Tysabri

Natalizumab, a recombinant humanized monoclonal antibody directed against the α4 subunit of the integrins α4ß1 and α4ß7, has been approved for the treatment of active relapsing-remitting MS. Although natalizumab is a highly beneficial drug that effectively reduces the risk of sustained disability progression and the rate of clinical relapses, some patients do not respond to it, and some are at higher risk of developing progressive multifocal leukoencephalopathy (PML). The histopathological effects after natalizumab therapy are still unknown...

Background: Natalizumab (NAT) is a high-efficacy treatment for relapsing remitting multiple sclerosis (RRMS). However, it is associated with an increased risk of progressive multifocal leukoencephalopathy that sometimes requires treatment cessation with a risk of returning disease activity. The aim of this study was to characterize the pharmacokinetics and -dynamics as well as neurodestruction marker serum neurofilament light chain (sNfL) in patients with RRMS and secondary progressive MS (SPMS) stopping NAT in correlation to clinical data...

We report a case of a previously well, 25-year-old Caucasian female whose diagnosis of multiple sclerosis (MS) followed significant trauma. Her symptoms and signs developed quickly and satisfied the criteria for rapidly evolving relapsing-remitting MS. She was started on natalizumab (Tysabri) and was stabilized. We discuss the existing literature on traumatic demyelination and possible underlying mechanisms.

This article presents a simplified view of integrins with emphasis on the α4 (α4β1/VLA-4) integrin. Integrins are heterodimeric proteins expressed on the cell surface of leukocytes that participate in a wide variety of functions, such as survival, growth, differentiation, migration, inflammatory responses, tumour invasion, among others. When the extracellular matrix is degraded or deformed, cells are forced to undergo responsive changes that influence remodelling during physiological and pathological events...

The α4ß7 integrin is upregulated on naive and memory T cell subsets in patients who subsequently develop gastrointestinal (GI) acute GVHD. Natalizumab (Tysabri® , Biogen Inc.) acts against the α4 subunit that mediates homing of lymphocytes to the GI tract. We initiated a phase II study of natalizumab with corticosteroids for initial treatment of acute GI GVHD. In total, 300 mg IV of natalizumab was given, with steroids initiated up to 3 days prior. Twenty-one subjects were treated, median age was 63 years (range 38-74), and 15 (71%) were male...

BACKGROUND: Central nervous system damage in multiple sclerosis (MS) is responsible for serious deficiencies. Current therapies are focused on the treatment of inflammation; however, there is an urgent need for innovative therapies promoting neuroregeneration, particularly myelin repair. It is demonstrated that testosterone can act through neural androgen receptors and several clinical observations stimulated an interest in the potential protective effects of testosterone treatment for MS...

BACKGROUND: Natalizumab has been associated with disability improvement as indicated by a confirmed Expanded Disability Status Scale (EDSS) score decrease. OBJECTIVE: The aim of this study was to characterize disability improvement in patients in the Tysabri Observational Program (TOP), an ongoing observational study of relapsing-remitting multiple sclerosis patients initiating natalizumab in clinical practice. METHODS: TOP data as of November 2018 were included...

Drug resistance is an obstacle in the therapy of acute lymphoblastic leukemia (ALL). Whether the physical properties such as the motility of the cells contribute to the survival of ALL cells after drug treatment has recently been of increasing interest, as they could potentially allow the metastasis of solid tumor cells and the migration of leukemia cells. We hypothesized that chemotherapeutic treatment may alter these physical cellular properties. To investigate the motility of chemotherapeutics-treated B-cell ALL (B-ALL) cells, patient-derived B-ALL cells were treated with chemotherapy for 7 days and left for 12 h without chemotherapeutic treatment...

BACKGROUND: Natalizumab is a highly efficacious therapy for relapsing-remitting multiple sclerosis (RRMS). Patients who discontinue natalizumab may experience return of MS disease activity. OBJECTIVE: The aim of this study was to analyze predictors of post-natalizumab disease activity return. METHODS: The Tysabri® Observational Program (TOP) is an ongoing observational study of natalizumab-treated RRMS patients. Patients discontinuing natalizumab are encouraged to remain in TOP...

OBJECTIVE: The Tysabri Observational Programme (TOP), which began >10 years ago, is an open-label, multinational, prospective observational study evaluating the long-term safety and effectiveness of natalizumab in relapsing-remitting multiple sclerosis patients. METHODS: These data provide a 10-year interim analysis of safety and effectiveness in TOP. Annualised relapse rates (ARRs) and disability progression/improvement were analysed using the Poisson model and the Kaplan-Meier method, respectively...

Objective: To determine multiple sclerosis patient characteristics that predict a shorter duration of natalizumab treatment. Methods: The Tysabri Outreach: Unified Commitment to Health database was reviewed to identify patients treated with natalizumab at our centers. Cox proportional hazards models were used to evaluate patient characteristics associated with shorter treatment durations on natalizumab. Associations were also assessed with respect to specific reasons for stopping natalizumab...

The objective of the study was to obtain information on the toxicity of biosimilar natalizumab (PB006) in comparison to the reference product Tysabri® . Cynomolgus monkeys (15 males and 15 females), three animals per sex and group were treated with either PB006 or the reference product Tysabri® at dose levels of 3 or 30 mg/kg body weight or placebo by intravenous infusion every other day for a period of 4 weeks. The study is also meant to facilitate ethics committee approval in specific countries for the planned confirmatory efficacy and safety study in patients...

BACKGROUND: Natalizumab is an effective treatment for multiple sclerosis (MS) and has a well-characterized safety profile, with more than 10 years of postmarketing experience. TYGRIS was a 5-year observational cohort study designed to obtain long-term safety data in natalizumab-treated MS patients. We examined the incidence and pattern of serious adverse events (SAEs) in this large postmarketing sample of natalizumab-treated patients. METHODS: Investigators reported SAEs in natalizumab-treated patients...

OBJECTIVES: This article reports a study of cell mechanics in patient-derived (primary) B-cell acute lymphocytic leukemia (ALL) cells treated with antibodies against integrins. Leukemia cell adhesion to stromal cells mediates chemotherapeutic drug resistance, also known as cell adhesion-mediated chemotherapeutic drug resistance. We have previously shown that antibodies against integrin α4 and α6 adhesion molecules can de-adhere ALL cells from stromal cells or counter-receptors. Because drug-resistant cells are more deformable, as evaluated by single-beam acoustic tweezers, we hypothesized that changes in cell mechanics might contribute to the de-adhesive effect of integrin-targeting antibodies...

OBJECTIVE: To use the large dataset from the Tysabri Outreach: Unified Commitment to Health (TOUCH) program to compare progressive multifocal leukoencephalopathy (PML) risk with natalizumab extended interval dosing (EID) vs standard interval dosing (SID) in patients with multiple sclerosis (MS). METHODS: This retrospective cohort study included anti-JC virus antibody-positive patients (n = 35,521) in the TOUCH database as of June 1, 2017. The effect of EID on PML risk was evaluated with 3 planned analyses using Kaplan-Meier methods stratified by prior immunosuppressant use...

BACKGROUND: Multiple sclerosis (MS) patients represent a population potentially affected by the intracerebral accumulation of gadolinium-based contrast agents (GBCA) due to repeated magnetic resonance imaging (MRI) performed during their lifetime; however, MRI is still the best tool to monitor MS inflammatory activity. OBJECTIVE: This study aimed to evaluate the relevance of GBCA injections during the MRI follow-up of MS patients under natalizumab (Tysabri) treatment...

BACKGROUND: Though the Expanded Disability Status Scale (EDSS) is commonly used to assess disability level in relapsing-remitting multiple sclerosis (RRMS), the criteria defining disability progression are used for patients with a wide range of baseline levels of disability in relatively short-term trials. As a result, not all EDSS changes carry the same weight in terms of future disability, and treatment benefits such as decreased risk of reaching particular disability milestones may not be reliably captured...

BACKGROUND: Natalizumab (NAT), a humanized monoclonal antibody, binding in both α4β1 and α4β7 integrins, is approved for the treatment of Multiple Sclerosis (MS) and Crohn's Disease (CD). This review highlights the detailed Pharmacokinetics (PK) and Pharmacodynamics (PD) information of NAT, with the Pharmacogenomics (PG) properties of NAT. METHODS: We undertake a systemic English-language search of Medline, EMBASE, Cochrane Library electronic databases to identify all potential studies with PK, PD or PG properties of NAT (up to October 2017)...

Natalizumab (NTZ, Tysabri®; Biogen-Idec, Cambridge, MA, USA) is a humanized anti-α4 integrin monoclonal antibody, largely used in the treatment of Relapsing-Remitting Multiple Sclerosis (RRMS). Although the drug has shown great efficacy in clinical trials (AFFIRM and SENTINEL) and in post-marketing observational studies (TYGRIS), by reducing clinical signs as disability status progression, brain lesions and annual relapse rate, there are numerous papers concerning the associated risk of progressive multifocal leukoencephalopathy (PML)...

A 43-year-old female with multiple sclerosis developed urethral melanoma. The only potential risk factor was treatment with natalizumab, a humanized monoclonal antibody against α4 integrins. To investigate the risk-exposure relationship, we reviewed this case, all other published cases, and cases of natalizumab-associated melanoma reported to regulatory agencies. Data sources included the Food and Drug Administration's (FDA) Adverse Event Reporting System (FAERS) (2004-2014), a FDA Advisory Committee Meeting Report, and peer-reviewed publications...