Efficacy of natalizumab in second line therapy of relapsing-remitting multiple sclerosis: results from a multi-center study in German speaking countries

Natalizumab treatment of multiple sclerosis - a Danish nationwide study with 13 years of follow-up

BACKGROUND

Natalizumab is a widely used high-efficacy treatment in multiple sclerosis (MS). Real-world evidence regarding long-term effectiveness and safety is warranted. We performed a nationwide study evaluating prescription patterns, effectiveness, and adverse events.

METHODS

A nationwide cohort study using the Danish MS Registry. Patients initiating natalizumab between June 2006 and April 2020 were included. Patient characteristics, annualized relapse rates (ARRs), confirmed Expanded Disability Status Scale (EDSS) score worsening, MRI activity (new/enlarging T2- or gadolinium-enhancing lesions), and reported adverse events were evaluated. Further, prescription patterns and outcomes across different time periods ("epochs") were analysed.

RESULTS

In total, 2424 patients were enrolled, with a median follow-up time of 2.7 years (interquartile range (IQR) 1.2-5.1). In recent epochs, patients were younger, had lower EDSS scores, had fewer pre-treatment relapses and were more often treatment naïve. At 13 years of follow-up, 36% had a confirmed EDSS worsening. On-treatment ARR was 0.30, corresponding to a 72% reduction from pre-initiation. MRI activity was rare, 6.8% had activity within 2-14 months from treatment start, 3.4% within 14-26 months, and 2.7% within 26-38 months. Approximately 14% of patients reported adverse events, with cephalalgia constituting the majority. During the study, 62.3% discontinued treatment. Of these, the main cause (41%) was due to JCV antibodies, while discontinuations due to disease activity (9%) or adverse events (9%) were less frequent.

CONCLUSION

Natalizumab is increasingly used earlier in the disease course. Most patients treated with natalizumab are clinically stable with few adverse events. JCV antibodies constitute the main cause for discontinuation.

Effect of natalizumab treatment on the rate of No Evidence of Disease Activity in young adults with multiple sclerosis in relation to pubertal stage

Approximately 40% of young-onset multiple sclerosis (MS) patients experience breakthrough disease, which carries a high risk for long-term disability, and requires using therapies beyond traditional first-line agents. Despite the increasing use of newer disease-modifying treatments (DMTs) in this population, data are not available to guide the need for escalating DMTs and there is a scarcity of data on the effects of natalizumab in children and young adults with active disease. We performed a retrospective analysis of the rate of No Evidence of Disease Activity (NEDA), tolerability, and safety of natalizumab in a multi-center cohort of 36 children and young adults with highly active MS. All patients had active disease and initiated treatment with natalizumab. The primary endpoint was the rate of achieving NEDA-3 status, within two years of natalizumab treatment. To examine a possible effect of age on the outcome of treatment, outcomes were also analyzed by pre-pubertal (n = 13 children aged 9-13 years) and pubertal subgroups (n = 23 young adolescents aged 14-20 years). The NEDA-3 status of the pre-pubertal group was 92% in the first and second year and in the pubertal group - 96% in the first year and 92% in the second year. Natalizumab reduced the number and volume of brain lesions in both pre-pubertal and pubertal groups. Treatment was well-tolerated, only 8 patients (22.2%) had adverse events during the 2-year study period. Our analysis shows that natalizumab is effective and well-tolerated in pre-pubertal and pubertal MS patients.

Real-World Data Regarding Long-Term Administration of Natalizumab from a Neurology Department along Literature Review

BACKGROUND

Natalizumab is a humanized monoclonal antibody with high efficacy and an acceptable safety profile used in the treatment of patients with multiple sclerosis (MS).

OBJECTIVES

Our aim was to report data regarding long-term administration of Natalizumab in patients with relapsing-remitting multiple sclerosis (RRMS) from our clinic.

METHODS

A retrospective observational study was performed including RRMS patients who underwent treatment with ≥ 24 Natalizumab infusions. We analyzed the EDSS values, the relapse rate and the rate and type of adverse events related to Natalizumab administration.

RESULTS

51 subjects were included with a predominance of women (62.74%), an average age of 40.43±1.49 years, a mean disease duration of 9.86±0.7 years and mean number of Natalizumab infusions of 45.58±2.74. An increased number of patients (80.39%) were relapse-free and there was observed a mild reduction of the mean EDSS value following Natalizumab initiation in patients who had not been treated with other disease modifying therapies anteriorly. Among the encountered adverse events we registered: increased liver transaminases (13.72%), local infections (7.84%) and dysmenorrhea in one patient. The rate of severe adverse events was 3.92 and there were registered no cases of Progressive Multifocal Leukoencephalopathy (PML).

CONCLUSIONS

Natalizumab proves to be effective, has an adequate safety profile and can be administered with good tolerability for a rather extended period of time, provided that the patients are closely monitored.

PML risk is the main factor driving the choice of discontinuing natalizumab in a large multiple sclerosis population: results from an Italian multicenter retrospective study

BACKGROUND

Natalizumab (NTZ) is an effective treatment for relapsing-remitting multiple sclerosis (RRMS). However, patients and physicians may consider discontinuing NTZ therapy due to safety or efficacy issues. The aim of our study was to evaluate the NTZ discontinuation rate and reasons of discontinuation in a large Italian population of RRMS patients.

MATERIALS AND METHODS

The data were extracted from the Italian MS registry in May 2018 and were collected from 51,845 patients in 69 Italian multiple sclerosis centers. MS patients with at least one NTZ infusion in the period between June 1st 2012 to May 15th 2018 were included. Discontinuation rates at each time point were calculated. Reasons for NTZ discontinuation were classified as "lack of efficacy", "progressive multifocal leukoencephalopathy (PML) risk" or "other".

RESULTS

Out of 51,845, 5151 patients, 3019 (58.6%) females, with a mean age of 43.6 ± 10.1 years (median 40), were analyzed. Out of 2037 (39.5%) who discontinued NTZ, a significantly higher percentage suspended NTZ because of PML risk compared to lack of efficacy [1682 (32.7% of 5151) vs 221 (4.3%), p < 0.001]; other reasons were identified for 99 (1.9%) patients. Patients discontinuing treatment were older, had longer disease duration and worse EDSS at the time of NTZ initiation and at last follow-up on NTZ treatment. The JCV index and EDSS at baseline were predictors for stopping therapy (HR 2.94, 95% CI 1.22-4.75; p = 0.02; HR 1.36, 95% CI 1.18-5.41; p = 0.04).

CONCLUSIONS

Roughly 60% of MS patients stayed on NTZ treatment during the observation period. For those patients in whom NTZ discontinuation was required, it was mainly due to PML concerns.

Natural killer cells in inflammatory autoimmune diseases

Natural killer (NK) cells are a specialised population of innate lymphoid cells (ILCs) that help control local immune responses. Through natural cytotoxicity, production of cytokines and chemokines, and migratory capacity, NK cells play a vital immunoregulatory role in the initiation and chronicity of inflammatory and autoimmune responses. Our understanding of their functional differences and contributions in disease settings is evolving owing to new genetic and functional murine proof-of-concept studies. Here, we summarise current understanding of NK cells in several classic autoimmune disorders, particularly in rheumatoid arthritis (RA), multiple sclerosis (MS), systemic lupus erythematosus (SLE) and type 1 diabetes mellitus (T1DM), but also less understood diseases such as idiopathic inflammatory myopathies (IIMs). A better understanding of how NK cells contribute to these autoimmune disorders may pave the way for NK cell-targeted therapeutics.

Infusion-related events during natalizumab: No need for post-infusion monitoring

This retrospective cohort study assessed the timing of infusion-related adverse events (IAEs) during natalizumab (NTZ) administration in well-documented relapsing-remitting multiple sclerosis (RRMS) patients who had received NTZ infusions in our centre between 2006 and 2018. In 225 RRMS patients (14,174 NTZ infusions), 276 IAEs (1.95%) occurred in 60 patients. All documented severe IAE occurred during infusion. Of the 19 moderate adverse events, 17 were during infusion. None of the reactions that occurred after the infusion required intervention. These results suggest that post-infusion monitoring is not necessary in patients who do not have an adverse event during infusion.

Infusion-related reactions during Natalizumab treatment: Do we still need a post-infusion observation period?

BACKGROUND

Natalizumab (NTZ) is a humanized monoclonal antibody used in the treatment of relapsing remitting multiple sclerosis. Although NTZ is usually well-tolerated, infusion-related reactions (IRRs) may occur, and the patients have to be monitored during the infusion and for one hour afterwards.

OBJECTIVE

To identify frequency and severity of IRRs during NTZ infusions and one-hour post-infusion observation period in a clinical practice setting.

METHODS

Multicenter, observational study involving three Swiss (Lugano, St. Gallen and Luzern) and two Italian (Milano and Napoli) tertiary MS centers. Predisposing factors to IRRs were investigated using multivariate Cox regression models.

RESULTS

A total of 11'133 infusions received by 302 MS patients were analyzed (68.9% females, median age 33.6 years, median EDSS 2.5). IRRs occurred in 24 (8%) patients during NTZ infusions and in 7 (2%) during one-hour post-infusion. Only 8 patients needed pharmacological treatment, of whom 7 during NTZ infusion. Age, sex and history of allergies were not associated with risks for IRR. The frequency of post infusion IRRs after the fifth cycle was low compared to that during the first four infusions (0.83% vs 0.06%).

CONCLUSION

In our cohort, NTZ associated IRR mainly occurred during the infusion period compared to the one-hour observational period. Also, the first IRR exclusively occurred within the first 4 NTZ administrations. However, further multi-center studies with a larger sample size are needed to capture rare and serious events that could emerge during the observational period and to make clinical recommendations.

Gray matter atrophy in multiple sclerosis despite clinical and lesion stability during natalizumab treatment

BACKGROUND

Brain volume loss is an important surrogate marker for assessing disability in MS; however, contribution of gray and white matter to the whole brain volume loss needs further examination in the context of specific MS treatment.

OBJECTIVES

To examine whole and segmented gray, white, thalamic, and corpus callosum volume loss in stable patients receiving natalizumab for 2-5 years.

METHODS

This was a retrospective study of 20 patients undergoing treatment with natalizumab for 24-68 months. Whole brain volume loss was determined with SIENA. Gray and white matter segmentation was done using FAST. Thalamic and corpus callosum volumes were determined using Freesurfer. T1 relaxation values of chronic hypointense lesions (black holes) were determined using a quantitative, in-house developed method to assess lesion evolution.

RESULTS

Over a mean of 36.6 months, median percent brain volume change (PBVC) was -2.0% (IQR 0.99-2.99). There was decline in gray (p = 0.001) but not white matter (p = 0.6), and thalamic (p = 0.01) but not corpus callosum volume (p = 0.09). Gray matter loss correlated with PBVC (Spearman's r = 0.64, p = 0.003) but not white matter (Spearman's r = 0.42, p = 0.07). Age significantly influenced whole brain volume loss (p = 0.010, multivariate regression), but disease duration and baseline T2 lesion volume did not. There was no change in T1 relaxation values of lesions or T2 lesion volume over time. All patients remained clinically stable.

CONCLUSIONS

These results demonstrate that brain volume loss in MS is primarily driven by gray matter changes and may be independent of clinically effective treatment.

Disease-Modifying Therapies for Relapsing-Remitting and Primary Progressive Multiple Sclerosis: A Cost-Utility Analysis

BACKGROUND

Several disease-modifying therapies (DMTs) treat relapsing-remitting multiple sclerosis (RRMS) and primary progressive multiple sclerosis (PPMS). Few comprehensive cost-effectiveness analyses exist in this area, particularly from a payer perspective, despite rapidly increasing prices of DMTs.

OBJECTIVE

We aimed to systematically compare cost effectiveness of all relevant DMTs for first-line treatment of RRMS, second-line treatment of RRMS, and first-line treatment of PPMS.

METHODS

We used a Markov model with health states based on Expanded Disability Status Score categories. Upon discontinuing first-line treatment, RRMS patients continued to second-line therapy then to supportive care, and PPMS patients moved directly to supportive care. Data was sourced from clinical trials and commercially and publicly available sources. The target population was treatment-naïve adults with RRMS or PPMS. We used a lifetime horizon from a US payer perspective, and compared DMTs for RRMS (first-line: dimethyl fumarate, glatiramer acetate, interferon β-1a, interferon β-1b, peginterferon β-1a, teriflunomide, natalizumab, fingolimod, and ocrelizumab; second-line: alemtuzumab, natalizumab, fingolimod, and ocrelizumab), ocrelizumab for PPMS, and supportive care. Outcome measures included total costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs).

RESULTS

For RRMS first-line therapy, ocrelizumab dominated the other DMTs with an ICER of US$166,338/QALY compared with supportive care. For RRMS second-line therapy, alemtuzumab dominated the other three DMTs, providing more QALYs for lower costs. For PPMS, ocrelizumab had an ICER of US$648,799/QALY compared with supportive care. Wide variability in results was observed in the probabilistic sensitivity analysis. Results were sensitive to the relative risk of progression and cost of DMTs.

CONCLUSIONS

Ocrelizumab would likely be cost effective as a first-line treatment for RRMS with a discounted price but was not cost effective for PPMS. Alemtuzumab dominated other options for second-line treatment of RRMS. Other DMTs were generally similar in terms of costs and health outcomes, providing health benefits compared to supportive care but with significant added costs. If drug prices were lowered, more DMTs could be cost effective.

Alemtuzumab CARE-MS II 5-year follow-up: Efficacy and safety findings

OBJECTIVE

To evaluate 5-year efficacy and safety of alemtuzumab in patients with active relapsing-remitting multiple sclerosis and inadequate response to prior therapy.

METHODS

In the 2-year Comparison of Alemtuzumab and Rebif Efficacy in Multiple Sclerosis (CARE-MS) II study (NCT00548405), alemtuzumab-treated patients received 2 courses (baseline and 12 months later). Patients could enter an extension (NCT00930553), with as-needed alemtuzumab retreatment for relapse or MRI activity. Annualized relapse rate (ARR), 6-month confirmed disability worsening (CDW; ≥1-point Expanded Disability Status Scale [EDSS] score increase [≥1.5 if baseline EDSS = 0]), 6-month confirmed disability improvement (CDI; ≥1-point EDSS decrease [baseline score ≥2.0]), no evidence of disease activity (NEDA), brain volume loss (BVL), and adverse events (AEs) were assessed.

RESULTS

Most alemtuzumab-treated patients (92.9%) who completed CARE-MS II entered the extension; 59.8% received no alemtuzumab retreatment. ARR was low in each extension year (years 3-5: 0.22, 0.23, 0.18). Through 5 years, 75.1% of patients were free of 6-month CDW; 42.9% achieved 6-month CDI. In years 3, 4, and 5, proportions with NEDA were 52.9%, 54.2%, and 58.2%, respectively. Median yearly BVL remained low in the extension (years 1-5: -0.48%, -0.22%, -0.10%, -0.19%, -0.07%). AE exposure-adjusted incidence rates in the extension were lower than in the core study. Thyroid disorders peaked at year 3, declining thereafter.

CONCLUSIONS

Alemtuzumab provides durable efficacy through 5 years in patients with an inadequate response to prior therapy in the absence of continuous treatment.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that alemtuzumab provides efficacy and slowing of brain atrophy through 5 years.

Clinical and radiological control of highly active relapsing-remitting multiple sclerosis with first-line natalizumab

A 33-year-old man with gait instability, weakness of the left lower extremity, decreased visual acuity in the left eye, and urgency and urine incontinence was diagnosed of relapsing-remitting multiple sclerosis. He was treated with natalizumab (300 mg intravenously every 4 weeks) as first-line therapy, which reached at 6 months a favorable clinical evolution and dramatic radiological improvement (T2-weighted lesion load decreased by 50% and no gadolinium-enhancing T1 lesions) sustained over the course of 8 years. This clinical case shows the efficacy of natalizumab in a real-world setting and, particularly, the sustained effect of this drug in the long term as demonstrated by persistent radiological improvement. Natalizumab can be considered as the treatment of choice in relapsing-remitting multiple sclerosis forms presenting with two relapses and gadolinium-enhancing (Gd+) lesions.

Timing of high-efficacy therapy in relapsing-remitting multiple sclerosis: A systematic review

BACKGROUND

Immunotherapy initiated early after first presentation of relapsing-remitting multiple sclerosis is associated with improved long-term outcomes. One can therefore speculate that early initiation of highly effective immunotherapies, with an average efficacy that is superior to the typical first-line therapies, could further improve relapse and disability outcomes. However, the most common treatment strategy is to commence first-line therapies, followed by treatment escalation in patients who continue to experience on-treatment disease activity. While this monitoring approach is logical, the current lack of effective regenerative or remyelinating therapies behoves us to consider high-efficacy treatment strategies from disease onset (including induction therapy) in order to prevent irreversible disability.

OBJECTIVE

In this systematic review, we evaluate the effect of high-efficacy immunotherapies at different stages of MS.

METHODS

A systematic review of literature reporting outcomes of treatment with fingolimod, natalizumab or alemtuzumab at different stages of MS was carried out.

RESULTS AND CONCLUSIONS

Twelve publications reporting relevant information were included in the systematic review. The literature suggests that treatment with high-efficacy immunotherapies is more potent in suppressing relapse activity when initiated early vs. with a delay after the MS diagnosis. The evidence reported for disability and MRI outcomes is inconclusive.

Considerations on long-term immuno-intervention in the treatment of multiple sclerosis: an expert opinion

INTRODUCTION

As management of multiple sclerosis (MS) requires life-long treatment with disease-modifying agents, any risks associated with long-term use should be considered when evaluating therapeutic options.

AREAS COVERED

Immune cells of the innate and adaptive immune systems play various roles in the pathogenesis of MS. MS therapies affect the immune system, each with a unique mode of action, and consequently possess different long-term safety profiles. Rare, but serious safety concerns, including an increased risk of infection and cancer, have been associated with immunosuppressant use. The risks associated with newer immunosuppressive agents, which target specific elements of MS disease pathophysiology, are not yet fully established as the duration of clinical trials is relatively short and post-marketing experience is limited. Non-immunosuppressants used to treat MS have well-defined safety profiles established over a large number of patient-years demonstrating them to be well-tolerated long-term treatment options. When considering the long-term use of disease-modifying agents for treating MS, classification as immunosuppressants or non-immunosuppressants can be useful when evaluating potential risks associated with chronic use.

EXPERT OPINION

A successful therapeutic strategy for any serious, chronic disease such as MS should weigh effectiveness versus long-term safety of available treatments.

Effectiveness and safety of natalizumab in real-world clinical practice: Review of observational studies

Clinical trials have shown that natalizumab is highly effective for treating relapsing forms of multiple sclerosis (MS). The purpose of this analysis was to conduct a targeted review of data from country-specific observational studies and registries of natalizumab-treated patients with relapsing MS in order to more fully investigate the longer-term effectiveness and safety of this disease-modifying therapy in real-world clinical practice settings. A PubMed search was conducted on March 13, 2014, using the terms (natalizumab AND multiple sclerosis) AND (observational OR registry OR post-marketing OR clinical practice). Only English-language papers that reported effectiveness (in terms of effects on relapses, disability progression, and magnetic resonance imaging findings) and/or safety results from studies were included. Data from 22 studies/registries were included. Annualized relapse rates decreased by 73%-94% from baseline across the studies, with improvement maintained for up to 5 years during natalizumab treatment. Natalizumab effectiveness was also demonstrated via assessment of disability progression (Expanded Disability Status Scale), radiological measures, and no-evidence-of-disease-activity measures (clinical, radiological, and overall). Results were similar among patient groups stratified by level of disease activity. Safety outcomes were consistent with natalizumab's known safety profile. Data from country-specific observational studies and registries varying in size and scope support the effectiveness and safety of natalizumab in a broad range of patients in clinical practice.

Epoch Analysis of On-Treatment Disability Progression Events over Time in the Tysabri Observational Program (TOP)

OBJECTIVE

To evaluate the effect of natalizumab on disability progression beyond 2 years of treatment in clinical practice.

METHODS

Analyses included the 496 relapsing-remitting multiple sclerosis (RRMS) patients among 5122 patients in the Tysabri Observational Program (TOP) who had completed 4 continuous years of natalizumab treatment and had baseline (study enrollment) and postbaseline Expanded Disability Status Scale (EDSS) assessments. Proportions of patients with 6-month or 12-month confirmed ≥1.0-point EDSS progression relative to baseline were compared in treatment months 1-24 and 25-48. Sensitivity analyses compared progression rates in months 13-24 and 25-36.

RESULTS

Baseline characteristics appeared similar between the overall TOP population (N = 5122), patients who had completed 4 years of natalizumab treatment (n = 469), and patients eligible to complete 4 years in TOP who had discontinued natalizumab after 2 years of treatment (n = 514). Among 4-year completers, the proportion of patients with 6-month and 12-month confirmed EDSS progression decreased between months 1-24 and 25-48 of natalizumab treatment by 42% (from 10.9% to 6.3%; p < 0.01) and 52% (from 9.5% to 4.6%; p < 0.01), respectively. Few patients had 6-month or 12-month confirmed EDSS progression in both epochs (0.6% and 0.2%, respectively). Between months 13-24 and 25-36 of treatment, the proportion of patients with 6-month and 12-month confirmed EDSS progression decreased by 60% (from 7.5% to 3.0%; p < 0.01) and 58% (from 6.7% to 2.8%; p < 0.01), respectively. Significant reductions in disability progression events between months 13-24 and 25-36 were also observed in relapse-free patients.

CONCLUSION

In this observational study, the disability progression rate decreased further beyond 2 years of natalizumab treatment. Patients who responded well and remained on continuous natalizumab therapy for over 4 years had sustained and potentially enhanced reductions in EDSS progression over time.

Natalizumab in multiple sclerosis: discontinuation, progressive multifocal leukoencephalopathy and possible use in children

In the early 1990s, attention was drawn to the migration of immune cells into the central nervous system via the blood-brain barrier. The literature showed that lymphocytes binding to the endothelium were successfully inhibited by an antibody against α4β1 integrin. These biological findings resulted in the development of a humanized antibody to α4 integrin - natalizumab (NTZ) - to treat multiple sclerosis (MS). Here, we provide a systematic review and meta-analysis on the efficacy and safety of natalizumab, trying to answer the question whether its use may be recommended both in adult and in pediatric age groups as standard MS treatment. Our results highlight the improvement of clinical and radiological findings in treated patients (p < 0.005), confirming NTZ efficacy. Nevertheless, if NTZ is shown to be efficient, further studies should be performed to evaluate its safety and to target the MS profile that could benefit from this treatment.

Natalizumab treatment in multiple sclerosis: the experience from two Brazilian MS centers

Objective Analyze the demographics, clinical characteristics, efficacy and safety of natalizumab treatment in Brazilian patients with multiple sclerosis (MS) followed up for at least 12 months, in two tertiary MS care centers in São Paulo.Method We evaluated the effect of natalizumab treatment on annualized relapse rate and disability progression in 75 patients with MS treated with natalizumab for at least 12 months. A subgroup analysis was performed to evaluate efficacy of natalizumab treatment in patients with Expanded Disability Status Scale (EDSS) ≤ 3.0 vs patients with EDSS > 3.Results Patients treated for at least one year with natalizumab showed a 91% reduction in aRR, as well and an improvement in neurological disability. The impact of natalizumab treatment was greater in patients with EDSS < 3.0. Overall, natalizumab was safe but one patient developed progressive multifocal leukoencephalopathy.Conclusion Natalizumab as a third line therapy is safe and efficacious, especially in patients with mild neurological disability.

Reduced cerebrospinal fluid concentrations of oxysterols in response to natalizumab treatment of relapsing remitting multiple sclerosis

BACKGROUND

Natalizumab therapy reduces inflammation and degeneration of the CNS in relapsing-remitting multiple sclerosis (RRMS). In cerebrospinal fluid (CSF) the concentration of 24S-hydroxycholesterol (24OHC) reflect neurodegeneration, whereas 27-hydroxycholesterol (27OHC) is dependent on the integrity of the blood-brain barrier (BBB).

OBJECTIVE

To measure the impact from natalizumab treatment on 24OHC and 27OHC concentrations in serum and CSF of RRMS.

METHODS

In serum and CSF obtained from 31 patients before and following 12 months of natalizumab treatment, 24OHC and 27OHC were analyzed by isotope-dilution mass spectrometry.

RESULTS

Natalizumab treatment reduced CSF-24OHC concentrations (p=0.002), CSF-27OHC concentrations (p=0.01) and serum-24OHC concentrations (p=0.029). There was no significant effect of the treatment on serum-27OHC concentrations. Serum concentrations of 24OHC correlated with Symbol Digit Modalities Test scores before (r=0.5, p=0.007) and after natalizumab treatment (r=0.403, p=0.033).

CONCLUSIONS

We showed for the first time that natalizumab treatment of RRMS reduced the concentrations of 24- and 27OHC in CSF, indicating reduced neurodegeneration and improved integrity of the BBB, respectively. Our results imply a role for serum 24OHC as a biomarker of cognition (visuo-spatial ability and processing speed) in RRMS.

Comparative efficacy of switching to natalizumab in active multiple sclerosis

OBJECTIVE

To compare treatment efficacy and persistence in patients who switched to natalizumab versus those who switched between glatiramer acetate (GA) and interferon-beta (IFNβ) after an on-treatment relapse on IFNβ or GA using propensity score matched real-world datasets.

METHODS

Patients included were registered in MSBase or the TYSABRI Observational Program (TOP), had relapsed on IFNβ or GA within 12 months prior to switching to another therapy, and had initiated natalizumab or IFNβ/GA treatment ≤6 months after discontinuing prior therapy. Covariates were balanced across post switch treatment groups by propensity score matching at treatment initiation. Relapse, persistence, and disability measures were compared between matched treatment arms in the total population (n = 869/group) and in subgroups defined by prior treatment history (IFNβ only [n = 578/group], GA only [n = 165/group], or both IFNβ and GA [n = 176/group]).

RESULTS

Compared to switching between IFNβ and GA, switching to natalizumab reduced annualized relapse rate in year one by 65-75%, the risk of first relapse by 53-82% (mean follow-up 1.7-2.2 years) and treatment discontinuation events by 48-65% (all P ≤ 0.001). In the total population, switching to natalizumab reduced the risk of confirmed disability progression by 26% (P = 0.036) and decreased the total disability burden by 1.54 EDSS-years (P < 0.0001) over the first 24 months post switch.

INTERPRETATION

Using large, real-world, propensity-matched datasets we demonstrate that after a relapse on IFNβ or GA, switching to natalizumab (rather than between IFNβ and GA) led to superior outcomes for patients in all measures assessed. Results were consistent regardless of the prior treatment identity.

Natalizumab-related anaphylactoid reactions in MS patients are associated with HLA class II alleles

Objectives:

We aimed to investigate potential associations between human leukocyte antigen (HLA) class I and class II alleles and the development of anaphylactic/anaphylactoid reactions in patients with multiple sclerosis (MS) treated with natalizumab.

Methods:

HLA class I and II genotyping was performed in patients with MS who experienced anaphylactic/anaphylactoid reactions and in patients who did not develop infusion-related allergic reactions following natalizumab administration.

Results:

A total of 119 patients with MS from 3 different cohorts were included in the study: 54 with natalizumab-related anaphylactic/anaphylactoid reactions and 65 without allergic reactions. HLA-DRB1*13 and HLA-DRB1*14 alleles were significantly increased in patients who developed anaphylactic/anaphylactoid reactions (p_M-H = 3 × 10⁻⁷; odds ratio [OR]_M-H = 8.96, 95% confidence interval [CI] = 3.40–23.64), with a positive predictive value (PPV) of 82%. In contrast, the HLA-DRB1*15 allele was significantly more represented in patients who did not develop anaphylactic/anaphylactoid reactions to natalizumab (p_M-H = 6 × 10⁻⁴; OR_M-H = 0.2, 95% CI = 0.08–0.50), with a PPV of 81%.

Conclusions:

HLA-DRB1 genotyping before natalizumab treatment may help neurologists to identify patients with MS at risk for developing serious systemic hypersensitivity reactions associated with natalizumab administration.

The Toronto Observational Study of Natalizumab in Multiple Sclerosis

Background:

Natalizumab is indicated for the treatment of relapsing multiple sclerosis (MS) with insufficient response to first-line disease-modifying therapy (DMT). We studied the efficacy of natalizumab for treatment of MS in a single centre observational design.

Methods:

A retrospective observational study of 146 patients [66% female; mean age 37.4; 72% relapsing remitting MS (RRMS), 28% secondary progressive MS (SPMS)] referred for natalizumab treatment at St. Michael's Hospital MS Clinic between 2007 and August 2009. Data included demographic, clinical (Expanded Disability Status Scale (EDSS) and annualized relapse rate (ARR)) and patient self-report measures.

Results:

The mean duration of treatment was 20 months in those treated with natalizumab and 97% had received prior DMTs. Eighty-three patients (57%) received at least 12 months of natalizumab treatment. In those who received at least 12 months of treatment, baseline ARR and EDSS were 1.6 and 2.7 in RRMS patients versus 1.0 and 5.4 in SPMS with relapses. The ARR decreased with natalizumab treatment to 0.38 (76% reduction, p<0.001) in RRMS versus 0.32 in SPMS patients (68% reduction, p=0.01). There was a treatment associated 11% reduction in EDSS to 2.4 (p=0.04) in RRMS, but no significant change in SPMS. Eighty-five percent of patients reported improved overall quality of life (QOL) and 62% indicated improved energy.

Conclusions:

There was a major reduction in relapse rate, stabilization in EDSS and improvement in QOL and energy in some patients on natalizumab, all similar to treatment effects in the pivotal trial.

Radiologic MS disease activity during natalizumab treatment interruption: findings from RESTORE

The objective of this study is to characterize the timing and extent of radiologic MS disease recurrence during the 24-week natalizumab treatment interruption period in RESTORE. RESTORE was a randomized, partially placebo-controlled exploratory study. Natalizumab-treated patients with no gadolinium-enhancing (Gd+) lesions at screening (n = 175) were randomized 1:1:2 to continue natalizumab (n = 45), switch to placebo (n = 42), or switch to other therapies (n = 88) for 24 weeks. MRI assessments were performed every 4 weeks. Predictors of increased numbers of Gd+ lesions during natalizumab treatment interruption were evaluated. The numbers of Gd+ lesions were compared with retrospectively collected pre-natalizumab MRI reports and data from placebo-treated patients from two historical randomized clinical trials. Gd+ lesions were detected in 0 % (0/45) of natalizumab patients, 61 % (25/41) of placebo patients, and 48 % (39/81) of other-therapies patients during the randomized treatment period. Gd+ lesions were detected starting at week 12; most were observed at week 16 or later. Thirteen percent (14/107) of patients had >5 Gd+ lesions on ≥1 (of 6) scans during the randomized treatment period versus 7 % (7/107) of patients pre-natalizumab (based on medical record of a single scan). Younger patients and those with more Gd+ lesions pre-natalizumab were more likely to have increased MRI activity. Distribution of total and persistent Gd+ lesions in RESTORE patients was similar to placebo-treated historical control patients. In most patients, recurring radiological disease activity during natalizumab interruption did not exceed pre-natalizumab levels or levels seen in historical control patients.

Extended interval dosing of natalizumab: a two-center, 7-year experience

BACKGROUND

The enthusiasm for natalizumab, a highly efficacious agent in the treatment of multiple sclerosis (MS), has been tempered by the risks of progressive multifocal leukoencephalopathy associated with its use, and strategies to minimize those risks are of great interest. Extended interval dosing (EID) has been proposed as a way to maintain the efficacy of natalizumab while reducing exposure to it. We reviewed a cohort of patients who received natalizumab at 6-8-week intervals instead of the typical infusions every 4 weeks with the goal to assess if patients on EID had an increase in clinical relapses.

METHODS

This is a retrospective review of all patients with MS treated with natalizumab at two MS centers where patients were offered the opportunity to switch to an EID every 6 or 8 weeks.

RESULTS

A total of 361 patients received natalizumab for 22 ± 13 months (minimum duration 6 months). Of these, 96 patients received EID natalizumab at some point for 20 ± 11 months (minimum duration 6 months). Over the study period, there was no significant difference between the relapse rate in the monthly dosing (13%) and the EID (13%) groups of patients.

CONCLUSION

Natalizumab is effective in controlling MS as very few clinical relapses were observed in our dataset. We found that EID did not compromise the treatment effect as measured by relapse rate and no significant breakthrough disease activity was observed. EID is an optional regimen for maintenance natalizumab therapy, but prospective studies are warranted to determine its efficacy.

Safety and efficacy of natalizumab in Belgian multiple sclerosis patients: subgroup analysis of the natalizumab observational program

Natalizumab (Tysabri(®)) is highly efficacious in controlling disease activity in relapsing multiple sclerosis (MS) patients. As it is one of the more recent therapies for MS, there remains a need for long-term safety and efficacy data of natalizumab in a clinical practice setting. The Tysabri observational program (TOP) is an open-label, multicenter, multinational, prospective observational study, aiming to recruit up to 6,000 patients with relapsing-remitting MS from Europe, Canada and Australia. The objectives of this study are to collect long-term safety and efficacy data on disease activity and disability progression. We report here the interim results of the 563 patients included in TOP between December 2007 and 2012 from Belgium. This patient cohort was older at baseline, had longer disease duration, higher neurological impairment, and a higher baseline annualized relapse rate, when compared to patients included in the pivotal phase III AFFIRM trial. Nevertheless, the efficacy of natalizumab was comparable. The annualized relapse rate on treatment was reduced by 90.70 % (p < 0.0001) with a cumulative probability of relapse of 26.87 % at 24 months. The cumulative probabilities of sustained disability improvement and progression at 24 months were 25.68 and 9.01 %, respectively. There were no new safety concerns over the follow-up period. Two cases of progressive multifocal leukoencephalopathy were diagnosed. Our results are consistent with other observational studies in the post-marketing setting.

Clinical baseline factors predict response to natalizumab: their usefulness in patient selection

Background

Optimal patient selection would improve the risk-benefit ratio of natalizumab treatment for relapsing-remitting multiple sclerosis (RR MS). Clinical features of subjects responding to natalizumab have not been univocally recognized.

Methods

Longitudinal data on RR MS patients treated with natalizumab in Liguria, Italy are reported. Predictors of relapse occurrence and disability improvement were analyzed with a logistic regression method in subjects treated for one year (N = 62). A new score, called “Better EDSS Trend (BET)”, was devised to describe the impact of the treatment on disability. Changes in annualized relapse rate (ARR) and Expanded Disability Status Scale (EDSS) after one and two years and proportion of disease-free patients were evaluated.

Results

Previous EDSS worsening plus ARR ≥ 2 increased the risk of relapse during the treatment [Odds Ratio (OR) 4.12, P = 0.04], but this was not associated with an increase in disability at one year. EDSS 3.0-3.5 or high disease activity were associated with neurological improvement in the first year of treatment (respectively OR 5.78, P = 0.05 and OR 4.80, P = 0.05). Positive BET score, i.e. improvement in the disability trend, was observed in 40.3% of patients, and correlated with high ARR in the year before treatment (OR 1.69, P = 0.03).

Conclusion

Subjects with EDSS 3.0-3.5 and those with very active disease in the year before treatment are most likely to improve in neurological function under natalizumab. A relapse in the first year of treatment is associated to high pre-treatment disease activity; however, since the occurrence of a relapse did not have a negative impact on clinical improvement at one year, we suggest that it should not lead to treatment discontinuation. We propose BET as an additional endpoint of treatment response in MS.

Long-term management of natalizumab discontinuation in a large monocentric cohort of multiple sclerosis patients

BACKGROUND

Pivotal and post-marketing studies demonstrated the impressive efficacy and the good tolerability profile of natalizumab in Multiple Sclerosis patients. On the other hand long-term safety of natalizumab therapy is burdened by the risk of progressive multifocal leukoencephalopathy, especially in anti-JCV seropositive patients treated for more than two years. Some of these patients must stop the drug at the risk of disease reactivation.

OBJECTIVES

To evaluate the effects of natalizumab discontinuation in a monocentric cohort of multiple sclerosis patients followed for a mean time of 22.4 months.

METHODS

One hundred and ten patients, who stopped therapy after at least 12 infusions, were followed with periodic clinical and magnetic resonance imaging evaluations. One hundred patients started either immunomodulant therapy (n=90) or fingolimod (n=10) while 10 remained without any drug.

RESULTS

"Disease-activity free" patients were 25% at one year after discontinuation and annualized relapse rate significantly increased from 0.06 to 0.84 (p<0.0001). We found that the risk of reactivation peaked despite alternative treatments between the second and the eighth month after suspension, a so-called "high risk period". During this period the majority of patients showed a return to pre-natalizumab disease activity while 10% of patients presented a "rebound activity". A higher pre-natalizumab disease activity was correlated with an increased risk of reactivation (p=0.004).

CONCLUSIONS

Our data suggest that disease reactivation peaked during a "high risk period" between the second and the eighth month since stopping the drug. During this period no alternative treatments seemed to provide an adequate protection from disease reactivation. Though transient, this phase could be potentially dangerous, therefore we need to develop more effective strategies to deal with this challenge.

Natalizumab Treatment in Multiple Sclerosis Patients: A Multicenter Experience in Clinical Practice in Italy

We evaluated efficacy of natalizumab in relapsing-remitting multiple sclerosis patients in a clinical practice setting. We report data on the first consecutive 343 patients receiving natalizumab in 12 multiple sclerosis (MS) Italian centers enrolled between April 2007 and November 2010. The main efficacy endpoints were the proportion of patients free from relapses, disease progression, combined clinical activity, defined as presence of relapse or disease progression, from MRI activity, and from any disease activity defined as the absence of any single or combined activity. At the end of follow-up, the cumulative proportion of patients free from relapses was 68%; the proportion of patients free from Expanded Disability Status Scale (EDSS) progression was 93%; the proportion of patients free from combined clinical activity was 65%; the proportion of patients free from MRI activity was 77%; and the proportion of patients free from any disease activity was 53%. Natalizumab was effective in reducing clinical and neuroradiological disease activity. Its effectiveness in clinical practice is higher than that reported in pivotal trials and was maintained over time.

Spanish consensus on the use of natalizumab (Tysabri®)-2013

INTRODUCTION

Natalizumab treatment has been shown to be very efficacious in clinical trials and very effective in clinical practice in patients with relapsing-remitting multiple sclerosis, by reducing relapses, slowing disease progression, and improving magnetic resonance imaging patterns. However, the drug has also been associated with a risk of progressive multifocal leukoencephalopathy (PML). The first consensus statement on natalizumab use, published in 2011, has been updated to include new data on diagnostic procedures, monitoring for patients undergoing treatment, PML management, and other topics of interest including the management of patients discontinuing natalizumab.

MATERIAL AND METHODS

This updated version followed the method used in the first consensus. A group of Spanish experts in multiple sclerosis (the authors of the present document) reviewed all currently available literature on natalizumab and identified the relevant topics would need updating based on their clinical experience. The initial draft passed through review cycles until the final version was completed.

RESULTS AND CONCLUSIONS

Studies in clinical practice have demonstrated that changing to natalizumab is more effective than switching between immunomodulators. They favour early treatment with natalizumab rather than using natalizumab in a later stage as a rescue therapy. Although the drug is very effective, its potential adverse effects need to be considered, with particular attention to the patient's likelihood of developing PML. The neurologist should carefully explain the risks and benefits of the treatment, comparing them to the risks of multiple sclerosis in terms the patient can understand. Before treatment is started, laboratory tests and magnetic resonance images should be available to permit proper follow-up. The risk of PML should be stratified as high, medium, or low according to presence or absence of anti-JC virus antibodies, history of immunosuppressive therapy, and treatment duration. Although the presence of anti-JC virus antibodies is a significant finding, it should not be considered an absolute contraindication for natalizumab. This update provides general recommendations, but neurologists must use their clinical expertise to provide personalised follow-up for each patient.

Treatment options for patients with multiple sclerosis who have a suboptimal response to interferon-β therapy

BACKGROUND AND PURPOSE

Although the first-line disease-modifying therapies (DMTs) interferon beta and glatiramer acetate have a favourable benefit-to-risk profile, they are only partially effective for treating relapsing-remitting multiple sclerosis (RRMS). The optimization of treatment in patients who do not show a maximum response to first-line therapy is critical for achieving the best long-term outcomes. Treatment strategies for patients with a suboptimal response include switching to another first-line DMT or a second-line DMT. Natalizumab and fingolimod are approved for RRMS with high disease activity in the European Union and Canada.

METHODS

A comprehensive literature search for articles published between 1990 and April 2012 was undertaken.

RESULTS

This review discusses key clinical and safety data for fingolimod and natalizumab, particularly in the patient subgroups for whom these treatments are approved. Benefit-to-risk profiles, including first-dose cardiovascular effects associated with fingolimod and the risk of progressive multifocal encephalopathy with natalizumab, are discussed.

CONCLUSION

A descriptive comparison of fingolimod and natalizumab is provided in the context of the decision-making process of how and when to switch patients who have a suboptimal response to first-line therapy.

Natalizumab inhibits the expression of human endogenous retroviruses of the W family in multiple sclerosis patients: a longitudinal cohort study

Background:

Several viruses were reported as co-factors triggering the pathogenesis of multiple sclerosis (MS), including the endogenous retroviruses of the HERV-W family, that were also proposed as biomarkers of disease progression and therapy outcome.

Objective:

The objective of this article is to clarify whether in MS patients treatment with natalizumab has effects on MSRV/syncytin-1/HERV-W expression and the possible relationship with disease outcome.

Methods:

Peripheral blood mononuclear cells were collected from 22 patients with relapsing–remitting disease, at entry and after three, six and 12 months of treatment with natalizumab. The cell subpopulations and the expression of MSRV env/syncytin-1/HERV-W env were analyzed by flow cytometry and by discriminatory env-specific RT-PCR assays.

Results:

By flow cytometry the relative amounts of T, NK and monocyte subpopulations were shown to remain fairly constant. A relative increase of B lymphocytes was observed at three to six months ( p = 0.033). The MSRV env and syncitin-1 transcripts were reduced at six to 12 months of therapy ( p = 0.0001). Accordingly, at month 12, the plasma-membrane levels of the HERV-W env protein were reduced ( p = 0.0001). B cells, NK and monocytes but not T cells expressed the HERV-W env protein. None of the patients relapsed during therapy.

Conclusion:

Effective therapy with natalizumab downregulates MSRV/syncytin-1/HERV-W expression.

Best practice in the use of natalizumab in multiple sclerosis

Natalizumab is approved for the treatment of patients with relapsing-remitting multiple sclerosis who have failed first-line treatment with traditional disease-modifying therapies or who have highly active disease. The drug has proved highly effective, both in a clinical trial setting and in clinical practice, with marked reductions in the rate of clinical relapses and slowed disease progression. These clinical outcomes are mirrored by a marked reduction in disease activity as evidenced by magnetic resonance imaging of the brain. However, natalizumab treatment has been associated with a risk of progressive multifocal leukoencephalopathy (PML), a potentially fatal condition caused by JC virus (JCV) activation. When this condition was detected in a clinical trial shortly after approval, the drug was immediately and voluntarily withdrawn from the market. As a condition of its reinstatement, stringent pharmacovigilance measures and a risk management plan were enforced. The recent availability of a two-step enzyme-linked immunosorbent assay (ELISA) test for the presence of anti-JCV antibodies (free testing is available in a central laboratory for registered centers), along with an ever-improving understanding of other risk factors such as prior immunosuppressant use and duration of treatment, allow an increasingly refined stratification of the risk of PML. This improved stratification of risk can help guide decisions about treatment. This review will also deal with other topics of relevance to clinical practice such as the development of antinatalizumab antibodies and their negative implications in terms of hypersensitivity reactions and loss of efficacy, withdrawal of treatment, and compassionate pediatric use.

Natalizumab treatment of multiple sclerosis in Spain: results of an extensive observational study

Natalizumab has been shown to be effective in pivotal clinical trials in multiple sclerosis; however, the patients in whom treatment is indicated in clinical practice have a different clinical profile from those included in the clinical trials. The aim of this study is therefore to collect data on natalizumab use in everyday clinical practice in Spain. The 86 participating centers throughout Spain submitted data on disease characteristics at baseline and after treatment. Valid data were available for 1,364 patients (69.3% women, 86.9% with relapsing–remitting disease).

Early brain pseudoatrophy while on natalizumab therapy is due to white matter volume changes

Background:

Investigation of atrophy data from a pivotal natalizumab trial has demonstrated an increased rate of volume loss, compared to placebo, after the first year of therapy. It was considered to be probably due to a pseudoatrophy effect.

Objective:

To assess grey and white matter volume changes and their relation to global brain volume changes and to baseline inflammation, for patients under natalizumab therapy.

Methods:

We selected 45 patients on natalizumab therapy for at least 24 months, with magnetic resonance imaging (MRI) scans at baseline, 12 and 24 months. We calculated the percentage brain volume change (PBVC) for the first and second year, using SIENA software. Grey and white matter fractions (GMF and WMF, respectively) for the first year were calculated with SPM5, using lesion masks. After quality checks, six patients were excluded. We studied the predictive variables of change in brain volumes.

Results:

The PBVC decrease was faster during the first year (−1.10% ± 1.43%), as compared to the second (−0.51% ± 0.96%) ( p = 0.037). These differences were more marked in patients with baseline gadolinium-enhancing lesions ( p = 0.005). Mean GMF and WMF changes during the first year of treatment were +1.15% (n.s.) and −1.72% ( p = 0.017), respectively. The presence of active lesions at baseline MRI predicted PBVC ( p = 0.022) and WMF change ( p = 0.026) during the first year of treatment, after adjusting for age and corticosteroid treatment. No predictors were found for GMF volume changes.

Conclusion:

Early brain volume loss during natalizumab therapy is mainly due to WMF volume loss and it is related to the inflammatory activity present at the onset of therapy. We found that the pseudoatrophy effect is mostly due to white matter volume changes.

Clinical effects of natalizumab on multiple sclerosis appear early in treatment course

In clinical practice natalizumab is typically used in patients who have experienced breakthrough disease during treatment with interferon beta (IFNβ) or glatiramer acetate. In these patients it is important to reduce disease activity as quickly as possible. In a phase II study, differences between natalizumab and placebo in MRI outcomes reflecting inflammatory activity were evident after the first infusion and maintained through a 6-month period, suggesting a rapid onset of natalizumab treatment effects. To explore how soon after natalizumab initiation clinical effects become apparent, annualized relapse rates per 3-month period and time to first relapse were analyzed in the phase III AFFIRM study (natalizumab vs. placebo) and in the multinational Tysabri^® Observational Program (TOP). In AFFIRM, natalizumab reduced the annualized relapse rate within 3 months of treatment initiation compared with placebo in the overall population (0.30 vs. 0.71; p < 0.0001) and in patients with highly active disease (0.30 vs. 0.94; p = 0.0039). The low annualized relapse rate was maintained throughout the 2-year study period, and the risk of relapse in AFFIRM patients treated with natalizumab was reduced [hazard ratio against placebo 0.42 (95 % CI 0.34–0.52); p < 0.0001]. Rapid reductions in annualized relapse rate also occurred in TOP (baseline 1.99 vs. 0–3 months 0.26; p < 0.0001). Natalizumab resulted in rapid, sustained reductions in disease activity in both AFFIRM and in clinical practice. This decrease in disease activity occurred within the first 3 months of treatment even in patients with more active disease.

Predictors of freedom from disease activity in natalizumab treated-patients with multiple sclerosis

PURPOSE

To identify baseline predictors of the response to natalizumab in patients with relapsing-remitting multiple sclerosis (RRMS).

METHODS

We prospectively collected clinical and magnetic resonance imaging (MRI) data of RRMS patients treated with natalizumab and followed-up for 24 months. They were categorized according to different outcomes of response to natalizumab: (i) "full" responders, i.e. those having no relapses, no sustained disability worsening on Expanded Disability Status Scale (EDSS), and no MRI activity; (ii) "partial" responders, i.e. those having MRI activity, but not relapses and/or EDSS worsening; and (iii) "poor" responder, i.e. those experiencing relapses and/or EDSS worsening.

RESULTS

We analysed data of 210 RR-MS patients (147 F, 63 M); at the end of the 24-month study period, 120 (57.1%), 36 (17.1%), and 54 (25.8%) patients were defined as "full", "partial" or "poor" responders, respectively. Thirty-two (89%) patients classified as "partial" responders experienced MRI activity at the 6-month scan; the majority of them had >2 contrast-enhancing lesions at baseline MRI scan or >2 relapses in the year prior to starting therapy. A "full" response to natalizumab was found more likely in patients with ≤ 2 relapses in the year prior to treatment start (OR=3.68; p=0.002), and in those with an EDSS score ≤ 2.5 at baseline (OR=3.60; p<0.001). Accordingly, patients with >2 relapses in the year prior to treatment start, or those with an EDSS score ≥ 3.0 at baseline were more likely to be classified as "poor responders". These figures were replicated even after excluding 20 patients who developed anti-natalizumab antibodies.

CONCLUSION

Our results suggest that natalizumab may lead to a complete remission of MS if started in patients with less aggressive disease (i.e. few relapses and mild disability), thus suggesting its possible role as first switching option, or even first-line therapy, at least in JCV-negative patients. We also support the recommendation against an immediate discontinuation of despite the occurrence of MRI activity in the first few months of treatment, since the freedom from clinical disease activity could be still achieved.

A genetic variant of the anti-apoptotic protein Akt predicts natalizumab-induced lymphocytosis and post-natalizumab multiple sclerosis reactivation

Background:

Multiple sclerosis (MS) patients discontinuing natalizumab treatment are at risk of disease reactivation. No clinical or surrogate parameters exist to identify patients at risk of post-natalizumab MS reactivation.

Objective:

To determine the role of natalizumab-induced lymphocytosis and of Akt polymorphisms in disease reactivation after natalizumab discontinuation.

Methods:

Peripheral leukocyte count and composition were monitored in 93 MS patients during natalizumab treatment, and in 56 of these subjects who discontinued the treatment. Genetic variants of the anti-apoptotic protein Akt were determined in all subjects because natalizumab modulates the apoptotic pathway and lymphocyte survival is regulated by the apoptotic cascade.

Results:

Natalizumab-induced peripheral lymphocytosis protected from post-natalizumab MS reactivation. Subjects who relapsed or had magnetic resonance imaging (MRI) worsening after treatment cessation, in fact, had milder peripheral lymphocyte increases during the treatment, largely caused by less marked T cell increase. Furthermore, subjects carrying a variant of the gene coding for Akt associated with reduced anti-apoptotic efficiency (rs2498804T) had lower lymphocytosis and higher risk of disease reactivation.

Conclusion:

This study identified one functionally meaningful genetic variant within the Akt signaling pathway that is associated with both lymphocyte count and composition alterations during natalizumab treatment, and with the risk of disease reactivation after natalizumab discontinuation.

Change in the clinical activity of multiple sclerosis after treatment switch for suboptimal response

BACKGROUND

  Therapy for multiple sclerosis (MS) has a partial efficacy, and a significant proportion of treated patients will develop a suboptimal response with first-line disease-modifying drugs (DMD). Therapy switch in patients with MS can be a strategy after a treatment failure. We studied the change in clinical activity after switching of first-line DMD because of a treatment failure.

METHODS

  Relapsing-remitting multiple sclerosis (RRMS) patients treated with interferon-beta (IFNB) or glatiramer acetate (GA) were divided into (i) patients without change in DMD, (ii) patients with a change in DMD because of a poor response, and (iii) those with a change in DMD without relation with response. Annualized relapse rate (ARR) and relapse-free proportions were analyzed.

RESULTS

  We identified 923 patients with RRMS. Of the 180 who experienced a change because of suboptimal response, 90 switched to another first-line DMT, 38 to mitoxantrone, and 52 to natalizumab. Median ARR in the pre-DMD period on first DMD and second DMD was the following: 1, 1, and 0 for switchers from IFNB to another IFNB (P = 0.0001); 0.67, 1, and 0 for switchers from GA to IFNB (P = 0.01); 1, 1, and 0 for switchers from an IFNB to GA (P = 0.02); 1.1, 1.5, 0.2 for switchers from IFNB or GA to mitoxantrone (P = 0.0001); 0.9, 1, 0 for switchers from IFNB or GA to natalizumab (P = 0.0001).

CONCLUSIONS

  In patients with RRMS who have a poor response, switch to another DMD may reduce the clinical activity of the disease.

Long-term risk of leukaemia or cardiomyopathy after mitoxantrone therapy for multiple sclerosis

BACKGROUND

Mitoxantrone has been extensively used as a disease-modifying therapy for multiple sclerosis. However, estimates of the associated risk of therapy-related acute leukaemia and cardiomyopathy have been derived from short-term studies. This study aimed to ascertain the long-term risk of therapy-related acute leukaemia or cardiomyopathy after mitoxantrone therapy for multiple sclerosis.

METHODS

Between 2002 and 2010, 50 patients were treated with mitoxantrone at a single centre using a standard protocol (12 mg/m(2) body surface area monthly for 6 months as tolerated to a maximum of 72 mg/m(2) body surface area). Follow-up haematologic and echocardiographic data were collected in March 2011.

RESULTS

Fifteen patients (30%) were excluded from analysis either because of lack of follow-up data, death due to non-cardiac and non-haematologic causes, or comorbid cardiovascular disease. The remaining 35 patients (70%) were followed for a median of 75 months (range: 9-103). The median cumulative mitoxantrone dose given was 72 mg/m(2) body surface area (range: 24-123). At the end of follow-up, no patients had developed therapy-related acute leukaemia. One patient suffered an asymptomatic drop in left ventricular ejection fraction from 55 to 47%.

CONCLUSION

This series of patients followed for up to 8.5 years suggests that the risk of either therapy-related acute leukaemia or cardiomyopathy after mitoxantrone therapy for multiple sclerosis is low when patients are treated within standard protocol.