Natalizumab treatment for multiple sclerosis: Middle East and North Africa regional recommendations for patient selection and monitoring

The Effects of Neuroactive Steroids on Myelin in Health and Disease

Myelin plays a pivotal role in the efficient transmission of nerve impulses. Disruptions in myelin integrity are associated with numerous neurological disorders, including multiple sclerosis. In the central nervous system (CNS), myelin is formed by oligodendrocytes. Remyelination refers to the re-formation of the damaged myelin sheath by newly formed oligodendrocytes. Steroids have gained attention for their potential modulatory effects on myelin in both health and disease. Steroids are traditionally associated with endocrine functions, but their local synthesis within the nervous system has generated significant interest. The term "neuroactive steroids" refers to steroids that can act on cells of the nervous system. In the healthy state, neuroactive steroids promote myelin formation, maintenance, and repair by enhancing oligodendrocyte differentiation and maturation. In pathological conditions, such as demyelination injury, multiple neuroactive steroids have shown promise in promoting remyelination. Understanding the effects of neuroactive steroids on myelin could lead to novel therapeutic approaches for demyelinating diseases and neurodegenerative disorders. This review highlights the potential therapeutic significance of neuroactive steroids in myelin-related health and diseases. We review the synthesis of steroids by neurons and glial cells and discuss the roles of neuroactive steroids on myelin structure and function in health and disease. We emphasize the potential promyelinating effects of the varying levels of neuroactive steroids during different female physiological states such as the menstrual cycle, pregnancy, lactation, and postmenopause.

Silent lesions on MRI imaging - Shifting goal posts for treatment decisions in multiple sclerosis

BACKGROUND

The current best practice suggests yearly magnetic resonance imaging (MRI) to monitor treatment response in multiple sclerosis (MS) patients.

OBJECTIVE

To evaluate the current practice of clinicians changing MS treatment based on subclinical new MRI lesions alone.

METHODS

Using MSBase, an international MS patient registry with MRI data, we analysed the probability of treatment change among patients with clinically silent new MRI lesions.

RESULTS

A total of 8311 MRI brain scans of 4232 patients were identified. Around 26.9% (336/1247) MRIs with one new T2 lesion were followed by disease-modifying therapy (DMT) change, increasing to 50.2% (129/257) with six new T2 lesions. DMT change was twice as likely with new T1 contrast enhancing compared to new T2 lesions odds ratio (OR): 2.43, 95% confidence interval (CI): 2.00-2.96 vs OR: 1.26 (95% CI: 1.22-1.29). DMT change with new MRI lesions occurred most frequently with 'injectable' DMTs. The probability of switching therapy was greater only after high-efficacy therapies became available in 2007 (after, OR: 1.43, 95% CI: 1.28-1.59 vs before, OR: 0.98, 95% CI: 0.520-1.88).

CONCLUSION

MS clinicians rely increasingly on MRI alone in their treatment decisions, utilizing low thresholds (1 new T2 lesion) for optimizing MS therapy. This signals a shift towards no evidence of disease activity (NEDA)-3 since high-efficacy therapies became available.

Natalizumab Treatment for Relapsing-Remitting Multiple Sclerosis: The Experience From Saudi Arabia

BACKGROUND

Natalizumab is the first targeted humanized monoclonal antibody to be approved for the treatment of relapsing-remitting multiple sclerosis (RRMS). Natalizumab appears to be more effective than current first-line disease-modifying therapies. In our study, we aimed to evaluate the outcome of Saudi patients with active RRMS treated with natalizumab and compare the results with other outcomes in the Gulf and international trials.

METHODS

We conducted a retrospective single-center observational study involving 32 patients with RRMS at King Abdulaziz Medical City in Jeddah, Saudi Arabia. The inclusion criteria included all patients diagnosed with RRMS according to the revised McDonald criteria who are currently receiving or received natalizumab treatment in the past for a minimum of 6 months.

RESULTS

The mean baseline Expanded Disability Status Scale score was 4.50 ± 1.80 (range, 1.5-6; median, 5), whereas the mean Expanded Disability Status Scale at the follow-up was 4.02 ± 2.08 (range, 1-6; median, 4.25) (P = 0.3274). The mean annualized relapse rate was significantly reduced from 2.41 ± 2.48 at baseline to 0.16 ± 0.37 at the last follow-up (P < 0.0001). Twenty-seven patients (84.4%) had no relapses since the treatment with natalizumab was started, whereas 5 patients (15.6%) had only 1 relapse. In addition to clinically measurable improvement, radiological improvement was observed through magnetic resonance imaging. Magnetic resonance imaging activity was significantly improved at follow-up magnetic resonance imaging studies when compared with baseline.

CONCLUSIONS

Our single-center study in Saudi Arabia provides further support for the efficacy of natalizumab in the clinical practice setting. The sharp decrease in relapse rate and progression of disability following the initiation of natalizumab treatment was similar to other observational studies conducted in different countries across the globe. Natalizumab was a satisfactory therapy for the management of our MS population, both from the patients' and the physicians' perspectives.

Progressive Multifocal Leukoencephalopathy and Monoclonal Antibodies: A Review

Progressive multifocal leukoencephalopathy (PML) is a viral infection predominantly seen in patients with HIV infection. However, with the increased use of monoclonal antibodies (MAB) for various lymphoproliferative disorders, we are now seeing this infection in non-HIV patients on drugs such as natalizumab, rituximab, and so on. The aim of this article is to review the relationship between the occurrence of PML and MAB used in the treatment of hematological malignancies and autoimmune diseases. Review of articles from PubMed-indexed journals which study PML in relation to the use of MAB. Relevant literature demonstrated an increased risk of reactivation of latent John Cunningham polyomavirus (JCV) resulting in development of PML in patients on long-term therapy with MAB. The highest incidence of 1 PML case per 1000 treated patients and 1 case per 32 000 was observed in patients treated with natalizumab and rituximab, respectively. Serological and polymerase chain reaction tests for the detection of JCV can be helpful in risk stratification of patients for the development of PML before and during therapy with MAB. Treatment with MAB can result in development of PML. Clinicians should include PML in differential diagnosis in patients treated with these agents if they manifest central nervous system symptoms.