Exploring the Latest Developments in Multiple Sclerosis: A 5-Year Overview

Multiple sclerosis (MS) is an autoimmune disease of the brain and central nervous system, affecting an estimated 2.8 million people worldwide,¹ and is one of the most common disabilities in young adults. MS is a complex disease and symptoms will vary among individuals, but typically include muscle weakness, impaired vision, mobility issues and speech difficulties. Both genetic and environmental factors contribute to the risk of developing MS. Family history elevates the risk of getting MS, with 2-3% chance of a child or sibling inheritance from someone with MS. Other risk factors include smoking, obesity, and vitamin D deficiency.

MS occurs when the body’s immune cells, such as T and B lymphocytes and macrophages, attack myelin, disrupting the flow of electrical signals between the brain and body. T regulatory cells do not work properly in MS, leading to inflammation and myelin degradation. While initial focus was primarily around T cell research, emerging evidence suggests B cells may also be significant in MS pathogenesis. B cells, which act as antigen-presenting cells, activate T cells, causing the immune system to attack the body’s own cells.² New studies have also revealed that inflammasomes (protein complexes involved in the activation of pro-inflammatory interleukins) may contribute to the etiology of MS by initiating immune response and inflammation – a hallmark of MS.³

Currently there is no cure for MS, so managing the disease involves utilizing a range of strategies. This includes disease-modifying therapies, symptomatic treatment, lifestyle changes, psychological support, and rehabilitation interventions to improve mental health and quality of life. According to Causaly, the first disease-modifying therapy, interferon beta-1b (Betaseron), was approved by the FDA in 1993 for MS treatment.

In the last 5 years, 293 treatments for MS have been evaluated in clinical trials, according to Causaly data. During this period, a total of 162 treatments have been investigated, excluding therapeutic and preventative procedures. Causaly refines these based on the Anatomical Therapeutic Chemical (ATC) classification system, enabling users to easily understand the properties and potential uses of drugs. For instance, since 2018, 22.2% of MS treatments under clinical trials can be categorized into the antineoplastic and immunomodulating agents (as depicted in Figure 1). Note, while ATC categories are used to classify drugs, they are not mutually exclusive and hence, drugs may fall into multiple categories.

Recent research suggests B cells have a crucial role in MS treatment, spurring investigations into inhibiting Bruton’s Tyrosine Kinase (BTK) – an enzyme that regulates the activation and development of B cells. Excitingly, there are numerous BTK inhibitors currently undergoing clinical trials, such as, tolebrutinib, fenebrutinib and evobrutinib. On another note, stem cell transplantation holds incredible potential for MS treatment. A phase I trial investigating the application of allogeneic stem cell transplantation as a therapeutic intervention for progressive MS has demonstrated encouraging results.⁴

As we celebrate World MS Day on 30th May 2023, it’s a great opportunity to reflect on the significant strides that have been made in MS research over the past 5 years. However, despite these advances, we still face significant challenges due to the heterogeneity of the disease and the existence of patients who do not respond to current treatment options. It is crucial to continue innovating and discovering new treatment options to address these challenges and improve the outcomes for MS sufferers worldwide.