Pharmacokinetics and pharmacodynamics of ponesimod, a selective S1P1 receptor modulator, in the first-in-human study

Dopamine β-hydroxylase shapes intestinal inflammation through modulating T cell activation

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic and relapsing disease characterized by immune-mediated dysfunction of intestinal homeostasis. Alteration of the enteric nervous system and the subsequent neuro-immune interaction are thought to contribute to the initiation and progression of IBD. However, the role of dopamine beta-hydroxylase (DBH), an enzyme converting dopamine into norepinephrine, in modulating intestinal inflammation is not well defined.

METHODS

CD4+CD45RBhighT cell adoptive transfer, and 2,4-dinitrobenzene sulfonic acid (DNBS) or dextran sodium sulfate (DSS)-induced colitis were collectively conducted to uncover the effects of DBH inhibition by nepicastat, a DBH inhibitor, in mucosal ulceration, disease severity, and T cell function.

RESULTS

Inhibition of DBH by nepicastat triggered therapeutic effects on T cell adoptive transfer induced chronic mouse colitis model, which was consistent with the gene expression of DBH in multiple cell populations including T cells. Furthermore, DBH inhibition dramatically ameliorated the disease activity and colon shortening in chemically induced acute and chronic IBD models, as evidenced by morphological and histological examinations. The reshaped systemic inflammatory status was largely associated with decreased pro-inflammatory mediators, such as TNF-α, IL-6 and IFN-γ in plasma and re-balanced Th1, Th17 and Tregs in mesenteric lymph nodes (MLNs) upon colitis progression. Additionally, the conversion from dopamine (DA) to norepinephrine (NE) was inhibited resulting in increase in DA level and decrease in NE level and DA/NE showed immune-modulatory effects on the activation of immune cells.

CONCLUSION

Modulation of neurotransmitter levels via inhibition of DBH exerted protective effects on progression of murine colitis by modulating the neuro-immune axis. These findings suggested a promising new therapeutic strategy for attenuating intestinal inflammation.

Icanbelimod (CBP-307), a next-generation Sphingosine-1-phosphate receptor modulator, in healthy men: pharmacokinetics, pharmacodynamics, safety, and tolerability in a randomized trial in Australia

Background

Icanbelimod (formerly CBP-307) is a next-generation S1PR modulator, targeting S1PR1. In this first-in-human study, icanbelimod was investigated in healthy men in Australia.

Methods

Participants were randomized 3:1, double-blind, to icanbelimod or placebo in four single-dose cohorts (0.1 mg, 0.25 mg, 0.5 mg [n=8 per cohort], 2.5 mg [n=4]) or for 28-days once-daily treatment in two cohorts (0.15 mg, 0.25 mg [n=8 per cohort]). Participants in the 0.25-mg cohort received 0.1 mg on Day 1. Treatments were administered orally after fasting; following one-week washout, icanbelimod was administered after breakfast in the 0.5-mg cohort.

Results

Icanbelimod exposure increased rapidly and dose-dependently with single and multiple dosing (Tmax 4-7 hours). Lymphocyte counts decreased rapidly after single (-11%, 0.1 mg; -40%, 0.25 mg; -71%, 0.5 mg; -77%, 2.5 mg) and multiple doses (-49%, 0.15 mg; -75%, 0.25 mg), and recovered quickly, 7 days after dosing. After single-dose 0.5 mg, although a high-fat breakfast versus fasting did not affect maximal decrease, lymphocyte counts tended to be lower after breakfast across most timepoints up to 72 hours. Twenty-eight participants (63.6%) experienced mainly mild treatment-emergent adverse events (TEAEs). After single-dose icanbelimod, the most common TEAEs were headache (28.6%, n=6) and dizziness (19.0%, n=4). Three participants experienced transient bradycardia, with one serious, following single-dose 2.5 mg icanbelimod. After multiple-dose icanbelimod, the most common TEAEs were headache (50.0%, n=6) and lymphopenia (41.7%, n=5), and two participants withdrew due to non-serious TEAEs. Up-titration attenuated heart rate reductions.

Conclusion

Icanbelimod was well-tolerated up to 0.5 mg and effectively reduced lymphocyte counts.

Clinical trial registration

ClinicalTrials.gov, identifier NCT02280434.b.

Safety, Pharmacokinetics, and Pharmacodynamics of Etrasimod: Single and Multiple Ascending Dose Studies in Healthy Adults

Etrasimod is an investigational, once-daily, oral, selective sphingosine 1-phosphate receptor 1,4,5 modulator in development for immune-mediated inflammatory diseases (IMIDs). Here, we report the human safety, pharmacokinetics, and pharmacodynamics of etrasimod obtained from both a single ascending dose (SAD; 0.1-5 mg) study and a multiple ascending dose (MAD; 0.35-3 mg once daily) study. Overall, 99 healthy volunteers (SAD n = 40, MAD n = 59) completed the 2 studies. Evaluated single and multiple doses were well tolerated up to 3 mg without severe adverse events (AEs). Gastrointestinal disorders were the most common etrasimod-related AEs. Over the evaluated single- and multiple-dose ranges, dose-proportional and marginally greater-than-dose-proportional etrasimod plasma exposure were observed, respectively. At steady state, etrasimod oral clearance and half-life mean values ranged from 1.0 to 1.2 L/h and 29.7 to 36.4 hours, respectively. Dose-dependent total peripheral lymphocyte reductions occurred following etrasimod single and multiple dosing. Etrasimod multiple dosing resulted in reductions from baseline in total lymphocyte counts ranging from 41.1% to 68.8% after 21 days. Lymphocyte counts returned to normal range within 7 days following treatment discontinuation. Heart rate lowering from pretreatment baseline on etrasimod dosing was typically mild, with mean reductions seen after the first dose of up to 19.5 bpm (5 mg dose). The favorable safety, pharmacokinetic, and pharmacodynamic properties of etrasimod in humans supported its further development and warranted its investigation for treatment of IMIDs.

Efficacy and Safety of Ponesimod Compared with Teriflunomide in Female Patients with Relapsing Multiple Sclerosis: Findings from the Pivotal OPTIMUM Study

Background: Multiple sclerosis (MS) is threefold more prevalent in women than men. However, sex-specific efficacy analysis for MS disease-modifying therapies is not typically performed. Methods: Post hoc analyses of data from female patients enrolled in the phase 3, double-blind OPTIMUM study of relapsing MS were carried out. Eligible adults were randomized to ponesimod 20 mg or teriflunomide 14 mg once daily for up to 108 weeks. The primary endpoint was annualized relapse rate (ARR); secondary endpoints included change in symptom domain of Fatigue Symptom and Impact Questionnaire-Relapsing Multiple Sclerosis (FSIQ-RMS) at week 108, number of combined unique active lesions (CUALs) per year on magnetic resonance imaging, and time to 12- and 24-week confirmed disability accumulation (CDA). Results: A total of 735 female patients (581 of childbearing potential) were randomized to ponesimod (n = 363, 49.4%) or teriflunomide (n = 372, 50.6%). Relative risk reduction in the ARR for ponesimod versus teriflunomide was 33.1% (mean, 0.192 vs. 0.286, respectively; p < 0.002). Mean difference in FSIQ-RMS for ponesimod versus teriflunomide was -4.34 (0.12 vs. 4.46; p = 0.002); rate ratio in CUALs per year, 0.601 (1.45 vs. 2.41; p < 0.0001), and hazard ratio for time to 12- and 24-week CDA risk estimates, 0.83 (10.7% vs. 12.9%; p = 0.38) and 0.91 (8.8% vs. 9.7%; p = 0.69), respectively. Incidence of treatment-emergent adverse events was similar between treatment groups (89.0% and 90.1%). Conclusions: Analyses demonstrate the efficacy and safety of ponesimod, versus active comparator, for women with relapsing MS, supporting data-informed decision-making for women with MS. Clinical Trial Registration Number: NCT02425644.

Cardiovascular Evaluation of Etrasimod, a Selective Sphingosine 1-phosphate Receptor Modulator, in Healthy Adults: Results of a Randomized, Thorough QT/QTc Study

Etrasimod is an investigational, once-daily, oral, selective sphingosine 1-phosphate receptor 1,4,5 modulator used as an oral treatment option for immune-mediated inflammatory disorders. This randomized, double-blind, placebo- and positive-controlled, parallel-group, healthy adult study investigated etrasimod's effect on the QT interval and other electrocardiogram parameters. All participants received etrasimod-matched placebo on day 1. Group A received once-daily, multiple ascending doses of etrasimod (2-4 mg) on days 1-14 and moxifloxacin-matched placebo on days 1 and 15. Group B received etrasimod-matched placebo on days 1-14 and either moxifloxacin 400 mg or moxifloxacin-matched placebo on days 1 and 15. The primary analysis was a concentration-QTc analysis using a corrected QT interval by Fridericia (QTcF). The etrasimod concentration-QTc analysis predicted placebo-corrected change from baseline QTcF (ΔΔQTcF) values and associated 90% confidence intervals remained <10 milliseconds over the observed etrasimod plasma concentration range (≤279 ng/mL). Etrasimod was associated with mild, transient, asymptomatic heart rate slowing that was most pronounced on day 1 (2 mg, first dose). The largest-by-time point mean placebo-corrected changes in heart rate from time-matched day -1 baseline (∆∆HR) on days 1, 7 (2 mg, last dose), and 14 (4 mg, last dose) were -15.1, -8.5, and -6.0 bpm, respectively. Etrasimod's effects on PR interval were small, with the largest least squares mean placebo-corrected change from baseline in PR interval (∆∆PR) being 6.6 milliseconds. No episodes of atrioventricular block were observed. Thus, multiple ascending doses of etrasimod were not associated with clinically relevant QT/QTc effects in healthy adults and only had a mild, transient, and asymptomatic impact on heart rate.

The sphingosine-1-phosphate receptor 1 modulator ponesimod repairs cuprizone-induced demyelination and induces oligodendrocyte differentiation

Sphingosine-1-phosphate receptor (S1PR) modulators are clinically used to treat relapse-remitting multiple sclerosis (MS) and the early phase of progressive MS when inflammation still prevails. In the periphery, S1PR modulators prevent lymphocyte egress from lymph nodes, hence hampering neuroinflammation. Recent findings suggest a role for S1PR modulation in remyelination. As the Giα-coupled S1P1 subtype is the most prominently expressed S1PR in oligodendrocyte precursor cells (OPCs), selective modulation (functional antagonism) of S1P1 may have direct effects on OPC functionality. We hypothesized that functional antagonism of S1P1 by ponesimod induces remyelination by boosting OPC differentiation. In the cuprizone mouse model of demyelination, we found ponesimod to decrease the latency time of visual evoked potentials compared to vehicle conditions, which is indicative of functional remyelination. In addition, the Y maze spontaneous alternations test revealed that ponesimod reversed cuprizone-induced working memory deficits. Myelin basic protein (MBP) immunohistochemistry and transmission electron microscopy of the corpus callosum revealed an increase in myelination upon ponesimod treatment. Moreover, treatment with ponesimod alone or in combination with A971432, an S1P5 monoselective modulator, significantly increased primary mouse OPC differentiation based on O4 immunocytochemistry. In conclusion, S1P1 functional antagonism by ponesimod increases remyelination in the cuprizone model of demyelination and significantly increases OPC differentiation in vitro.

Clinical Pharmacokinetics of Ponesimod, a Selective S1P1 Receptor Modulator, in the Treatment of Multiple Sclerosis

Ponesimod, a selective, rapidly reversible, and orally active, sphingosine-1 phosphate receptor (S1P) modulator, is indicated for the treatment of relapsing-remitting multiple sclerosis (RRMS). The clinical pharmacokinetics (PK) and pharmacodynamics (PD) of ponesimod was studied in 16 phase I, one phase II, and one phase III clinical studies. Ponesimod population PK was characterized by an open two-compartment disposition model with a terminal half-life of 33 h (accumulation factor of 2- to 2.6-fold), and fast and almost complete oral absorption (absolute oral bioavailability: 84%), reaching peak plasma and blood concentrations within 2-4 h. Ponesimod is highly metabolized, and the parent compound along with its two major (non-clinically active) metabolites are mainly excreted in the feces (recovery: 57.3-79.6%) and to a lesser extent in the urine (recovery: 10.3-18.4%). Additionally, the population PKPD model characterized the ponesimod effects on heart rate: a transient, dose-dependent decrease in heart rate in the first days of dosing, that is mitigated by administering the first doses of ponesimod treatment using a gradual up-titration schedule, before reaching the daily maintenance dose of 20 mg. This selected maintenance dose has been shown to be superior in reducing annualized relapse rate (ARR) when compared with teriflunomide in a pivotal phase III study. Furthermore, a dose-dependent reduction of peripheral lymphocyte counts that is sustained with continued daily oral dosing of ponesimod and is rapidly (4-7 days) reversible upon drug discontinuation has been characterized with an indirect response model.

Exploration of Tetrahydroisoquinoline- and Benzo[c]azepine-Based Sphingosine 1-Phosphate Receptor 1 Agonists for the Treatment of Multiple Sclerosis

Because of the wide use of Fingolimod for the treatment of multiple sclerosis (MS) and its cardiovascular side effects such as bradycardia, second-generation sphingosine 1-phosphate receptor 1 (S1P1) agonist drugs for MS have been developed and approved by FDA. The issue of bradycardia is still present with the new drugs, however, which necessitates further exploration of S1P1 agonists with improved safety profiles for next-generation MS drugs. Herein, we report a tetrahydroisoquinoline or a benzo[c]azepine core-based S1P1 agonists such as 32 and 60 after systematic examination of hydrophilic groups and cores. We investigated the binding modes of our representative compounds and their molecular interactions with S1P1 employing recent S1P1 cryo-EM structures. Also, favorable ADME properties of our compounds were shown. Furthermore, in vivo efficacy of our compounds was clearly demonstrated with PLC and EAE studies. Also, the preliminary in vitro cardiovascular safety of our compound was verified with human iPSC-derived cardiomyocytes.

The S1P receptor 1 antagonist Ponesimod reduces TLR4-induced neuroinflammation and increases Aβ clearance in 5XFAD mice

BACKGROUND

Previously, we showed that the sphingosine-1-phosphate (S1P) transporter spinster 2 (Spns2) mediates activation of microglia in response to amyloid β peptide (Aβ). Here, we investigated if Ponesimod, a functional S1P receptor 1 (S1PR1) antagonist, prevents Aβ-induced activation of glial cells and Alzheimer's disease (AD) pathology.

METHODS

We used primary cultures of glial cells and the 5XFAD mouse model to determine the effect of Aβ and Ponesimod on glial activation, Aβ phagocytosis, cytokine levels and pro-inflammatory signaling pathways, AD pathology, and cognitive performance.

FINDINGS

Aβ42 increased the levels of TLR4 and S1PR1, leading to their complex formation. Ponesimod prevented the increase in TLR4 and S1PR1 levels, as well as the formation of their complex. It also reduced the activation of the pro-inflammatory Stat1 and p38 MAPK signaling pathways, while activating the anti-inflammatory Stat6 pathway. This was consistent with increased phagocytosis of Aβ42 in primary cultured microglia. In 5XFAD mice, Ponesimod decreased the levels of TNF-α and CXCL10, which activate TLR4 and Stat1. It also increased the level of IL-33, an anti-inflammatory cytokine that promotes Aβ42 phagocytosis by microglia. As a result of these changes, Ponesimod decreased the number of Iba-1+ microglia and GFAP+ astrocytes, and the size and number of amyloid plaques, while improving spatial memory as measured in a Y-maze test.

INTERPRETATION

Ponesimod targeting S1PR1 is a promising therapeutic approach to reprogram microglia, reduce neuroinflammation, and increase Aβ clearance in AD.

FUNDING

NIHR01AG064234, RF1AG078338, R21AG078601, VAI01BX003643.

Molecular and neuroimmune pharmacology of S1P receptor modulators and other disease-modifying therapies for multiple sclerosis

Multiple sclerosis (MS) is a neurological, immune-mediated demyelinating disease that affects people in the prime of life. Environmental, infectious, and genetic factors have been implicated in its etiology, although a definitive cause has yet to be determined. Nevertheless, multiple disease-modifying therapies (DMTs: including interferons, glatiramer acetate, fumarates, cladribine, teriflunomide, fingolimod, siponimod, ozanimod, ponesimod, and monoclonal antibodies targeting ITGA4, CD20, and CD52) have been developed and approved for the treatment of MS. All the DMTs approved to date target immunomodulation as their mechanism of action (MOA); however, the direct effects of some DMTs on the central nervous system (CNS), particularly sphingosine 1-phosphate (S1P) receptor (S1PR) modulators, implicate a parallel MOA that may also reduce neurodegenerative sequelae. This review summarizes the currently approved DMTs for the treatment of MS and provides details and recent advances in the molecular pharmacology, immunopharmacology, and neuropharmacology of S1PR modulators, with a special focus on the CNS-oriented, astrocyte-centric MOA of fingolimod.

Pharmacokinetic-Pharmacodynamic Modeling of the Ponesimod Effect on Heart Rate in Patients With Multiple Sclerosis

The purpose of this study was to characterize the ponesimod effect on the heart rate (HR) in patients with multiple sclerosis (MS). A previous pharmacokinetic (PK) and pharmacodynamic model developed in healthy participants was updated using data from phase II and III trials conducted in patients with MS. Clinically relevant covariates were assessed. Simulations were conducted to evaluate the impact of the lack of adherence to ponesimod treatment and provide guidance in cases of treatment re-initiation. The maximal effect parameter of the PK/HR model was lower in patients with MS (23.5% decrease) compared with healthy volunteers (43.2%). The effect of patient covariates on PK/HR was similar to those identified in healthy participants and not clinically relevant in patients with MS. The population PK/HR model well characterized the effect of ponesimod on the time course of HR in patients with MS. After 2 weeks of treatment with 10 mg or higher doses, the model indicated full tolerance development. After repeated dosing at 20 mg, tolerance was maintained > 60% of the steady-state tolerance for up to 4 days after the last dose. Re-initiating with gradual uptitration is recommended if drug discontinuation lasts ≥ 4 days. This managed the negative chronotropic effects of ponesimod. No bradycardia events were observed within the first 2 weeks of treatment in patients with relapsing MS with a baseline HR > 55 bpm. This justifies the recommendation included in the human prescription drug labeling to monitor HR after the first ponesimod dose in these patients.

The impact of sphingosine-1-phosphate receptor modulators on COVID-19 and SARS-CoV-2 vaccination

BACKGROUND

Sphingosine-one phosphate receptor (S1PR) modulation inhibits S1PR1-mediated lymphocyte migration, lesion formation and positively-impacts on active multiple sclerosis (MS). These S1PR modulatory drugs have different: European Union use restrictions, pharmacokinetics, metabolic profiles and S1PR receptor affinities that may impact MS-management. Importantly, these confer useful properties in dealing with COVID-19, anti-viral drug responses and generating SARS-CoV-2 vaccine responses.

OBJECTIVE

To examine the biology and emerging data that potentially underpins immunity to the SARS-CoV-2 virus following natural infection and vaccination and determine how this impinges on the use of current sphingosine-one-phosphate modulators used in the treatment of MS.

METHODS

A literature review was performed, and data on infection, vaccination responses; S1PR distribution and functional activity was extracted from regulatory and academic information within the public domain.

OBSERVATIONS

Most COVID-19 related information relates to the use of fingolimod. This indicates that continuous S1PR1, S1PR3, S1PR4 and S1PR5 modulation is not associated with a worse prognosis following SARS-CoV-2 infection. Whilst fingolimod use is associated with blunted seroconversion and reduced peripheral T-cell vaccine responses, it appears that people on siponimod, ozanimod and ponesimod exhibit stronger vaccine-responses, which could be related notably to a limited impact on S1PR4 activity. Whilst it is thought that S1PR3 controls B cell function in addition to actions by S1PR1 and S1PR2, this may be species-related effect in rodents that is not yet substantiated in humans, as seen with bradycardia issues. Blunted antibody responses can be related to actions on B and T-cell subsets, germinal centre function and innate-immune biology. Although S1P1R-related functions are seeming central to control of MS and the generation of a fully functional vaccination response; the relative lack of influence on S1PR4-mediated actions on dendritic cells may increase the rate of vaccine-induced seroconversion with the newer generation of S1PR modulators and improve the risk-benefit balance IMPLICATIONS: Although fingolimod is a useful asset in controlling MS, recently-approved S1PR modulators may have beneficial biology related to pharmacokinetics, metabolism and more-restricted targeting that make it easier to generate infection-control and effective anti-viral responses to SARS-COV-2 and other pathogens. Further studies are warranted.

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.

Current status and new developments in sphingosine-1-phosphate receptor antagonism: fingolimod and more

INTRODUCTION

Fingolimod was the first oral disease-modifying treatment approved for relapsing-remitting multiple sclerosis (MS) that serves as a sphingosine-1-phosphate receptor (S1PR) agonist. The efficacy is primarily mediated by S1PR subtype 1 activation, leading to agonist-induced down-modulation of receptor expression and further functional antagonism, blocking the egression of auto-aggressive lymphocytes from the lymph nodes in the peripheral compartment. The role of S1P signaling in the regulation of other pathways in human organisms through different S1PR subtypes has received much attention due to its immune-modulatory function and its significance for the regeneration of the central nervous system (CNS). The more selective second-generation S1PR modulators have improved safety and tolerability profiles.

AREAS COVERED

This review has been carried out based on current data on S1PR modulators, emphasizing the benefits of recent advances in this emergent class of immunomodulatory treatment for MS.

EXPERT OPINION

Ongoing clinical research suggests that S1PR modulators represent an alternative to first-line therapies in selected cases of MS. A better understanding of the relevance of selective S1PR pathways and the ambition to optimize selective modulation has improved the safety and tolerability of S1PR modulators in MS therapy and opened new perspectives for the treatment of other diseases.

Management of inflammatory bowel disease beyond tumor necrosis factor inhibitors: novel biologics and small-molecule drugs

The incidence and prevalence of inflammatory bowel disease (IBD), comprising Crohn's disease and ulcerative colitis, have increased in Asia and developing countries. In the past two decades, anti-tumor necrosis factor (TNF) agents have revolutionized the treatment of IBD, in part by decreasing the rates of complications and surgery. Although anti-TNF agents have changed the course of IBD, there are unmet needs in terms of primary and secondary non-responses and side effects such as infections and malignancies. Novel biologics and small-molecule drugs have been developed for IBD, and the medical treatment options have improved. These drugs include sphingosine-1-phosphate receptor modulators and anti-integrins to block immune cell migration, and cytokine and Janus kinase inhibitors to block immune cell communications. In this review, we discuss the approved novel biologics and small-molecule drugs, including several of those in the late stages of development, for the treatment of IBD.

Association between plasma apolipoprotein M and cardiac autonomic neuropathy in type 1 diabetes

AIM

Diabetes may lead to severe complications e.g. cardiac autonomic neuropathy (CAN) characterized by an increased risk of cardiovascular mortality. CAN is diagnosed by a decreased heart rate viability (HRV). Sphingosine-1-Phosphate (S1P) carried by the HDL-associated apolipoprotein M (apoM) is linked to a reduction in the heart rate, and treatment with an S1P-agonist increases HRV. The present study aimed to investigate if plasma apoM was associated with an increased risk of CAN.

METHODS

The study includes 278 individuals with Type 1 Diabetes recruited from Steno Diabetes Center in Copenhagen from 2010 to 2012.

RESULTS

A change of 0.1 µM plasma apoM was associated with the diagnosis of CAN (Odds ratio: 1.11 (1.02; 1.21), p = 0.013). ApoM plasma levels were also positively associated with CAN when adjusted for age and gender (Odds ratio: 1.11 (1.02; 1.21), p = 0.013) as well as lipids, beta-blockers, blood pressure, and alcohol (Odds ratio: 1.14 (1.04; 1.26), p = 0.005) and Hbga1c and time with diabetes (Odds ratio: 1.13 (1.02; 1.25), p = 0.01). Plasma apoM was also associated with a significantly lower SDNN as well as high frequency power in all adjusted models.

CONCLUSION

Increased plasma apoM was associated with an increased risk of CAN as well as a significant reduction in HRV indices. This could represent changes in parasympathetic activity, but, further studies are needed to also explore additional molecular alterations behind such observations.

Sphingosine-1-Phosphate (S1P) and S1P Signaling Pathway Modulators, from Current Insights to Future Perspectives

Sphingosine-1-phosphate (S1P) and S1P receptors (S1PR) are bioactive lipid molecules that are ubiquitously expressed in the human body and play an important role in the immune system. S1P-S1PR signaling has been well characterized in immune trafficking and activation in both innate and adaptive immune systems. Despite this knowledge, the full scope in the pathogenesis of autoimmune disorders is not well characterized yet. From the discovery of fingolimod, the first S1P modulator, until siponimod, the new molecule recently approved for the treatment of secondary progressive multiple sclerosis (SPMS), there has been a great advance in understanding the S1P functions and their involvement in immune diseases, including multiple sclerosis (MS). Modulation on S1P is an interesting target for the treatment of various autoimmune disorders. Improved understanding of the mechanism of action of fingolimod has allowed the development of the more selective second-generation S1PR modulators. Subtype 1 of the S1PR (S1PR1) is expressed on the cell surface of lymphocytes, which are known to play a major role in MS pathogenesis. The understanding of S1PR1’s role facilitated the development of pharmacological strategies directed to this target, and theoretically reduced the safety concerns derived from the use of fingolimod. A great advance in the MS treatment was achieved in March 2019 when the Food and Drug Association (FDA) approved Siponimod, for both active secondary progressive MS and relapsing–remitting MS. Siponimod became the first oral disease modifying therapy (DMT) specifically approved for active forms of secondary progressive MS. Additionally, for the treatment of relapsing forms of MS, ozanimod was approved by FDA in March 2020. Currently, there are ongoing trials focused on other new-generation S1PR1 modulators. This review approaches the fundamental aspects of the sphingosine phosphate modulators and their main similarities and differences.

Sphingosine 1-phosphate modulation and immune cell trafficking in inflammatory bowel disease

Immune cell trafficking is a critical element of the intestinal immune response, both in homeostasis and in pathological conditions associated with inflammatory bowel disease (IBD). This process involves adhesion molecules, chemoattractants and receptors expressed on immune cell surfaces, blood vessels and stromal intestinal tissue as well as signalling pathways, including those modulated by sphingosine 1-phosphate (S1P). The complex biological processes of leukocyte recruitment, activation, adhesion and migration have been targeted by various monoclonal antibodies (vedolizumab, etrolizumab, ontamalimab). Promising preclinical and clinical data with several oral S1P modulators suggest that inhibition of lymphocyte egress from the lymph nodes to the bloodstream might be a safe and efficacious alternative mechanism for reducing inflammation in immune-mediated disorders, including Crohn's disease and ulcerative colitis. Although various questions remain, including the potential positioning of S1P modulators in treatment algorithms and their long-term safety, this novel class of compounds holds great promise. This Review summarizes the critical mediators and mechanisms involved in immune cell trafficking in IBD and the available evidence for efficacy, safety and pharmacokinetics of S1P receptor modulators in IBD and other immune-mediated disorders. Further, it discusses potential future approaches to incorporate S1P modulators into the treatment of IBD.

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

Sphingosine 1-phosphate (S1P) receptors are bioactive lipid metabolites that bind five different types of receptors expressed ubiquitously in human body and mediate a broad range of biological functions. Targeting S1P receptors is nowadays a well-established pharmacological strategy to treat multiple sclerosis (MS). However, the adverse events associated with the ancestor (fingolimod), especially in terms of heart conduction and slow reversibility of its pharmacodynamics effect on lymphocytes, have stimulated a search for a S1P modulator with greater selectivity for S1P1 (the most important immune mechanism to prevent MS-related neuroinflammation). Ponesimod is a second-generation, orally active, directly bioavailable, highly selective, and rapidly reversible modulator of the S1P1 receptor. Gradual 14-day up-titration of ponesimod mitigates its first-dose effects on heart rate and facilitates its use over fingolimod, as it does not require first-dose cardiac monitoring. Ponesimod is rapidly eliminated within 1 week of discontinuation, thereby representing a more manageable approach in case of vaccination, pregnancy, or adverse events. However, the fast reversibility of ponesimod may also raise concerns about the possibility of a rapid reactivation of disease activity following its discontinuation. Ponesimod was recently approved for the treatment of relapsing MS forms on the basis of a Phase III, double-blind, double-dummy, randomized clinical trial (OPTIMUM) that demonstrated the superiority of ponesimod over teriflunomide on disease activity markers, without unexpected safety concerns. This review summarizes the pharmacodynamic and pharmacokinetic characteristics of ponesimod, and the main Phase II and III studies that led to its approval. Comparisons of ponesimod with other S1P receptor modulators currently available for MS (fingolimod, ozanimod, siponimod) are also provided.

Single‐dose of LC51‐0255, a Selective S1P 1 Receptor Modulator, Showed Dose‐dependent and Reversible Reduction of Absolute Lymphocyte Count in Humans

Reducing the peripheral absolute lymphocyte count (ALC) is a promising therapeutic approach in treating autoimmune diseases. LC51‐0255 is a sphingosine‐1‐phosphate 1 receptor modulator, which is known to decrease the peripheral ALC. We aimed to assess the pharmacokinetics (PKs), pharmacodynamics (PDs), safety, and tolerability profiles of LC51‐0255 after a single oral administration in healthy subjects. A randomized, double‐blind, placebo‐controlled, dose‐escalation study was conducted in 50 healthy subjects. Each subject orally received LC51‐0255 (0.25, 0.5, 1, 2, or 4 mg) or its matching placebo in an 8:2 ratio. Blood and urine samples were collected to assess the PKs, and PDs was evaluated using peripheral ALC and 24‐h hourly heart rate data. Safety and tolerability were assessed by monitoring treatment emergent adverse events (TEAEs), vital signs, 12‐lead electrocardiogram (ECG), continuous 24‐h ECG (via Holter monitoring), clinical laboratory tests, ophthalmologic tests, pulmonary function tests, and physical examinations. A single dose of LC51‐0255 reduced ALC and heart rate in a reversible and dose‐dependent manner. Systemic exposure of LC51‐0255 increased dose‐dependently and its half‐life ranged from 72.2 to 134.0 h. ALC and the systemic exposure of LC51‐0255 seemed to be negatively correlated. LC51‐0255 was well‐tolerated up to 2 mg, and the most common TEAE was bradycardia. The results of this study suggest that LC51‐0255 can be developed into a beneficial treatment option for autoimmune disease.

Ozanimod as Induction and Maintenance Therapy for Ulcerative Colitis

BACKGROUND

Ozanimod, a selective sphingosine-1-phosphate receptor modulator, is under investigation for the treatment of inflammatory bowel disease.

METHODS

We conducted a phase 3, multicenter, randomized, double-blind, placebo-controlled trial of ozanimod as induction and maintenance therapy in patients with moderately to severely active ulcerative colitis. In the 10-week induction period, patients in cohort 1 were assigned to receive oral ozanimod hydrochloride at a dose of 1 mg (equivalent to 0.92 mg of ozanimod) or placebo once daily in a double-blind manner, and patients in cohort 2 received open-label ozanimod at the same daily dose. At 10 weeks, patients with a clinical response to ozanimod in either cohort underwent randomization again to receive double-blind ozanimod or placebo for the maintenance period (through week 52). The primary end point for both periods was the percentage of patients with clinical remission, as assessed with the three-component Mayo score. Key secondary clinical, endoscopic, and histologic end points were evaluated with the use of ranked, hierarchical testing. Safety was also assessed.

RESULTS

In the induction period, 645 patients were included in cohort 1 and 367 in cohort 2; a total of 457 patients were included in the maintenance period. The incidence of clinical remission was significantly higher among patients who received ozanimod than among those who received placebo during both induction (18.4% vs. 6.0%, P<0.001) and maintenance (37.0% vs. 18.5% [among patients with a response at week 10], P<0.001). The incidence of clinical response was also significantly higher with ozanimod than with placebo during induction (47.8% vs. 25.9%, P<0.001) and maintenance (60.0% vs. 41.0%, P<0.001). All other key secondary end points were significantly improved with ozanimod as compared with placebo in both periods. The incidence of infection (of any severity) with ozanimod was similar to that with placebo during induction and higher than that with placebo during maintenance. Serious infection occurred in less than 2% of the patients in each group during the 52-week trial. Elevated liver aminotransferase levels were more common with ozanimod.

CONCLUSIONS

Ozanimod was more effective than placebo as induction and maintenance therapy in patients with moderately to severely active ulcerative colitis. (Funded by Bristol Myers Squibb; True North ClinicalTrials.gov number, NCT02435992.).

Targeting Sphingosine-1-Phosphate Signaling in Immune-Mediated Diseases: Beyond Multiple Sclerosis

Sphingosine-1-phosphate (S1P) is a bioactive lipid metabolite that exerts its actions by engaging 5 G-protein-coupled receptors (S1PR1-S1PR5). S1P receptors are involved in several cellular and physiological events, including lymphocyte/hematopoietic cell trafficking. An S1P gradient (low in tissues, high in blood), maintained by synthetic and degradative enzymes, regulates lymphocyte trafficking. Because lymphocytes live long (which is critical for adaptive immunity) and recirculate thousands of times, the S1P-S1PR pathway is involved in the pathogenesis of immune-mediated diseases. The S1PR1 modulators lead to receptor internalization, subsequent ubiquitination, and proteasome degradation, which renders lymphocytes incapable of following the S1P gradient and prevents their access to inflammation sites. These drugs might also block lymphocyte egress from lymph nodes by inhibiting transendothelial migration. Targeting S1PRs as a therapeutic strategy was first employed for multiple sclerosis (MS), and four S1P modulators (fingolimod, siponimod, ozanimod, and ponesimod) are currently approved for its treatment. New S1PR modulators are under clinical development for MS, and their uses are being evaluated to treat other immune-mediated diseases, including inflammatory bowel disease (IBD), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and psoriasis. A clinical trial in patients with COVID-19 treated with ozanimod is ongoing. Ozanimod and etrasimod have shown promising results in IBD; while in phase 2 clinical trials, ponesimod has shown improvement in 77% of the patients with psoriasis. Cenerimod and amiselimod have been tested in SLE patients. Fingolimod, etrasimod, and IMMH001 have shown efficacy in RA preclinical studies. Concerns relating to S1PR modulators are leukopenia, anemia, transaminase elevation, macular edema, teratogenicity, pulmonary disorders, infections, and cardiovascular events. Furthermore, S1PR modulators exhibit different pharmacokinetics; a well-established first-dose event associated with S1PR modulators can be mitigated by gradual up-titration. In conclusion, S1P modulators represent a novel and promising therapeutic strategy for immune-mediated diseases.

Ponesimod: First Approval

Ponesimod (PONVORY™) is an orally administered selective sphingosine-1-phosphate (S1P) receptor 1 (S1P₁) agonist being developed by the Janssen Pharmaceutical Companies of Johnson & Johnson for the treatment of multiple sclerosis (MS). Based on the results of the phase III OPTIMUM trial, ponesimod was recently approved in the USA for the treatment of relapsing forms of MS and has received a positive CHMP opinion in the EU for this indication. This article summarizes the milestones in the development of ponesimod leading to this first US approval.

An Exposure-Response Analysis of the Clinical Efficacy of Ponesimod in a Randomized Phase II Study in Patients with Multiple Sclerosis

BACKGROUND AND OBJECTIVE

Ponesimod is a sphingosphine-1-phosphate receptor modulator being developed for the treatment of multiple sclerosis. The effects of disease-modifying treatments on magnetic resonance imaging (MRI) lesions in relapsing multiple sclerosis accurately predict effects on clinical relapses, therefore MRI lesion counts are generally accepted efficacy endpoints in phase II clinical studies of multiple sclerosis disease-modifying treatments. Here, we characterize the effect of ponesimod systemic exposure on the cumulative number of T1 gadolinium-enhancing (Gd+) lesions and the annualized relapse rate in a phase IIb study.

METHODS

This study assessed the cumulative number of new Gd+ lesions on T1-weighted MRI scans (primary endpoint) at weeks 12, 16, 20, and 24 and the annualized relapse rate (secondary endpoint). The effect of the demographic and prognostic covariates of sex, age, weight, T1 Gd+ lesions at baseline, and Expanded Disability Status Scale score at baseline were explored. Analyses were performed using NONMEM, Version 7.3.0 (ICON plc).

RESULTS

An increase in ponesimod exposure led to a statistically significant decrease in the cumulative T1 Gd+ lesions on MRI from week 12 to 24 of treatment. Increasing the ponesimod daily dose beyond 20 mg did not provide significant additional  benefits. Sex, age, T1 Gd+ lesions at baseline, and Expanded Disability Status Scale score at baseline were associated with a higher number of new cumulative T1 Gd+ from week 12 to 24 of treatment.

CONCLUSIONS

This analysis shows a relationship between ponesimod exposure and the cumulative number of new T1 Gd+ lesions. Sex, age, T1 Gd+ lesions at baseline, and Expanded Disability Status Score at baseline were not found to be importantly associated with the magnitude of ponesimod effect, and consequently, there is no indication from these analyses that dosage adjustments based on the explored covariates are warranted.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01006265, registration date 1 November, 2009.

Effect of Ponesimod Exposure on Total Lymphocyte Dynamics in Patients with Multiple Sclerosis

OBJECTIVE

The aim of this study was to characterize the relationship between ponesimod plasma concentrations and the temporal evolution of lymphocyte counts in multiple sclerosis (MS) patients.

METHODS

Population pharmacokinetic (PK) and PK/pharmacodynamic (PD) models were developed using data from phase I, II, and III trials, and the impact of clinically relevant covariates on PK and PD parameters was assessed. Simulations were conducted to evaluate the maximal lymphocyte count reduction after ponesimod treatment, and the time required for total lymphocyte counts to return to normal values after treatment interruption.

RESULTS

In MS patients, ponesimod PK were characterized by a low mean apparent plasma clearance (5.52 L/h) and a moderate mean apparent volume of distribution at steady state (239 L). The model developed indicated that none of the evaluated covariates (age, sex, formulation, food, body weight, clinical condition, and renal impairment) had a clinically relevant impact on the PK/PD parameters. In MS patients, total lymphocyte counts were characterized by a maximum reduction of 88.0% and a half maximal inhibitory concentration (IC₅₀) of 54.9 ng/mL. Simulations indicated that in patients with normal hepatic function treated with ponesimod 20 mg daily, total lymphocyte counts were reduced to 41% of baseline at trough. After stopping treatment, lymphocyte counts were restored to normal levels within one week.

CONCLUSIONS

The population PK/PD model well-characterized the PK of ponesimod and the time course of total lymphocyte counts in MS patients. Additionally, none of the evaluated covariates had a clinically relevant impact. This should be taken into consideration when assessing the risk of infection, administration of live-attenuated vaccines, and concomitant use of immunosuppressants.

Ponesimod modulates the Th1/Th17/Treg cell balance and ameliorates disease in experimental autoimmune encephalomyelitis

Sphingosine-1-phosphate receptor 1 (S1P1) plays an important role in autoimmune disease. Here, we evaluated whether ponesimod, an S1P1 modulator, affects inflammation in experimental autoimmune encephalomyelitis (EAE) and investigated Th1/Th2/Th17/Treg cell subsets. Ponesimod treatment ameliorated EAE and alleviated inflammatory infiltration. Compared with untreated EAE, ponesimod-treated mice had lower Th1 and Th17 cell numbers and higher Treg cell numbers; their IFN-γ, T-bet, IL-17, and RORγt levels as well as their pmTOR/mTOR ratio were diminished, while their TGF-β and Foxp3 levels were enhanced. These results suggest that ponesimod modulates the Th1/Th17/Treg balance and regulates the mTOR pathway.

Sphingosine 1-Phosphate Receptor Modulators for Multiple Sclerosis

Fingolimod (Gilenya) received regulatory approval from the US FDA in 2010 as the first-in-class sphingosine 1-phosphate (S1P) receptor (S1PR) modulator and was the first oral disease-modifying therapy (DMT) used for the treatment of the relapsing forms of multiple sclerosis (MS). Development of this new class of therapeutic compounds has continued to be a pharmacological goal of high interest in clinical trials for treatment of various autoimmune disorders, including MS. S1P is a physiologic signaling molecule that acts as a ligand for a group of cell surface receptors. S1PRs are expressed on various body tissues and regulate diverse physiological and pathological cellular responses involved in innate and adaptive immune, cardiovascular, and neurological functions. Subtype 1 of the S1PR (S1PR₁) is expressed on the cell surface of lymphocytes, which are well known for their major role in MS pathogenesis and play an important regulatory role in the egress of lymphocytes from lymphoid organs to the lymphatic circulation. Thus, S1PR₁-directed pharmacological interventions aim to modulate its role in immune cell trafficking through sequestration of autoreactive lymphocytes in the lymphoid organs to reduce their recirculation and subsequent infiltration into the central nervous system. Indeed, receptor subtype selectivity for S1PR₁ is theoretically favored to minimize safety concerns related to interaction with other S1PR subtypes. Improved understanding of fingolimod's mechanism of action has provided strategies for the development of the more selective second-generation S1PR modulators. This selectivity serves to reduce the most important safety concern regarding cardiac-related side effects, such as bradycardia, which requires prolonged first-dose monitoring. It has led to the generation of smaller molecules with shorter half-lives, improved onset of action with no requirement for phosphorylation for activation, and preserved efficacy. The shorter half-lives of the second-generation agents allow for more rapid reversal of their pharmacological effects following treatment discontinuation. This may be beneficial in addressing further treatment-related complications in case of adverse events, managing serious or opportunistic infections such as progressive multifocal leukoencephalopathy, and eliminating the drug in pregnancies. In March 2019, a breakthrough in MS treatment was achieved with the FDA approval for the second S1PR modulator, siponimod (Mayzent), for both active secondary progressive MS and relapsing-remitting MS. This was the first oral DMT specifically approved for active forms of secondary progressive MS. Furthermore, ozanimod received FDA approval in March 2020 for treatment of relapsing forms of MS, followed by subsequent approvals from Health Canada and the European Commission. Other second-generation selective S1PR modulators that have been tested for MS, with statistically significant data from phase II and phase III clinical studies, include ponesimod (ACT-128800), ceralifimod (ONO-4641), and amiselimod (MT-1303). This review covers the available data about the mechanisms of action, pharmacodynamics and kinetics, efficacy, safety, and tolerability of the various S1PR modulators for patients with relapsing-remitting, secondary progressive, and, for fingolimod, primary progressive MS.

Sphingosine 1-phosphate Receptor Modulator Therapy for Multiple Sclerosis: Differential Downstream Receptor Signalling and Clinical Profile Effects

Lysophospholipids are a class of bioactive lipid molecules that produce their effects through various G protein-coupled receptors (GPCRs). Sphingosine 1-phosphate (S1P) is perhaps the most studied lysophospholipid and has a role in a wide range of physiological and pathophysiological events, via signalling through five distinct GPCR subtypes, S1PR1 to S1PR5. Previous and continuing investigation of the S1P pathway has led to the approval of three S1PR modulators, fingolimod, siponimod and ozanimod, as medicines for patients with multiple sclerosis (MS), as well as the identification of new S1PR modulators currently in clinical development, including ponesimod and etrasimod. S1PR modulators have complex effects on S1PRs, in some cases acting both as traditional agonists as well as agonists that produce functional antagonism. S1PR subtype specificity influences their downstream effects, including aspects of their benefit:risk profile. Some S1PR modulators are prodrugs, which require metabolic modification such as phosphorylation via sphingosine kinases, resulting in different pharmacokinetics and bioavailability, contrasting with others that are direct modulators of the receptors. The complex interplay of these characteristics dictates the clinical profile of S1PR modulators. This review focuses on the S1P pathway, the characteristics and S1PR binding profiles of S1PR modulators, the mechanisms of action of S1PR modulators with regard to immune cell trafficking and neuroprotection in MS, together with a summary of the clinical effectiveness of the S1PR modulators that are approved or in late-stage development for patients with MS. Sphingosine 1-phosphate receptor modulator therapy for multiple sclerosis: differential downstream receptor signalling and clinical profile effects (MP4 65540 kb).

Population Pharmacokinetic Analysis of BMS-986166, a Novel Selective Sphingosine-1-Phosphate-1 Receptor Modulator, and Exposure-Response Assessment of Lymphocyte Counts and Heart Rate in Healthy Participants

Sphingosine‐1‐phosphate (S1P) binding to the S1P‐1 receptor (S1P1R) controls the egress of lymphocytes from lymphoid organs and targets modulation of immune responses in autoimmune diseases. Pharmacologic modulation of S1P receptors has been linked to heart rate reduction. BMS‐986166, a prodrug of the active phosphorylated metabolite BMS‐986166‐P, presents an improved cardiac safety profile in preclinical studies compared to other S1P1R modulators. The pharmacokinetics, safety, and pharmacodynamics of BMS‐986166 versus placebo after single (0.75–5.0 mg) and repeated (0.25–1.5 mg/day) oral administration were assessed in healthy participants after a 1‐day lead‐in placebo period. A population model was developed to jointly describe BMS‐986166 and BMS‐986166‐P pharmacokinetics and predict individual exposures. Inhibitory sigmoid models described the relationships between average daily BMS‐986166‐P concentrations and nadir of time‐matched (day –1) placebo‐corrected heart rate on day 1 (nDDHR, where DD represents ∆∆) and nadir of absolute lymphocyte count (nALC). Predicted decreases in nDDHR and nALC were 9 bpm and 20% following placebo, with maximum decreases of 10 bpm in nDDHR due to drug effect, and approximately 80% in nALC due to drug and placebo. A 0.5‐mg/day dose regimen achieves the target 65% reduction in nALC associated with a 2‐bpm decrease in nDDHR over placebo.

Sphingosine-1-Phosphate: Its Pharmacological Regulation and the Treatment of Multiple Sclerosis: A Review Article

Sphingosine-1-phosphate (S1P), via its G-protein-coupled receptors, is a signaling molecule with important regulatory properties on numerous, widely varied cell types. Five S1P receptors (S1PR1-5) have been identified, each with effects determined by their unique G-protein-driven downstream pathways. The discovery that lymphocyte egress from peripheral lymphoid organs is promoted by S1P via S1PR-1 stimulation led to the development of pharmacological agents which are S1PR antagonists. These agents promote lymphocyte sequestration and reduce lymphocyte-driven inflammatory damage of the central nervous system (CNS) in animal models, encouraging their examination of efficacy in the treatment of multiple sclerosis (MS). Preclinical research has also demonstrated direct protective effects of S1PR antagonists within the CNS, by modulation of S1PRs, particularly S1PR-1 and S1PR-5, and possibly S1PR-2, independent of effects upon lymphocytes. Three of these agents, fingolimod, siponimod and ozanimod have been approved, and ponesimod has been submitted for regulatory approval. In patients with MS, these agents reduce relapse risk, sustained disability progression, magnetic resonance imaging markers of disease activity, and whole brain and/or cortical and deep gray matter atrophy. Future opportunities in the development of more selective and intracellular S1PR-driven downstream pathway modulators may expand the breadth of agents to treat MS.

Siponimod in the treatment of multiple sclerosis

Introduction: Multiple sclerosis (MS) causes focal lesions of immune-mediated demyelinating events followed by slow progressive accumulation of disability. Over the past 2 decades, multiple medications have been studied and approved for use in MS. Most of these agents work by modulating or suppressing the peripheral immune system. Siponimod is a newer-generation sphingosine 1 phosphate (S1P) receptor modulator that internalizes S1P1 receptors, thereby inhibiting efflux of lymphocytes from lymph nodes and thymus. There are promising data suggesting that it may also have a direct neuroprotective property independent of peripheral lymphocytopenia.Areas covered: We reviewed the pharmacology and the clinical and radiological effects of siponimod.Expert opinion: The selective effect of siponimod on the S1P1 and S1P5 receptors offers a favorable side-effect profile and transient bradycardia can be avoided by dose titration. A phase-II study showed that siponomod has dose-dependent beneficial effects in patients with relapsing remitting disease. The results of a phase-III study suggest that siponimod may be beneficial in secondary progressive MS, at least in patients with disease activity.

The Case for an Unblinded Modeler in Early Clinical Development

The current trend for clinical pharmacology is toward more complex studies (eg, umbrella protocols covering single and multiple ascending doses, food effect, metabolism pathways), requiring many decisions to be made during their conduct. This article discusses guidance of such early clinical studies by modeling and simulation. The ability to make use of all available information each time new data become available during the study requires the modeling scientist to be unblinded. This must of course not jeopardize the blinding of the clinical team, and this article discusses how unblinding can be prevented. Although modeling and simulation are established for guidance of the drug development process overall, they are not frequently used for guidance on a small scale, that is, during studies with the largest uncertainty, the first-in-human studies. Application of a quantitative model backbone makes early clinical drug development a more efficient process and provides additional safety for healthy subjects and patients. Real clinical impact is illustrated by 3 case studies that show different contributions from unblinded modeling: dose escalation based on safety data, modeling and predicting with explicit incorporation of in vitro data, and dose escalation supported by unblinded analysis of adverse event data, which resulted in new insights of the clinical team without being unblinded and made it possible to proceed with dose escalation and to extend the study with an up-titration group.

Cardiodynamic Interactions between Two S1P1 Receptor Modulators in an Experimental Clinical Setting: Different Pharmacokinetic Properties as an Opportunity to Mitigate First-Dose Heart Rate Effects

A decrease in heart rate (HR) is a well-established first-dose effect of sphingosine-1-phosphate subtype 1 receptor (S1P1R) modulators. For compounds with a short half-life (t_1/2), this can be mitigated by gradual up-titration to therapeutic doses, whereas this is not required for compounds with a long t_1/2 due to the less pronounced first-dose-related negative chronotropic effects. Based on this conceptual framework, this mechanistic study investigated whether first-dose HR effects of ponesimod (t_1/2 ~32 h) can be mitigated by prior administration of cenerimod (t_1/2 ~415 h). Healthy subjects (n = 12) were randomly assigned to active or placebo (2:1 ratio). Active treatment consisted of a single dose of 10 mg ponesimod on Day 1, 18, and 37 and multiple-dose administration of 2 mg once daily cenerimod (Day 9-36). Placebos of cenerimod and ponesimod were used as reference treatment. Cardiodynamic parameters were derived from 24 h Holter electrocardiogram (ECG) assessments on Day 1, 9, 10, 18, 36, and 37. Ponesimod (10 mg) alone triggered a transient mean decrease from baseline in hourly mean HR of 17 bpm. In contrast, decreases of 5.0 and 4.8 bpm were observed when ponesimod was given at near half steady-state (Day 18) or steady-state (Day 37) cenerimod, respectively. Hourly mean HR decreased after first administration of cenerimod and placebo was 7.4 and 4.0 bpm, respectively. Treatment with ponesimod and cenerimod alone or in combination was safe and tolerated. First-dose-related negative chronotropic effects of ponesimod were less pronounced when administered after initiation of cenerimod suggesting mitigation of this class-related liability.

Benefit-Risk Profile of Sphingosine-1-Phosphate Receptor Modulators in Relapsing and Secondary Progressive Multiple Sclerosis

Since the approval of fingolimod, several selective sphingosine-1-phosphate receptor modulators have entered clinical development for multiple sclerosis. However, side effects can occur with sphingosine-1-phosphate receptor modulators. By considering short-term data across the drug class and longer term fingolimod data, we aim to highlight the potential of sphingosine-1-phosphate receptor modulators in multiple sclerosis, while offering reassurance that their benefit–risk profiles are suitable for long-term therapy. Short-term fingolimod studies demonstrated the efficacy of this drug class, showed that cardiac events upon first-dose administration are transient and manageable, and showed that serious adverse events are rare. Early-phase studies of selective sphingosine-1-phosphate receptor modulators also show efficacy with a similar or improved safety profile, and treatment initiation effects were reduced with dose titration. Longer term fingolimod studies demonstrated sustained efficacy and raised no new safety concerns, with no increases in macular edema, infection, or malignancy rates. Switch studies identified no safety concerns and greater patient satisfaction and persistence with fingolimod when switching from injectable therapies with no washout period. Better outcomes were seen with short than with long washouts when switching from natalizumab. The specific immunomodulatory effects of sphingosine-1-phosphate receptor modulators are consistent with the low observed rates of long-term, drug-related adverse effects with fingolimod. Short-term data for selective sphingosine-1-phosphate receptor modulators support their potential effectiveness in multiple sclerosis, and improved side-effect profiles may widen patient access to this drug class. The long-term safety, tolerability, and persistence profiles of fingolimod should reassure clinicians that sphingosine-1-phosphate receptor modulators are likely to be suitable for the long-term treatment of multiple sclerosis.

Ozanimod for the treatment of relapsing remitting multiple sclerosis

INTRODUCTION

Ozanimod is a selective sphingosine 1-phosphate receptor 1 and 5 modulator under development by Celgene, for the treatment of relapsing remitting multiple sclerosis. Extensive clinical experience has become available for the related compound fingolimod, favoring the sphingosine 1-phosphate therapeutic concept. Off-target effects have been attributed to its low receptor specificity and have prompted the development of next generation sphingosine 1-phosphate receptor modulators. Areas covered: The authors evaluate the literature of ozanimod, using the PubMed database as well as repositories of the European Committee for Treatment and Research in Multiple Sclerosis and the American and European Academy of Neurology. Specifically, the authors cover and discuss the preclinical data on ozanimod, pharmacokinetics and dynamics, and data on efficacy and safety from the pivotal trials. Expert opinion: Superiority of ozanimod over intramuscular interferon β-1a with regard to reduction in annualized relapse rate and magnetic resonance imaging outcomes has been shown in two phase III trials. The beneficial effect on brain volume and gray matter loss are encouraging and in line with data on other newer immunomodulators. Ozanimod is a valuable contribution to the therapeutic armamentarium in MS, although the effect on disability progression is unclear and requires further investigations.

An update on sphingosine-1-phosphate receptor 1 modulators

Sphingolipids represent an essential class of lipids found in all eukaryotes, and strongly influence cellular signal transduction. Autoimmune diseases like asthma and multiple sclerosis (MS) are mediated by the sphingosine-1-phosphate receptor 1 (S1P₁) to express a variety of symptoms and disease patterns. Inspired by its natural substrate, an array of artificial sphingolipid derivatives has been developed to target this specific G protein-coupled receptor (GPCR) in an attempt to suppress autoimmune disorders. FTY720, also known as fingolimod, is the first oral disease-modifying therapy for MS on the market. In pursuit of improved stability, bioavailability, and efficiency, structural analogues of this initial prodrug have emerged over time. This review covers a brief introduction to the sphingolipid metabolism, the mechanism of action on S1P₁, and an updated overview of synthetic sphingosine S1P₁ agonists.

S1PR3 Mediates Itch and Pain via Distinct TRP Channel-Dependent Pathways

Sphingosine 1-phosphate (S1P) is a bioactive signaling lipid associated with a variety of chronic pain and itch disorders. S1P signaling has been linked to cutaneous pain, but its role in itch has not yet been studied. Here, we find that S1P triggers itch and pain in male mice in a concentration-dependent manner, with low levels triggering acute itch alone and high levels triggering both pain and itch. Ca²⁺ imaging and electrophysiological experiments revealed that S1P signals via S1P receptor 3 (S1PR3) and TRPA1 in a subset of pruriceptors and via S1PR3 and TRPV1 in a subset of heat nociceptors. Consistent with these findings, S1P-evoked itch behaviors are selectively lost in mice lacking TRPA1, whereas S1P-evoked acute pain and heat hypersensitivity are selectively lost in mice lacking TRPV1. We conclude that S1P acts via different cellular and molecular mechanisms to trigger itch and pain. Our discovery elucidates the diverse roles that S1P signaling plays in somatosensation and provides insight into how itch and pain are discriminated in the periphery.SIGNIFICANCE STATEMENT Itch and pain are major health problems with few effective treatments. Here, we show that the proinflammatory lipid sphingosine 1-phosphate (S1P) and its receptor, S1P receptor 3 (S1PR3), trigger itch and pain behaviors via distinct molecular and cellular mechanisms. Our results provide a detailed understanding of the roles that S1P and S1PR3 play in somatosensation, highlighting their potential as targets for analgesics and antipruritics, and provide new insight into the mechanistic underpinnings of itch versus pain discrimination in the periphery.

Cardiac Safety of Ozanimod, a Novel Sphingosine-1-Phosphate Receptor Modulator: Results of a Thorough QT/QTc Study

Ozanimod is a novel, selective, oral sphingosine-1-phosphate (1 and 5) receptor modulator in development for multiple sclerosis and inflammatory bowel disease. This randomized, double-blind, placebo-controlled, positive-controlled, parallel-group thorough QT study characterized the effects of ozanimod on cardiac repolarization in healthy subjects. Eligible subjects were randomized to 1 of 2 groups: ozanimod (escalated from 0.25 to 2 mg over 14 days) or placebo (for 14 days). A single dose of moxifloxacin 400 mg or placebo was administered on days 2 and 17. The primary end point was the time-matched, placebo-corrected, baseline-adjusted mean QTcF (ΔΔQTcF). A total of 113/124 (91.1%) subjects completed the study. The upper limits of the 2-sided 90% confidence intervals for ΔΔQTcF for both ozanimod 1 and 2 mg were below the 10-millisecond regulatory threshold. No QTcF >480 milliseconds or postdose change in QTcF of >60 milliseconds was observed. There was no evidence of a positive relationship between concentrations of ozanimod and its active metabolites and ΔΔQTcF. Although ozanimod blunted the observed diurnal increase in heart rate, excursions below predose heart rates were no greater than with placebo. Results demonstrate that ozanimod does not prolong the QTc interval or cause clinically significant bradycardia, supporting ozanimod's evolving favorable cardiac safety profile.

Recent Advances in the Treatment for Multiple Sclerosis; Current New Drugs Specific for Multiple Sclerosis

Since the first approved parenteral drug for the treatment of multiple sclerosis (MS) in 1993 (interferon [IFN] beta, and later glatiramer acetate [GA]), today there are both parenteral and oral treatment options for MS. After IFN beta preparations, glatiramer acetate was developed; and, until the approval of natalizumab in 2006, those dominated the treatment of MS. Later on, among oral drug options, cladribine made a promising entry; however, due to safety concerns, it was withdrawn soon. Afterwards, with the understanding of the role of sphingosine-1 phosphate (S1P) receptors in the pathogenesis of MS, fingolimod was approved in 2010, which was followed by other oral agents such as teriflunomide and dimethyl fumarate. Recently newer IV treatment options such as alemtuzumab, rituximab and ocrelizumab have widened the treatment arena. Recently, after submitting new efficacy and safety data, cladribine was approved for MS by EMA, in 2017. Moreover, seven years after its rejection due to safety reasons, in August 2018 FDA accepted to re-evaluate the data of cladribine as a treatment option for relapsing remitting MS (RRMS). Another oral treatment option, Laquinimod, was not approved because it could not be shown to slow disability progression despite favourable effect in relapsing MS. Newer generation S1P receptor modulators are being investigated currently, and they are expected to come into the treatment arena soon. In this article, mechanisms of actions, clinical trial results, and side effects of the newer drugs used for MS, are reviewed. IFN beta and glatiramer acetate were not included since they have clinical experience nearing 30 years.

Pharmacokinetics, Pharmacodynamics, Tolerability, and Food Effect of Cenerimod, a Selective S1P₁ Receptor Modulator in Healthy Subjects

The pharmacokinetics, pharmacodynamics, tolerability, and food effect of cenerimod, a potent sphingosine-1-phosphate subtype 1 receptor modulator, were investigated in three sub-studies. Two double-blind, placebo-controlled, randomised studies in healthy male subjects were performed. Cenerimod was administered either as single dose (1, 3, 10 or 25 mg; Study 1) or once daily for 35 days (0.5, 1, 2 or 4 mg; Study 2). A two-period cross-over, open-label study was performed to assess the food effect (1 mg, Study 3). The pharmacokinetic profile of cenerimod was characterised by a t_max of 5.0–6.2 h. Terminal half-life after single and multiple doses ranged from 170 to 199 h and 283 to 539 h, respectively. Food had no relevant effect on the pharmacokinetics of cenerimod. A dose-dependent decrease in lymphocyte count was observed after initiation of cenerimod and reached a plateau (maximum change from baseline: −64%) after 20–23 days of treatment. Lymphocyte counts returned to baseline values at end-of-study examination. One serious adverse event of circulatory collapse (25 mg dose group, maximum tolerated dose: 10 mg) and adverse events of mild-to-moderate intensity were reported. Treatment initiation was associated with transient decreases in heart rate and blood pressure at doses >1 and ≥10 mg, respectively.

Modeling clinical efficacy of the S1P receptor modulator ponesimod in psoriasis

BACKGROUND

Ponesimod is currently the only S1P receptor modulator studied in psoriasis. In a dose-finding study, the active doses showed similar efficacy.

OBJECTIVE

Prediction of efficacy at lower doses to aid clinical phase 3 planning with respect to dose selection, duration of treatment, and patient inclusion criteria based on pharma-co-kinetic/pharmacodynamic (PK/PD) modeling and simulation.

METHODS

The dose-finding study treated 326 patients (67 on placebo, 126 on 20mg, and 133 on 40mg) over 16 weeks. PK/PD modeling of steady-state trough concentrations and longitudinal PASI scores was employed to characterize data and simulate scenarios.

RESULTS

PASI score continually decreased with time on ponesimod treatment, reaching a plateau at 16 weeks. Absolute and relative (percent) PASI score change was larger in patients with higher PASI score at baseline. Doses below 10mg were predicted to show lower efficacy than doses of 10mg and higher.

CONCLUSION

Concentration-response modeling was able to predict the efficacy of doses that were not studied. In psoriasis patients, a dose of 10mg (not administered in the study) was predicted to show efficacy similar to 20mg. Disease status (PASI score at baseline) as study inclusion criterion has pronounced influence on study outcome.

Impact of siponimod on vaccination response in a randomized, placebo-controlled study

OBJECTIVE

To evaluate effects of siponimod on response to T-cell-dependent (influenza) and T-cell-independent (pneumococcal polysaccharide vaccine [PPV-23]) vaccinations in healthy participants.

METHODS

In this double-blind, placebo-controlled, parallel-group study, each participant underwent a 7-week treatment period and received intramuscular injections of influenza and PPV-23 vaccines (day 21). Participants were randomized to 4 treatment groups (N = 30 each) and received placebo or siponimod 2 mg once daily in concomitant, interrupted, or preceding fashion. Individual response to vaccination was defined by a ≥4-fold (influenza) antibody titer increase and by a ≥2-fold increase in serotype-specific immunoglobulin (Ig) G concentrations (PPV-23) on day 28 vs baseline. Responder rates were compared using noninferiority analysis.

RESULTS

Mean influenza titers were similar to placebo in the preceding and interrupted groups but lower in the concomitant group. The proportion of participants with influenza titers ≥40 four weeks after vaccination (seroprotection) was similar to placebo across all groups and antigens. In each treatment group, response criteria were met for 3 of 4 antigens including H1N1 and H3N2. A noninferior response was determined in the context of preceding treatment but not interrupted or concomitant treatment. Regarding PPV-23, approximately 90%-100% of participants exhibited a ≥2-fold increase in IgG concentrations vs baseline. Noninferior responder rates were determined for each siponimod treatment group.

CONCLUSIONS

Siponimod treatment had no relevant effect on antibody response to PPV-23. European Medicines Agency response criteria were essentially met for influenza, but titers were lower on concomitant treatment. Overall, these data suggest that siponimod has limited effect on the efficacy of vaccinations with neoantigens.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that in healthy persons, siponimod had limited effect on the immune response following influenza or pneumococcal vaccinations.

Sphingosine 1-Phosphate Receptor Modulators for the Treatment of Multiple Sclerosis

Sphingosine 1-phosphate receptor (S1PR) modulators possess a unique mechanism of action in the treatment of multiple sclerosis (MS). Subtype 1 of the S1PR is expressed on the surface of lymphocytes and is important in regulating egression from lymph nodes. The S1PR modulators indirectly antagonize the receptor's function leading to sequestration of lymphocytes in the lymph nodes. Fingolimod was the first S1PR modulator to receive regulatory approval for relapsing-remitting MS after 2 phase III trials demonstrated potent efficacy, safety, and tolerability. Fingolimod can cause undesirable effects as a result of its interaction with other S1PR subtypes, which are expressed in diverse tissues, including cardiac myocytes. As such, agents that more selectively target subtype 1 of the S1PR are of interest and are at various stages of development. These include ponesimod (ACT128800), siponimod (BAF312), ozanimod (RPC1063), ceralifimod (ONO-4641), GSK2018682, and MT-1303. Data from phase II trials and early results from phase III studies have been promising and will be presented in this review. Of special interest are results from the EXPAND study of siponimod, which suggest a potential role for S1PR modulators in secondary progressive MS.

Ponesimod, a selective sphingosine 1-phosphate (S1P1) receptor modulator for autoimmune diseases: review of clinical pharmacokinetics and drug disposition

1. Ponesimod, a selective sphingosine 1-phosphate (S1P₁) receptor modulator, is undergoing clinical development for the treatment of autoimmune diseases (multiple sclerosis/psoriasis). 2. Published literature data describing pharmacokinetic disposition of ponesimod were collected, reviewed and tabulated. 3. Across various clinical phase-I studies, ponesimod displayed consistent pharmacokinetics - relatively faster absorption peak time (approximately 2.5 h), elimination half-life of approximately 30 h and modest accumulation (2- to 2.6-fold). Ponesimod was extensively metabolized and two major metabolites were ACT-204426 and ACT-338375. 4. Extensive population pharmacokinetic-pharmacodynamic modeling has confirmed the therapeutic dose(s) for ponesimod to achieve the balance between safety (primarily heart rate) and efficacy using the maximum inhibition of the total lymphocytes as the pharmacodynamic marker. 5. None of the covariates (ethnicity, body weight, sex, diseased state including multiple sclerosis and psoriasis, food intake, formulation, etc.) examined in population pharmacokinetic model influenced the pharmacokinetics of ponesimod from a clinical relevance perspective. However, hepatic impairment (moderate/severe but not mild), profoundly influenced its disposition; and therefore, would necessitate dosage adjustment of ponesimod in clinical therapy. 6. Ponesimod has a favorable safety profile and pharmacokinetics, which will allow maximizing its ability to inhibit circulating lymphocytes in a given dosing regimen for treating autoimmune diseases.

Results From the First-in-Human Study With Ozanimod, a Novel, Selective Sphingosine-1-Phosphate Receptor Modulator

The sphingosine-1-phosphate 1 receptor (S1P_1R ) is expressed by lymphocytes, dendritic cells, and vascular endothelial cells and plays a role in the regulation of chronic inflammation and lymphocyte egress from peripheral lymphoid organs. Ozanimod is an oral selective modulator of S1P_1R and S1P_5R receptors in clinical development for the treatment of chronic immune-mediated, inflammatory diseases. This first-in-human study characterized the safety, pharmacokinetics (PK), and pharmacodynamics (PD) of ozanimod in 88 healthy volunteers using a range of single and multiple doses (7 and 28 days) and a dose-escalation regimen. Ozanimod was generally well tolerated up to a maximum single dose of 3 mg and multiple doses of 2 mg/d, with no severe adverse events (AEs) and no dose-limiting toxicities. The most common ozanimod-related AEs included headache, somnolence, dizziness, nausea, and fatigue. Ozanimod exhibited linear PK, high steady-state volume of distribution (73-101 L/kg), moderate oral clearance (204-227 L/h), and an elimination half-life of approximately 17 to 21 hours. Ozanimod produced a robust dose-dependent reduction in total peripheral lymphocytes, with a median decrease of 65% to 68% observed after 28 days of dosing at 1 and 1.5 mg/d, respectively. Ozanimod selectivity affected lymphocyte subtypes, causing marked decreases in cells expressing CCR7 and variable decreases in subsets lacking CCR7. A dose-dependent negative chronotropic effect was observed following the first dose, with the dose-escalation regimen attenuating the first-dose negative chronotropic effect. Ozanimod safety, PK, and PD properties support the once-daily regimens under clinical investigation.