Ponesimod in the Treatment of Relapsing Forms of Multiple Sclerosis: An Update on the Emerging Clinical Data

Immunomodulators and immunosuppressants for relapsing-remitting multiple sclerosis: a network meta-analysis

BACKGROUND

Different therapeutic strategies are available for the treatment of people with relapsing-remitting multiple sclerosis (RRMS), including immunomodulators, immunosuppressants and biological agents. Although each one of these therapies reduces relapse frequency and slows disability accumulation compared to no treatment, their relative benefit remains unclear. This is an update of a Cochrane review published in 2015.

OBJECTIVES

To compare the efficacy and safety, through network meta-analysis, of interferon beta-1b, interferon beta-1a, glatiramer acetate, natalizumab, mitoxantrone, fingolimod, teriflunomide, dimethyl fumarate, alemtuzumab, pegylated interferon beta-1a, daclizumab, laquinimod, azathioprine, immunoglobulins, cladribine, cyclophosphamide, diroximel fumarate, fludarabine, interferon beta 1-a and beta 1-b, leflunomide, methotrexate, minocycline, mycophenolate mofetil, ofatumumab, ozanimod, ponesimod, rituximab, siponimod and steroids for the treatment of people with RRMS.

SEARCH METHODS

CENTRAL, MEDLINE, Embase, and two trials registers were searched on 21 September 2021 together with reference checking, citation searching and contact with study authors to identify additional studies. A top-up search was conducted on 8 August 2022.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that studied one or more of the available immunomodulators and immunosuppressants as monotherapy in comparison to placebo or to another active agent, in adults with RRMS.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies and extracted data. We considered both direct and indirect evidence and performed data synthesis by pairwise and network meta-analysis. Certainty of the evidence was assessed by the GRADE approach.

MAIN RESULTS

We included 50 studies involving 36,541 participants (68.6% female and 31.4% male). Median treatment duration was 24 months, and 25 (50%) studies were placebo-controlled. Considering the risk of bias, the most frequent concern was related to the role of the sponsor in the authorship of the study report or in data management and analysis, for which we judged 68% of the studies were at high risk of other bias. The other frequent concerns were performance bias (34% judged as having high risk) and attrition bias (32% judged as having high risk). Placebo was used as the common comparator for network analysis. Relapses over 12 months: data were provided in 18 studies (9310 participants). Natalizumab results in a large reduction of people with relapses at 12 months (RR 0.52, 95% CI 0.43 to 0.63; high-certainty evidence). Fingolimod (RR 0.48, 95% CI 0.39 to 0.57; moderate-certainty evidence), daclizumab (RR 0.55, 95% CI 0.42 to 0.73; moderate-certainty evidence), and immunoglobulins (RR 0.60, 95% CI 0.47 to 0.79; moderate-certainty evidence) probably result in a large reduction of people with relapses at 12 months. Relapses over 24 months: data were reported in 28 studies (19,869 participants). Cladribine (RR 0.53, 95% CI 0.44 to 0.64; high-certainty evidence), alemtuzumab (RR 0.57, 95% CI 0.47 to 0.68; high-certainty evidence) and natalizumab (RR 0.56, 95% CI 0.48 to 0.65; high-certainty evidence) result in a large decrease of people with relapses at 24 months. Fingolimod (RR 0.54, 95% CI 0.48 to 0.60; moderate-certainty evidence), dimethyl fumarate (RR 0.62, 95% CI 0.55 to 0.70; moderate-certainty evidence), and ponesimod (RR 0.58, 95% CI 0.48 to 0.70; moderate-certainty evidence) probably result in a large decrease of people with relapses at 24 months. Glatiramer acetate (RR 0.84, 95%, CI 0.76 to 0.93; moderate-certainty evidence) and interferon beta-1a (Avonex, Rebif) (RR 0.84, 95% CI 0.78 to 0.91; moderate-certainty evidence) probably moderately decrease people with relapses at 24 months. Relapses over 36 months findings were available from five studies (3087 participants). None of the treatments assessed showed moderate- or high-certainty evidence compared to placebo. Disability worsening over 24 months was assessed in 31 studies (24,303 participants). Natalizumab probably results in a large reduction of disability worsening (RR 0.59, 95% CI 0.46 to 0.75; moderate-certainty evidence) at 24 months. Disability worsening over 36 months was assessed in three studies (2684 participants) but none of the studies used placebo as the comparator. Treatment discontinuation due to adverse events data were available from 43 studies (35,410 participants). Alemtuzumab probably results in a slight reduction of treatment discontinuation due to adverse events (OR 0.39, 95% CI 0.19 to 0.79; moderate-certainty evidence). Daclizumab (OR 2.55, 95% CI 1.40 to 4.63; moderate-certainty evidence), fingolimod (OR 1.84, 95% CI 1.31 to 2.57; moderate-certainty evidence), teriflunomide (OR 1.82, 95% CI 1.19 to 2.79; moderate-certainty evidence), interferon beta-1a (OR 1.48, 95% CI 0.99 to 2.20; moderate-certainty evidence), laquinimod (OR 1.49, 95 % CI 1.00 to 2.15; moderate-certainty evidence), natalizumab (OR 1.57, 95% CI 0.81 to 3.05), and glatiramer acetate (OR 1.48, 95% CI 1.01 to 2.14; moderate-certainty evidence) probably result in a slight increase in the number of people who discontinue treatment due to adverse events. Serious adverse events (SAEs) were reported in 35 studies (33,998 participants). There was probably a trivial reduction in SAEs amongst people with RRMS treated with interferon beta-1b as compared to placebo (OR 0.92, 95% CI 0.55 to 1.54; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

We are highly confident that, compared to placebo, two-year treatment with natalizumab, cladribine, or alemtuzumab decreases relapses more than with other DMTs. We are moderately confident that a two-year treatment with natalizumab may slow disability progression. Compared to those on placebo, people with RRMS treated with most of the assessed DMTs showed a higher frequency of treatment discontinuation due to AEs: we are moderately confident that this could happen with fingolimod, teriflunomide, interferon beta-1a, laquinimod, natalizumab and daclizumab, while our certainty with other DMTs is lower. We are also moderately certain that treatment with alemtuzumab is associated with fewer discontinuations due to adverse events than placebo, and moderately certain that interferon beta-1b probably results in a slight reduction in people who experience serious adverse events, but our certainty with regard to other DMTs is lower. Insufficient evidence is available to evaluate the efficacy and safety of DMTs in a longer term than two years, and this is a relevant issue for a chronic condition like MS that develops over decades. More than half of the included studies were sponsored by pharmaceutical companies and this may have influenced their results. Further studies should focus on direct comparison between active agents, with follow-up of at least three years, and assess other patient-relevant outcomes, such as quality of life and cognitive status, with particular focus on the impact of sex/gender on treatment effects.

Potential biomaterials and experimental animal models for inventing new drug delivery approaches in the neurodegenerative disorder: Multiple sclerosis

The tight junction of endothelial cells in the central nervous system (CNS) has an ideal characteristic, acting as a biological barrier that can securely regulate the movement of molecules in the brain. Tightly closed astrocyte cell junctions on blood capillaries are the blood-brain barrier (BBB). This biological barrier prohibits the entry of polar drugs, cells, and ions, which protect the brain from harmful toxins. However, delivering any therapeutic agent to the brain in neurodegenerative disorders (i.e., schizophrenia, multiple sclerosis, etc.) is extremely difficult. Active immune responses such as microglia, astrocytes, and lymphocytes cross the BBB and attack the nerve cells, which causes the demyelination of neurons. Therefore, there is a hindrance in transmitting electrical signals properly, resulting in blindness, paralysis, and neuropsychiatric problems. The main objective of this article is to shed light on the performance of biomaterials, which will help researchers to create nanocarriers that can cross the blood-brain barrier and achieve a therapeutic concentration of drugs in the CNS of patients with multiple sclerosis (MS). The present review focuses on the importance of biomaterials with diagnostic and therapeutic efficacy that can help enhance multiple sclerosis therapeutic potential. Currently, the development of MS in animal models is limited by immune responses, which prevent MS induction in healthy animals. Therefore, this article also showcases animal models currently used for treating MS. A future advance in developing a novel effective strategy for treating MS is now a potential area of research.

Ponesimod-Associated Macular Edema: Onset and Resolution

Purpose: To present a patient with cystoid macular edema (CME) associated with ponesimod use and offer suggestions for the management of this condition. Methods: A case report is presented. Results: A 75-year-old woman with relapsing-remitting multiple sclerosis had an unremarkable baseline ophthalmic examination prior to starting ponesimod. At her 9-month follow-up, an examination showed the development of CME in the left eye. The patient's macular edema fully resolved after transitioning off ponesimod to an alternative systemic medication and starting treatment with a topical corticosteroid and nonsteroidal anti-inflammatory drug. Conclusions: To our knowledge, this is the first case report discussing the entity and management of ponesimod-associated macular edema. Ponesimod cessation and concomitant topical therapy can result in successful resolution of macular edema.

The role of sphingosine-1-phosphate in the development and progression of Parkinson's disease

Parkinson's disease (PD) could be viewed as a proteinopathy caused by changes in lipids, whereby modifications in lipid metabolism may lead to protein alterations, such as the accumulation of alpha-synuclein (α-syn), ultimately resulting in neurodegeneration. Although the loss of dopaminergic neurons in the substantia nigra is the major clinical manifestation of PD, the etiology of it is largely unknown. Increasing evidence has highlighted the important role of lipids in the pathophysiology of PD. Sphingosine-1-phosphate (S1P), a signaling lipid, has been suggested to have a potential association with the advancement and worsening of PD. Therefore, better understanding the mechanisms and regulatory proteins is of high interest. Most interestingly, S1P appears to be an important target to offers a new strategy for the diagnosis and treatment of PD. In this review, we first introduce the basic situation of S1P structure, function and regulation, with a special focus on the several pathways. We then briefly describe the regulation of S1P signaling pathway on cells and make a special focused on the cell growth, proliferation and apoptosis, etc. Finally, we discuss the function of S1P as potential therapeutic target to improve the clinical symptoms of PD, and even prevent the progression of the PD. In the context of PD, the functions of S1P modulators have been extensively elucidated. In conclusion, S1P modulators represent a novel and promising therapeutic principle and therapeutic method for PD. However, more research is required before these drugs can be considered as a standard treatment option for PD.

Comparison of Pharmacological Therapies in Relapse Rates in Patients With Relapsing-Remitting Multiple Sclerosis

Multiple sclerosis (MS) is a chronic autoimmune neurological disorder that significantly impacts the central nervous system (CNS), which includes the brain and spinal cord. Approximately 2.8 million individuals are believed to be living with MS worldwide. The management of MS has evolved considerably over the years, offering a multitude of guidelines, diverse treatment options, and different approaches to signs and symptoms. The present systematic literature review serves as a comprehensive analysis of the current therapeutic options for MS. It provides a thorough literature review of Food and Drug Administration (FDA)-approved drugs comparing their various clinical end points while concurrently assessing their risk-benefit ratio. It also provides an extensive review of current guidelines and offers an in-depth examination of the different approaches to MS. Through this multifaceted approach, this paper facilitates easy access to available treatment options and aims to aid healthcare providers in decision-making as well as providing a foundation for future research aimed at enhancing treatment options for MS.

Discovery of a Promising Fluorine-18 Positron Emission Tomography Radiotracer for Imaging Sphingosine-1-Phosphate Receptor 1 in the Brain

Sphingosine-1-phosphate receptor 1 (S1PR1) is recognized as a novel therapeutic and diagnostic target in neurological disorders. We recently transferred the S1PR1 radioligand [11C]CS1P1 into clinical investigation for multiple sclerosis. Herein, we reported the design, synthesis and evaluation of novel F-18 S1PR1 radioligands. We combined the structural advantages of our two lead S1PR1 radioligands and synthesized 14 new S1PR1 compounds, then performed F-18 radiochemistry on the most promising compounds. Compound 6h is potent (IC50 = 8.7 nM) and selective for S1PR1. [18F]6h exhibited a high uptake in macaque brain (SUV > 3.0) and favorable brain washout pharmacokinetics in positron emission tomography (PET) study. PET blocking and displacement studies confirmed the specificity of [18F]6h in vivo. Radiometabolite analysis confirmed no radiometabolite of [18F]6h entered into the brain to confound the PET measurement. In summary, [18F]6h is a promising radioligand to image S1PR1 and worth translational clinical investigation for humans with brain disorders.

Ponesimod: An Oral Second-Generation Selective Sphingosine 1-Phosphate Receptor Modulator for the Treatment of Multiple Sclerosis

OBJECTIVE

To describe the safety, efficacy, and potential role in therapy of ponesimod, which was recently approved by the Food and Drug Administration (FDA) as a therapeutic option for the treatment of multiple sclerosis (MS).

DATA SOURCES

A PubMed literature search using the following terms: ponesimod and MS (January 1, 2012-October 31, 2022). FDA product labeling was also reviewed for pertinent data sources.

STUDY SELECTION AND DATA EXTRACTION

All relevant English-language articles examining efficacy and/or safety of ponesimod were considered for inclusion.

DATA SYNTHESIS

Ponesimod is an orally administered second-generation sphingosine 1-phospate (S1-P) receptor modulator classified as a disease modifying treatment (DMT) for MS. Clinical studies have shown that ponesimod prevents relapse in patients with relapsing-remitting MS (RRMS) and has superior efficacy compared with teriflunomide. Nasopharyngitis, upper respiratory tract infections, headache, high blood pressure, and liver dysfunction were some of the common adverse effects associated with ponesimod. Dyspnea, bradyarrhythmias, atrioventricular conduction delays, and macular edema were some of the rare but serious adverse effects associated with ponesimod.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE IN COMPARISON WITH EXISTING AGENTS

Some advantages of ponesimod over other S1-P receptor modulators approved for RRMS include selectivity for the S1-P₁ receptor and short half-life, which allows for quick reversal of immunosuppressive effects. However, data from long-term efficacy and safety studies and more direct comparison studies with other DMTs are required.

CONCLUSION

Currently available data suggest that ponesimod is a useful addition to other high-efficacy DMTs available to treat patients with MS.

Autoreactive lymphocytes in multiple sclerosis: Pathogenesis and treatment target

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) characterized by destruction of the myelin sheath structure. The loss of myelin leads to damage of a neuron’s axon and cell body, which is identified as brain lesions on magnetic resonance image (MRI). The pathogenesis of MS remains largely unknown. However, immune mechanisms, especially those linked to the aberrant lymphocyte activity, are mainly responsible for neuronal damage. Th1 and Th17 populations of lymphocytes were primarily associated with MS pathogenesis. These lymphocytes are essential for differentiation of encephalitogenic CD8⁺ T cell and Th17 lymphocyte crossing the blood brain barrier and targeting myelin sheath in the CNS. B-lymphocytes could also contribute to MS pathogenesis by producing anti-myelin basic protein antibodies. In later studies, aberrant function of Treg and Th9 cells was identified as contributing to MS. This review summarizes the aberrant function and count of lymphocyte, and the contributions of these cell to the mechanisms of MS. Additionally, we have outlined the novel MS therapeutics aimed to amend the aberrant function or counts of these lymphocytes.