels of CD4+ and CD8+ T cells and memory B cells compared to controls.

CONCLUSION

We propose a prolonged pre-treatment with fingolimod as possible cause for the lack of response to cladribine. Autoreactive cells sequestrated within lymph nodes may have evaded cladribine depletion on top of a delay of recirculating regulatory T cells. In addition, we want to raise awareness of the importance of monitoring T and B cells for bridging the current lack of evidence regarding sequencing therapies in the real life setting.

Newly approved agents for relapsing remitting multiple sclerosis: how real-world evidence compares with randomized clinical trials?

INTRODUCTION

In recent years, many treatment options have become available for relapsing remitting MS. Randomized clinical trials and real-world studies are complementary sources of information, and together have the potential to offer a comprehensive understanding of the safety and efficacy profiles of each drug, a critical factor for a personalized management of the disease.

AREAS COVERED

In this review, the authors provide an up-to-date review of both RCTs and real-world studies assessing the safety and efficacy profiles of recently developed disease-modifying drugs for relapsing remitting MS. These include fingolimod, teriflunomide, dimethyl fumarate, alemtuzumab and ocrelizumab.

EXPERT OPINION

From the authors' review of the literature, the efficacy profiles resulted from RCTs were confirmed by observational studies with regard to the disease-modifying drugs considered. The magnitude of the effects on annualized relapse rates and MRI active lesions was generally even larger in the observational studies compared to RCTs. From the safety point of view, observational studies revealed new adverse events, mostly in the area of bacterial and opportunistic infections, not seen in the relative registration programme. This is a very important gain because it allows to elaborate appropriate strategies to prevent and handle the risks.

The Irony of Humanization: Alemtuzumab, the First, But One of the Most Immunogenic, Humanized Monoclonal Antibodies

Alemtuzumab was designed to reduce the immunogenicity of the parent CD52-specific rat immunoglobulin. Although originally marketed for use in cancer (Mabcampath®), alemtuzumab is currently licensed and formulated for the treatment of relapsing multiple sclerosis (Lemtrada®). Perhaps due to its history as the first humanized antibody, the potential of immunogenicity of the molecule has been considered inconsequential, and anti-drug antibodies (ADA) responses were similarly reported as being clinically insignificant. Nonetheless, despite humanization and depletion of peripheral T and B cells, alemtuzumab probably generates the highest frequency of binding and neutralizing ADA of all humanized antibodies currently in clinical use, and they occur rapidly in a large majority of people with MS (pwMS) on alemtuzumab treatment. These ADA appear to be an inherent issue of the biology of the molecule-and more importantly, the target-such that avoidance of immunogenicity-related effects has been facilitated by the dosing schedule used in clinical practice. At the population level this enables the drug to work in most pwMS, but in some individuals, as we show here, antibody neutralization appears to be sufficiently severe to reduce efficacy and allow disease breakthrough. It is therefore imperative that efficacy of lymphocyte depletion and the anti-drug response is monitored in people requiring additional cycles of treatment, notably following disease breakthrough. This may help inform whether to re-treat or to switch to another disease-modifying treatment.

Do clinical trials for new disease modifying treatments include real world patients with multiple sclerosis?

We often see that clinical and demographic characteristics of real-world studies (RWS) do not differ from patients included in randomized controlled trials (RCT).

OBJECTIVE

to compare clinical and demographic aspects of patients included in RCT and RWS that evaluated new disease modifying treatment in multiple sclerosis (MS).

METHODS

a systematic non-language-restricted literature search of RCT and RWS that evaluated new disease modifying treatments (natalizumab, alemtuzumab, ocrelizumab, fingolimod, teriflunomide, dimethyl fumarate and cladribine) from January 2005 to January 2019. Demographic and clinical data were extracted, described and compared.

RESULTS

18 RCT and 73 RWS were included. We found no differences in clinical and demographic aspects between RCT and RWS except in the frequency of naïve patients included in RCT vs. RWS 65.6% (95%CI 52-74) vs. 36.4% (95%CI 21-46), respectively, (p = 0.013) at study entry, as well as for the inclusion of patients that used previous treatment 34.4% (95%CI 22-41) vs. 63.6% (95%CI 53-74) in RCT and RWS, respectively,(p = 0.007) at study entry.

CONCLUSION

We did not observe significant differences in most clinical and demographic aspects of included patients in RCT and RWS. Studies that include the full spectrum of MS patients followed in clinical practice are needed.

Fingolimod Rebound: A Review of the Clinical Experience and Management Considerations

Because the treatment of multiple sclerosis (MS) may span decades, the need often arises to make changes to the treatment plan in order to accommodate changing circumstances. Switching drugs, or the discontinuation of immunomodulatory agents altogether, may leave patients vulnerable to relapse or disease progression. In some cases, severe MS disease activity is noted clinically and on MRI after treatment withdrawal. When this disease activity is disproportionate to the pattern observed prior to treatment initiation, patients are said to have experienced rebound. Of the US Food and Drug Administration (FDA)-approved agents to treat MS, the drugs most commonly implicated in rebound are natalizumab and fingolimod. In this review based on the reported cases and data from clinical trials, we characterize disease rebound after fingolimod cessation. We also outline fingolimod rebound management considerations, summarizing what evidence is available to help clinicians mitigate the risk of rebound, switch therapies, and treat rebound events when they occur. The commonly encountered situation of fingolimod discontinuation prior to pregnancy is also discussed.

Switching from fingolimod to alemtuzumab in patients with highly active relapsing-remitting multiple sclerosis: Α case series

BACKGROUND

The management of "aggressive" and "highly-active" relapsing-remitting multiple sclerosis remains problematic. Although a number of highly efficacious agents are currently available, the optimal timing of their use and the balancing between efficacy and immediate and long-term consequences are still a matter of conjecture.

METHODS

We describe the clinical, radiological and immunological profile of three multiple sclerosis patients with persistent clinical and radiological disease activity under fingolimod treatment. After fingolimod cessation patients demonstrated severe disease exacerbation and were successfully treated with alemtuzumab.

RESULTS

All patients experienced significant improvement after the administration of alemtuzumab and achieved no evidence of disease activity status that persisted after a median of 19 months of follow-up (range: 17-25 months). Confirmed disability improvement was achieved in all cases. Quantitative MRI data demonstrated a reduction of the T2 lesion load in 2 out of 3 patients and complete abrogation of inflammatory activity in all patients after the administration of alemtuzumab. Α patient presented a previously unreported, persistent lymphocytosis after alemtuzumab administration, that was not associated with infectious, lymphoproliferative or autoimmune diseases and had no apparent clinical implications.

CONCLUSIONS

Alemtuzumab appears to be an effective and safe short-term therapeutic option both as a rescue therapy for the disease flare-up associated with fingolimod withdrawal, as well as for the reversal of the deteriorating course observed in patients who fail treatment with fingolimod.

Efficacy of alemtuzumab over 6 years in relapsing-remitting multiple sclerosis patients who relapsed between courses 1 and 2: Post hoc analysis of the CARE-MS studies

BACKGROUND

Alemtuzumab is administered as two annual courses for relapsing-remitting multiple sclerosis (MS). Patients may relapse before completing the two-course regimen.

OBJECTIVE

The objective was to evaluate 6-year outcomes in patients who relapsed between alemtuzumab Courses 1 and 2 (early relapsers).

METHODS

Post hoc analysis of patients from the Comparison of Alemtuzumab and Rebif^® Efficacy in Multiple Sclerosis (CARE-MS) studies who enrolled in the extension.

RESULTS

Early relapsers (CARE-MS I: 15%; CARE-MS II: 24%) had more relapses in 1-2 years pre-alemtuzumab and higher mean baseline Expanded Disability Status Scale score than patients without relapse. Their annualized relapse rate declined from Year 1 (CARE-MS I: 1.3; CARE-MS II: 1.2) to Year 2 following Course 2 (0.3; 0.5) and remained low thereafter. Over 6 years, 60% remained free of 6-month confirmed disability worsening; 24% (CARE-MS I) and 34% (CARE-MS II) achieved 6-month confirmed disability improvement. During Year 6, 69% (CARE-MS I) and 68% (CARE-MS II) were free of magnetic resonance imaging (MRI) disease activity. Median percent yearly brain volume loss (Year 1: -0.67% (CARE-MS I); -0.47% (CARE-MS II)) declined after Course 2 (Year 6: -0.24%; -0.13%).

CONCLUSION

Early relapsers' outcomes improved after completing the second alemtuzumab course. These findings support administering the approved two-course regimen to maximize clinical benefit.

CLINICALTRIALS.GOV REGISTRATION NUMBERS

CARE-MS I, II, extension: NCT00530348, NCT00548405, NCT00930553.

Clinical recommendations for the use of ocrelizumab in patients with multiple sclerosis

The paper presents a detailed algorithm for the treatment and follow-up of patients with recurrent multiple sclerosis and primary progressive multiple sclerosis in the use of ocrelizumab.

Rebound of multiple sclerosis activity after fingolimod withdrawal due to planning pregnancy: Analysis of predisposing factors

BACKGROUND

Rebound of multiple sclerosis (MS) activity has been described after the withdrawal of high-efficacy drugs, but its impact during pregnancy is less known. We describe a series of cases of rebound syndrome after the cessation of fingolimod due to pregnancy planning.

METHODS

The clinical and radiological data of 7 MS patients who discontinued fingolimod therapy between May 2012 and March 2018 to plan a pregnancy was analysed.

RESULTS

Three (42.8%) of the 7 patients experienced a rebound effect, all of whom became pregnant. During pregnancy, the 3 patients had a mean (SD) of 5.3 (1.3) relapses, and 13 of the 15 relapses were treated with intravenous steroids and/or immunoglobulin. These patients experienced a median increase of 3 points in the Expanded Disability Status Scale (range, 2-4), as well as a median increase of 27 new gadolinium-enhancing lesions (range, 9-40) and 38 new T2 lesions in a post-partum MRI (range, 21-70). The 3 pregnancies resulted in the delivery of healthy babies. A strong correlation was found between the lymphocyte count at fingolimod onset and the annual relapse rate in the period without therapy (r= -0.84, p = 0.005). The time to first relapse was shorter in patients who had <300/μl lymphocytes at fingolimod onset (median time 46 vs 426 days, p = 0.010).

CONCLUSION

Rebound activity after fingolimod suspension represents a severe long-lasting inflammatory syndrome that may affect up to 40% of female MS patient who discontinue therapy due to pregnancy planning. Lymphopenia (<300/μl) in the first 3 months of fingolimod onset may predispose patients to suffer earlier and higher disease activity upon cessation.

Learning from other autoimmunities to understand targeting of B cells to control multiple sclerosis

Although many suspected autoimmune diseases are thought to be T cell-mediated, the response to therapy indicates that depletion of B cells consistently inhibits disease activity. In multiple sclerosis, it appears that disease suppression is associated with the long-term reduction of memory B cells, which serves as a biomarker for disease activity in many other CD20+ B cell depletion-sensitive, autoimmune diseases. Following B cell depletion, the rapid repopulation by transitional (immature) and naïve (mature) B cells from the bone marrow masks the marked depletion and slow repopulation of lymphoid tissue-derived, memory B cells. This can provide long-term protection from a short treatment cycle. It seems that memory B cells, possibly via T cell stimulation, drive relapsing disease. However, their sequestration in ectopic follicles and the chronic activity of B cells and plasma cells in the central nervous system may drive progressive neurodegeneration directly via antigen-specific mechanisms or indirectly via glial-dependent mechanisms. While unproven, Epstein-Barr virus may be an aetiological trigger of multiple sclerosis. This infects mature B cells, drives the production of memory B cells and possibly provides co-stimulatory signals promoting T cell-independent activation that breaks immune tolerance to generate autoreactivity. Thus, a memory B cell centric mechanism can integrate: potential aetiology, genetics, pathology and response to therapy in multiple sclerosis and other autoimmune conditions with ectopic B cell activation that are responsive to memory B cell-depleting strategies.

Outcomes after fingolimod to alemtuzumab treatment shift in relapsing-remitting MS patients: a multicentre cohort study

BACKGROUND

A high reactivation of multiple sclerosis (MS) was reported in patients treated with alemtuzumab after fingolimod. We aimed to understand whether this shift enhanced the risk for reactivation in a real-life cohort.

METHODS

Subjects with relapsing MS, shifting from fingolimod to alemtuzumab were enrolled. We collected the following data: age, sex, disease duration, relapses after fingolimod withdrawal, new T2/gadolinium (Gd)-enhancing lesions in the last magnetic resonance imaging (MRI) during fingolimod and in the first, while on alemtuzumab, lymphocyte counts at alemtuzumab start, and Expanded Disability Status Scale (EDSS) before and after alemtuzumab.

RESULTS

We enrolled 77 patients (women 61 (79%); mean age 36.2 years (SD 9.6), and disease duration 12.3 years (SD 6.8) at fingolimod discontinuation; median washout 1.8 months). The annualised relapse rate was 0.89 during fingolimod, 1.32 during washout, and 0.15 after alemtuzumab (p = 0.001). The EDSS changed from a median of 3 (IQR 2-4) at the end of fingolimod to 2.5 after alemtuzumab (IQR 1.5-4) (p = 0.013). The washout length and the lymphocyte count before alemtuzumab were not associated with EDSS change after alemtuzumab (p = 0.59 and p = 0.33, respectively). MRI activity decreased after alemtuzumab compared to that during fingolimod (p = 0.001). At alemtuzumab start, lymphocyte counts were < 0.8 × 10³/mL in 21 patients.

CONCLUSIONS

In our cohort, alemtuzumab reduced relapse, new T2/Gd-enhancing lesions, and EDSS score, as compared to the previous periods (fingolimod/washout). These results were not related to washout length or lymphocyte counts. Therefore, a rapid initiation of alemtuzumab after fingolimod does not seem to be a risk factor for MS reactivation.

Stabilization Without Rituximab After Disease Activation in an Alemtuzumab-Treated Patient with Multiple Sclerosis and a Literature Overview

There has been an increasing number of reports describing B-cell-associated disease activation in patients with multiple sclerosis after alemtuzumab treatment. Herein, 4.5 months after a first alemtuzumab infusion, a 33-year-old female patient had altered gait and vision loss associated with gadolinium enhancement of the optic nerves and chiasm on brain magnetic resonance imaging. The patient's blood showed normal B-cell counts concurrent with abnormally low T-cell counts. The patient stabilized after receiving steroids and prolonged plasma exchange without the use of rituximab. This case report adds to the growing body of literature of B-cell-associated disease activation after alemtuzumab infusion and provides a therapeutic strategy to stabilize patients when rituximab is not readily available or if contraindications to its use exist.

Treatment with alemtuzumab or rituximab after fingolimod withdrawal in relapsing-remitting multiple sclerosis is effective and safe

BACKGROUND

It has been described that treating relapsing-remitting multiple sclerosis (RRMS) patients with alemtuzumab following fingolimod could be less effective due to the different dynamics of lymphocyte repopulation. Effectiveness and safety of alemtuzumab compared to rituximab after fingolimod withdrawal were analyzed.

PATIENTS AND METHODS

A follow-up of a cohort of RRMS patients treated with alemtuzumab or rituximab after fingolimod withdrawal was accomplished. Effectiveness, measured by the percentage of patients with no evidence of disease activity (NEDA), and the presence of side effects (SE) were registered.

RESULTS

Fifty-five patients, 28 with alemtuzumab and 27 with rituximab, were analyzed. No differences in the washout period or in the baseline lymphocytes counts were observed. After a mean follow-up period of 28.8 months, the annualized relapsing rate was significantly reduced in the alemtuzumab group from 1.29 to 0.004 (p < 0.001) and in the rituximab group from 1.24 to 0.02 (p < 0.001), without differences. A significant reduction of the median EDSS from 2.8 to 2.0 in the alemtuzumab group and from 3.5 to 2.5 (p < 0.01) in the rituximab group was observed, without differences. Eighty-two per cent (n = 28) of patients in alemtuzumab group and 69.2% (n = 26) in rituximab group achieved NEDA criteria, without differences (p = 0.3). Symptoms related to the infusion were the most frequent SE in both groups. No serious SE were registered.

CONCLUSION

Treating RRMS patients with alemtuzumab or rituximab after fingolimod withdrawal is effective and safe, without significant differences between both groups in our series.

Alemtuzumab for the treatment of multiple sclerosis

INTRODUCTION

Alemtuzumab is a monoclonal antibody that targets for the destruction CD52+ cells, particularly B and T cells. Alemtuzumab is approved in more than 50 countries around the world for the treatment of adult patients with relapsing remitting multiple sclerosis (MS). Areas covered: In this review, the authors summarize biological, clinical and safety data related to the use of alemtuzumab in patients with MS. The authors then provide their expert opinion on alemtuzumab and the field as of whole before providing their perspectives for the future. Expert opinion: Alemtuzumab is highly efficacious; more so than first line treatments but comparable to natalizumab. Treatment schedule makes alemtuzumab administration easy and attractive to patients. However, its safety profile makes it a choice for a very limited number of patients, in a specific disease window. As of now, a cure for MS remains elusive and there is an unmet need for a safe and highly potent agent at the level of and beyond the blood brain barrier.

Ozanimod for the treatment of relapsing remitting multiple sclerosis

INTRODUCTION

Ozanimod is a selective sphingosine 1-phosphate receptor 1 and 5 modulator under development by Celgene, for the treatment of relapsing remitting multiple sclerosis. Extensive clinical experience has become available for the related compound fingolimod, favoring the sphingosine 1-phosphate therapeutic concept. Off-target effects have been attributed to its low receptor specificity and have prompted the development of next generation sphingosine 1-phosphate receptor modulators. Areas covered: The authors evaluate the literature of ozanimod, using the PubMed database as well as repositories of the European Committee for Treatment and Research in Multiple Sclerosis and the American and European Academy of Neurology. Specifically, the authors cover and discuss the preclinical data on ozanimod, pharmacokinetics and dynamics, and data on efficacy and safety from the pivotal trials. Expert opinion: Superiority of ozanimod over intramuscular interferon β-1a with regard to reduction in annualized relapse rate and magnetic resonance imaging outcomes has been shown in two phase III trials. The beneficial effect on brain volume and gray matter loss are encouraging and in line with data on other newer immunomodulators. Ozanimod is a valuable contribution to the therapeutic armamentarium in MS, although the effect on disability progression is unclear and requires further investigations.

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.

Extensive Multiple Sclerosis Reactivation after Switching from Fingolimod to Rituximab

During treatment with fingolimod, B cells are redistributed from blood to secondary lymphoid organs, where they are protected from the effect of anti-CD20 and other cell-depleting therapies. We describe a multiple sclerosis patient who had almost complete depletion of B cells in blood during and shortly after treatment with fingolimod. He developed severe disease activity resembling immune reconstitution syndrome after switching from fingolimod to rituximab, with first dose being six weeks after fingolimod cessation. Following recommendations from the Swedish MS Association, rituximab treatment was started as one single dose of 1000 mg. In patients treated with fingolimod, pathogenic B cells may still be sequestered in secondary lymph nodes if this dose is given early. To deplete such B cells as they egress from the lymph nodes, we propose that a second dose of rituximab a few weeks after the first dose should be considered.

Cladribine treatment of multiple sclerosis is associated with depletion of memory B cells

Background

The mechanism of action of oral cladribine, recently licensed for relapsing multiple sclerosis, is unknown.

Objective

To determine whether cladribine depletes memory B cells consistent with our recent hypothesis that effective, disease-modifying treatments act by physical/functional depletion of memory B cells.

Methods

A cross-sectional study examined 40 people with multiple sclerosis at the end of the first cycle of alemtuzumab or injectable cladribine. The relative proportions and absolute numbers of peripheral blood B lymphocyte subsets were measured using flow cytometry. Cell-subtype expression of genes involved in cladribine metabolism was examined from data in public repositories.

Results

Cladribine markedly depleted class-switched and unswitched memory B cells to levels comparable with alemtuzumab, but without the associated initial lymphopenia. CD3⁺ T cell depletion was modest. The mRNA expression of metabolism genes varied between lymphocyte subsets. A high ratio of deoxycytidine kinase to group I cytosolic 5′ nucleotidase expression was present in B cells and was particularly high in mature, memory and notably germinal centre B cells, but not plasma cells.

Conclusions

Selective B cell cytotoxicity coupled with slow repopulation kinetics results in long-term, memory B cell depletion by cladribine. These may offer a new target, possibly with potential biomarker activity, for future drug development.

Electronic supplementary material

The online version of this article (10.1007/s00415-018-8830-y) contains supplementary material, which is available to authorized users.

Efficacy and Safety of the Newer Multiple Sclerosis Drugs Approved Since 2010

Multiple sclerosis treatment faces tremendous changes as a result of the approval of new medications. The new medications have differing safety considerations and risks after long-term treatment, which are important for treating physicians to optimize and individualize multiple sclerosis care. Since the approval of the first multiple sclerosis capsule, fingolimod, the armamentarium of multiple sclerosis therapy has grown with the orally available medications dimethyl fumarate and teriflunomide. Fingolimod is mainly associated with cardiac side effects, dimethyl fumarate with bowel symptoms. Several reports about progressive multifocal leukoencephalopathy as a result of dimethyl fumarate or fingolimod therapy raised the awareness of fatal opportunistic infections. Alemtuzumab, a CD52-depleting antibody, is highly effective in reducing relapses but leads to secondary immunity with mainly thyroid disorders in about 30% of patients. Development of secondary B-cell-mediated disease might also be a risk of this antibody. The follow-up drug of the B-cell-depleting antibody rituximab, ocrelizumab, is mainly associated with infusion-related reactions; long-term data are scarce. The medication daclizumab high yield process, acting via the activation of CD56^bright natural killer cells, can induce the elevation of liver function enzymes, but also fulminant liver failure has been reported. Therefore, daclizumab has been retracted from the market. Long-term data on the purine nucleoside cladribine in MS therapy, recently authorized in the European Union, have been acquired during the long-term follow-up of the cladribine studies. The small molecule laquinimod is currently under development. We review data of clinical trials and their extensions regarding long-term efficacy and side effects, which might be associated with long-term treatment.

Activation of disease during therapy with alemtuzumab in 3 patients with multiple sclerosis

OBJECTIVE

To report 3 patients with multiple sclerosis showing severe activation of disease during immunotherapy with alemtuzumab.

METHODS

Retrospective case series.

RESULTS

Patient 1, a 21-year-old woman, developed severe cognitive impairment, sight deterioration, severe gait ataxia, urinary retention, and extensive progression of cerebral lesion load, including new lesions that exhibited gadolinium ring enhancement and dominance of CD19/20-positive B lymphocytes, 6 months after induction of alemtuzumab. Patient 2, a 28-year-old man, developed left-sided hemihypesthesia and ∼60 new cerebral and spinal lesions including lesions with gadolinium ring enhancement 6 months after induction of alemtuzumab. Patient 3, a 37-year-old woman, developed ataxia and numbness of the left thigh, 16 new gadolinium-positive supratentorial lesions, and partly ring-enhancing and dominance of CD19/20-positive B lymphocytes 6 months after induction of alemtuzumab.

CONCLUSION

This is a case series reporting severe activation of disease during immunotherapy with alemtuzumab. All patients showed onset of symptoms 6 months after induction of alemtuzumab, strikingly similar MRI lesion morphology, and unexpected high total B cell count, which may suggest a B-cell-mediated activation of disease. Whether this is due to different rates of B- and T cell repopulation has to be the subject of further research. Moreover, further effects on the interactions between the adaptive and innate immunity as well as between B and T cell lineages might explain the observed disease activation.

Alemtuzumab depletion failure can occur in multiple sclerosis

Alemtuzumab is a lymphocyte-depleting antibody and one of the most effective treatments for relapsing multiple sclerosis. However, it also causes loss of immune-tolerance leading to secondary autoimmunity and marked anti-drug antibody responses. Although these anti-drug responses have been reported to be of no significance, we hypothesized that they will affect the depleting capacity and treatment response in some individuals. This was found following analysis of the regulatory submission of the pivotal phase III trials, which was obtained from the European Medicines Agency. At the population level there was lack of influence of 'ever-positive' alemtuzumab-specific antibody responses on lymphocyte depletion, clinical efficacy and adverse effects during the 2-year trial. This was not surprising as no one before the first infusion, and only 0·6% of people before the second-infusion, had pre-infusion, neutralizing antibodies (NAbs). However, at the individual level, NAbs led to poor lymphocyte depletion. Importantly, it was evident that 31% of people had NAbs and 75% had binding antibodies at the end of treatment-cycle 2, which suggests that problems may occur in people requiring additional alemtuzumab cycles. In addition, we also identified individuals, following 'post-marketing' alemtuzumab use, whose lymphocyte level was never effectively depleted after the first infusion cycle. Hence, although alemtuzumab depletes lymphocytes in most individuals, some people fail to deplete/deplete poorly, probably due to biological-response variation and NAbs, and this may lead to treatment failure. Monitoring depletion following infusion and assessment of the neutralizing response before re-infusion may help inform the decision to retreat or switch therapy to limit treatment failure.

Lack of CD4+ T cell percent decrease in alemtuzumab-treated multiple sclerosis patients with persistent relapses

Alemtuzumab, a highly effective treatment for relapsing remitting multiple sclerosis (RRMS), induces lymphopenia especially of CD4+ T cells. Here, we report the atypical CD4+ T population behaviour of two patients with persistent disease activity despite repeated alemtuzumab treatments. Whereas lymphocytes count decreased and fluctuated accordingly to alemtuzumab administration, their CD4+ cell percentage was not or just mildly affected and was slightly below the lowest normal limit already before alemtuzumab. These cases anticipate further studies aimed to investigate whether the evaluation of the CD4+ cell percentage could represent a helpful tool to address the individual clinical response to alemtuzumab.

Interpreting Lymphocyte Reconstitution Data From the Pivotal Phase 3 Trials of Alemtuzumab

Importance

Alemtuzumab, a CD52-depleting monoclonal antibody, effectively inhibits relapsing multiple sclerosis (MS) but is associated with a high incidence of secondary B-cell autoimmunities that limit use. These effects may be avoided through control of B-cell hyperproliferation.

Objective

To investigate whether the data describing the effect of alemtuzumab on lymphocyte subsets collected during the phase 3 trial program reveal mechanisms explaining efficacy and the risk for secondary autoimmunity with treatment of MS.

Design, Setting, and Participants

Lymphocyte reconstitution data from regulatory submissions of the pivotal Comparison of Alemtuzumab and Rebif Efficacy in Multiple Sclerosis I and II (CARE-MS I and II) trials were obtained from the European Medicines Agency via Freedom of Information requests. Data used in this study were reported from June 22 to October 12, 2016.

Main Outcomes and Measures

Tabulated data from T- and B-lymphocyte subset analysis and antidrug antibody responses were extracted from the supplied documents.

Results

Alemtuzumab depleted CD4+ T cells by more than 95%, including regulatory cells (-80%) and CD8+ T cells (>80% depletion), which remained well below reference levels throughout the trials. However, although CD19+ B cells were initially also depleted (>85%), marked (180% increase) hyperrepopulation of immature B cells occurred with conversion to mature B cells over time. These lymphocyte kinetics were associated with rapid development of alemtuzumab-binding and -neutralizing antibodies and subsequent occurrence of secondary B-cell autoimmunity. Hyperrepopulation of B cells masked a marked, long-term depletion of CD19+ memory B cells that may underpin efficacy in MS.

Conclusions and Relevance

Although blockade of memory T and B cells may limit MS, rapid CD19+ B-cell subset repopulation in the absence of effective T-cell regulation has implications for the safety and efficacy of alemtuzumab. Controlling B-cell proliferation until T-cell regulation recovers may limit secondary autoimmunity, which does not occur with other B-cell-depleting agents.

Alemtuzumab in the long-term treatment of relapsing-remitting multiple sclerosis: an update on the clinical trial evidence and data from the real world

Alemtuzumab is a humanized monoclonal antibody approved for the treatment of relapsing-remitting multiple sclerosis (RRMS), given as two annual courses on five consecutive days at baseline and on three consecutive days 12 months later. Here we provide an update on the long-term efficacy and safety of alemtuzumab in RRMS, including real-world experience, and advances in our understanding of its mechanism of action. Recent data from the phase II/III extension study have demonstrated that alemtuzumab reduces relapse rates, disability worsening, and the rate of brain volume loss over the long term, with many patients achieving no evidence of disease activity. In high proportions of patients, preexisting disability remained stable or improved. Alemtuzumab is associated with a consistent safety profile over the long term, with no new safety signals emerging and the overall annual incidence of reported adverse events decreasing after the first year on treatment. Acyclovir prophylaxis reduces herpetic infections, and monitoring has been shown to mitigate the risk of autoimmune adverse events, allowing early detection and overall effective management. Data from clinical practice and ongoing observational studies are providing additional information on the real-world use of alemtuzumab. Recent evidence on the mechanism of action of alemtuzumab indicates that in addition to its previously known effects of inducing depletion and repopulation of T and B lymphocytes, it also results in a relative increase of cells with memory and regulatory phenotypes and a decrease in cells with a proinflammatory signature, and may further promote an immunoregulatory environment through an impact on other innate immune cells (e.g. dendritic cells) that play a role in MS. These effects may allow preservation of innate immunity and immunosurveillance. Together, these lines of evidence help explain the durable clinical efficacy of alemtuzumab, in the absence of continuous treatment, in patients with RRMS.