Safety and efficacy of dimethyl fumarate in multiple sclerosis: a multi-center observational study.

Dimethyl fumarate (DMF) was recently approved for treating patients with relapsing-remitting multiple sclerosis (RRMS) based on two phase III clinical trials demonstrating its efficacy. This prompts the need for demonstrating the clinical efficacy and safety of DMF in the real world. By retrospective analysis of medical records at two German MS centers, 644 MS patients treated with DMF were identified. All were included in a safety analysis, and a subgroup of patients with available efficacy data during previous MS therapies (n = 352) was further analyzed for annualized relapse rate and disability progression assessed by the EDSS. In the overall DMF population studied, the annualized relapse rate decreased from 0.52 at baseline to 0.35, and the annualized disability progression from 0.15 to 0.10. Patients who were switched from interferons or glatiramer acetate to DMF revealed a greater benefit, whereas patients pretreated with more potent immunotherapies did not respond that well. Interestingly, patients with a lymphocyte count ≥2000/µl after 0.52 years (mean, SD 0.2) of DMF treatment did not benefit compared to those with lower lymphocyte counts. In total, 22.2 % of the patients withdrew from DMF due to side effects, with gastrointestinal discomfort (12.7 %) and lymphopenia (5.3 %) as most frequently reported reasons. Our study corroborates that DMF is an overall safe and effective drug that reduces relapse rate as well as disability progression in MS patients. Further prospective studies are warranted to establish the additional parameters predicting DMF response, especially in patients switching from other first-line immunotherapies.

[Pegylated interferon beta 1a. A new therapy option for treatment of relapsing-remitting multiple sclerosis]. / Pegyliertes Interferon-beta 1a. Eine neue Therapieoption zur Behandlung der schubförmigen multiplen Sklerose.

Pegylation of pharmacological substances was developed in the 1970s as a way of improving their efficacy and elimination and hence reducing the dosage frequency. A prominent example is pegylation of IFNα, which revolutionized the treatment of virus hepatitis in the late 1990s. Efforts have now succeeded in producing a pegylated interferon beta (PEG-IFN-ß1a) to treat multiple sclerosis (MS) and the efficacy and safety have been investigated in a phase III trial called the ADVANCE study. The 1-year results of this randomized, double blind, multicenter, placebo-controlled study in more than 1500 MS patients show that administration of subcutaneous PEG-IFN-ß1a significantly reduces the annual relapse rate and disability progression. The safety and tolerability profile of PEG-IFN-ß1a was found to be similar to that of conventional IFN-ß drugs. The most common adverse events were flu-like symptoms and redness at the injection site. The results of this study underscore that PEG-IFN-ß1a is an interesting new therapeutic option in the treatment of relapsing-remitting MS that combines highly effective interferon with the established tolerability and safety profile of IFN-ß at a reduced dosage frequency.

Monomethylfumarate reduces in vitro migration of mononuclear cells.

Migration of immunocompetent cells into the central nervous system represents a key event in the immunopathogenesis of multiple sclerosis (MS). Fumaric acid esters have recently been approved for patients with MS. Their mode of action is not fully understood so far. We analyzed the effect of monomethylfumarate (MMF), the immediate metabolite of dimethylfumarate, on migration of lymphocytes and macrophages. Peripheral blood mononuclear cells (PBMCs) were isolated from patients with MS and healthy donors. PBMCs were treated with MMF in vitro and their migratory capacity was studied in a Boyden chamber assay. In addition, expression of matrix metalloproteinases (MMPs), chemokine receptors, adhesion molecules, and molecules of the oxidative stress cascade was assessed. MMF decreased the migratory capacity of T lymphocytes, but not of macrophages. Lymphocytes as well as macrophages responded to MMF by the upregulation of oxidative stress molecules; however, no effect was seen on the expression of MMPs, chemokine receptors, and adhesion molecules. There was no difference in comparison with cells from healthy controls. MMF reduces the migratory activity of lymphocytes most likely by changing their activational state. This points to a potential novel mode of action differentiating this drug from other available immunotherapies.

[Cannabinoids for symptomatic therapy of multiple sclerosis]. / Cannabinoide zur symptomatischen Therapie der Multiplen Sklerose.

Spasticity represents a common troublesome symptom in patients with multiple sclerosis (MS). Treatment of spasticity remains difficult, which has prompted some patients to self-medicate with and perceive benefits from cannabis. Advances in the understanding of cannabinoid biology support these anecdotal observations. Various clinical reports as well as randomized, double-blind, placebo-controlled studies have now demonstrated clinical efficacy of cannabinoids for the treatment of spasticity in MS patients. Sativex is a 1:1 mix of delta-9-tetrahydocannabinol and cannabidiol extracted from cloned Cannabis sativa chemovars, which recently received a label for treating MS-related spasticity in Germany. The present article reviews the current understanding of cannabinoid biology and the value of cannabinoids as a symptomatic treatment option in MS.

[Interferon ß for multiple sclerosis. How much is good enough?]. / Interferon ß bei Multipler Sklerose. Wie viel ist gut genug?

Interferon ß-1b (IFNB-1b, Betaferon®) was the first therapy for multiple sclerosis (MS) showing efficacy in a randomized controlled clinical trial. Early studies suggested a dose-dependency of the clinical efficacy of IFNB-1b. However, until recently no reliable clinical data were available to assess the potential of higher dosing to increase therapeutic efficacy. In addition, no clinical trials have been conducted to directly compare the efficacy of IFNB-1b with that of glatiramer acetate, an alternative first line treatment option for relapsing-remitting MS. Just recently, the prospective, randomized, multicenter study BEYOND was published which addressed both issues. In this review the BEYOND trial is reviewed and placed in the context of advantages and disadvantages of currently available first line therapies for MS.

[4-Aminopyridine (Fampridine). A new attempt for the symptomatic treatment of multiple sclerosis]. / 4-Aminopyridin (Fampridin). Ein neuer Ansatz zur symptomatischen Therapie der Multiplen Sklerose.

Mobility limitation is a frequent clinical symptom of multiple sclerosis (MS) that poses a therapeutic challenge. For years results of animal experiments and clinical experience have indicated that the potassium channel blocker 4-aminopyridine improves axonal excitatory circuits and thus muscular strength in demyelinating diseases. A recently conducted randomized, placebo-controlled, multicenter phase 3 clinical trial in MS patients was able to show that an oral sustained-release formulation of 4-aminopyridine (Fampridine-SR) represents a suitable agent for treatment of walking disability in MS patients.This overview presents the study data and discusses the value of 4-aminopyridine for the symptomatic treatment of MS as a neurofunctional modifier of this disabling disease.

Cladribine impedes in vitro migration of mononuclear cells: a possible implication for treating multiple sclerosis.

BACKGROUND: Damage of the blood-brain barrier and the migration of immunocompetent cells into the CNS represent key events in the immunopathogenesis of multiple sclerosis (MS). Cladribine is an immunosuppressive drug currently investigated in a phase-III clinical trial for relapsing-remitting MS. However, its precise mode of action remains elusive so far. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from five patients with MS and five healthy donors. PBMCs were treated with cladribine in vitro. The migratory capacity was studied in an in vitro Boyden chamber assay; cells and their rate of migration were analyzed by light microscopy and flow cytometry. RESULTS: Cladribine decreased the migratory capacity of CD14(+) monocytes, as well as of CD4(+) and CD8(+) T lymphocytes. T lymphocytes were affected more than monocytes. There was no difference in this effect when comparing mononuclear cells from MS patients with cells from healthy controls. CONCLUSIONS: Cladribine might achieve, at least in part, its clinical and paraclinical efficacy by inhibiting the migration of inflammatory cells into and within the CNS.

Superficial siderosis of the central nervous system: pathogenetic heterogeneity and therapeutic approaches.

OBJECTIVE: Superficial siderosis of the central nervous system (CNS) is a rare chronic progressive disorder caused by chronic subarachnoid hemorrhage. We present four patients with superficial siderosis of the CNS to describe the characteristic symptoms, and to discuss the pathogenetic heterogeneity and possible new therapeutic approaches. RESULTS: The causes of chronic subarachnoid bleeding in superficial siderosis were different. In two patients surgical treatment of ependymoma or cerebral cavernomas were the underlying diseases. No cause was detected in one patient. For the first time, we present one patient with vasculitis of the central nervous system associated with systemic hemochromatosis in superficial siderosis. Therapeutic approaches included exstirpation of cavernomas as the source of chronic bleeding in one patient, immunosuppressive therapy and venupunctures in the patient with vasculitis and hemochromatosis, and symptomatic treatment with chelating agents and antioxidants. The patients remained clinically stable for the follow-up period of up to 2 years. CONCLUSIONS: Our cases underline the pathogenetic heterogeneity of superficial siderosis and favor the early diagnosis for prompt initiation of therapy. Besides treatment of the underlying condition, antioxidants and radical scavengers may be effective in halting the progression of the disease.

Blockade of signaling via the very late antigen (VLA-4) and its counterligand vascular cell adhesion molecule-1 (VCAM-1) causes increased T cell apoptosis in experimental autoimmune neuritis.

We characterized the early effects of anti-very late antigen (VLA-4) and its counterligand vascular cell adhesion molecule-1 (VCAM-1) antibody therapy on T cell infiltration and apoptosis in adoptive transfer experimental autoimmune neuritis of female Lewis rats. At the peak of disease, animals were treated with anti-VCAM-1 monoclonal antibody (mAb), anti-VLA-4 mAb, or the respective isotype mAb controls 18, 12, or 6 h before perfusion. Anti-VCAM-1 led to a rapid, significant increase of apoptotic T cells in the sciatic nerve with a maximum after 6 h, preceding the significant decrease of T cell infiltration seen after 18 h. This was accompanied by a significant reduction in mRNA levels for IFN-gamma and inducible nitric oxide synthase. The results for anti-VLA-4 treatment showed a similar trend. The early increase of T cell apoptosis following disruption of VLA-4/VCAM-1 interaction may reflect a novel signaling component of proapoptotic pathways.

High-dose methylprednisolone therapy in multiple sclerosis induces apoptosis in peripheral blood leukocytes.

BACKGROUND: Apoptosis is supposed to contribute to the elimination of T cells from the inflamed central nervous system in the natural disease course of multiple sclerosis (MS). In the animal model experimental autoimmune encephalomyelitis, T-cell apoptosis can be induced by high-dose glucocorticoid (GC) administration. OBJECTIVE: To study the effects of intravenous high-dose GC therapy in MS on T-cell apoptosis ex vivo. PATIENTS: Sixty-six patients with MS (28 with relapsing-remitting MS, 22 with secondary chronic progressive MS, and 16 with primary chronic progressive MS) and 16 control patients receiving corticosteroids for other disorders were included in the study. METHODS: Blood samples were collected before and immediately after the first infusion of 500 to 1000 mg of methylprednisolone given during 2 hours in the early morning. Gradient-isolated peripheral blood leukocytes (PBLs) were cultured, unstimulated, with corticosteroids (positive control), the mitogen phytohemagglutinin, or anti-T-cell receptor monoclonal antibody. For investigation of apoptosis, PBLs were cultured overnight and analyzed by immunoflow cytometry using TUNEL (terminal transferase-mediated dUTP biotin nick end labeling) or annexin labeling in combination with CD4, CD8, CD22, CD56, or bcl-2 staining. Proliferation was measured by (3)H-thymidine incorporation. For cytokine determination, supernatants were collected after 48 hours of culture. RESULTS: After in vivo corticosteroid treatment, apoptosis of unstimulated PBLs was markedly and significantly augmented in all 3 MS subgroups. Fluorescence-activated cell sorter analysis showed that apoptosis affected predominantly CD4 T cells. Natural killer cells showed a relative increase after GC therapy without a change in the rate of apoptotic cells. Expression of bcl-2 in T-cell subpopulations was not significantly modified by high-dose GC therapy. Culture supernatants of T-cell receptor-stimulated PBLs after GC therapy contained lower concentrations of interleukin 2, interferon gamma, and tumor necrosis factor alpha than those from PBLs taken before pulse therapy. Similar changes in the rate of apoptosis and cytokine production were seen in controls. CONCLUSIONS: Corticosteroid pulse therapy is a strong inducer of leukocyte apoptosis. Induction of apoptosis might contribute to the down-regulation of T-cell activity and thereby terminate inflammation in the central nervous system.