Investigating the Mitoprotective Effects of S1P Receptor Modulators Ex Vivo Using a Novel Semi-Automated Live Imaging Set-Up.

In multiple sclerosis (MS), mitochondrial alterations appear to contribute to disease progression. The sphingosine-1-phosphate receptor modulator siponimod is approved for treating secondary progressive MS. Its preceding compound fingolimod was shown to prevent oxidative stress-induced alterations in mitochondrial morphology. Here, we assessed the effects of siponimod, compared to fingolimod, on neuronal mitochondria in oxidatively stressed hippocampal slices. We have also advanced the model of chronic organotypic hippocampal slices for live imaging, enabling semi-automated monitoring of mitochondrial alterations. The slices were prepared from B6.Cg-Tg(Thy1-CFP/COX8A)S2Lich/J mice that display fluorescent neuronal mitochondria. They were treated with hydrogen peroxide (oxidative stress paradigm) ± 1 nM siponimod or fingolimod for 24 h. Afterwards, mitochondrial dynamics were investigated. Under oxidative stress, the fraction of motile mitochondria decreased and mitochondria were shorter, smaller, and covered smaller distances. Siponimod partly prevented oxidatively induced alterations in mitochondrial morphology; for fingolimod, a similar trend was observed. Siponimod reduced the decrease in mitochondrial track displacement, while both compounds significantly increased track speed and preserved motility. The novel established imaging and analysis tools are suitable for assessing the dynamics of neuronal mitochondria ex vivo. Using these approaches, we showed that siponimod at 1 nM partially prevented oxidatively induced mitochondrial alterations in chronic brain slices.

The sphingosine-1-phosphate receptor modulator, FTY720, prevents the incidence of diabetes in Spontaneously Diabetic Torii rats.

The sphingosine-1-phosphate (S1P) receptor modulator regulates lymphocyte trafficking, resulting in its depletion from circulation, which ultimately causes immunosuppression. In this study, we investigated the preventive effect of fingolimod (FTY720) in the non-obese type 2 diabetic model, Spontaneously Diabetic Torii (SDT) rats. The S1P receptor modulator, FTY720 (0.3 mg/kg p.o.), was administered for 12 weeks to SDT rats from 5 to 17 weeks of age. Based on our findings, FTY720 could suppress the incidence of diabetes in SDT rats. Further, glucose intolerance was improved in FTY720-treated SDT rats at 14 weeks of age. Based on the haematological and histological analyses performed at 17 to 18 weeks of age, a decrease in lymphocytes and monocytes in the peripheral blood and a decrease in lymphocyte and atrophy in spleen occurred in the FTY720-treated SDT rats. Furthermore, the pancreatic changes, such as inflammation, atrophy, and fibrosis in islets observed in SDT rats were improved by FTY720 treatment. These findings suggest that the immunomodulatory effects of FTY720 reduced the pancreatic lesion in SDT rats, thereby demonstrating its preventive effect against diabetes. The development of diabetes in SDT rats is related to disorders of the immune system. However, the S1P receptor modulator may be useful for treating type 2 diabetes.

Two-year results from a phase 2 extension study of oral amiselimod in relapsing multiple sclerosis.

BACKGROUND: Amiselimod, an oral selective sphingosine-1-phosphate 1 receptor modulator, suppressed disease activity dose-dependently without clinically relevant bradyarrhythmia in a 24-week phase 2, placebo-controlled study in relapsing-remitting multiple sclerosis. OBJECTIVE: To assess safety and efficacy of amiselimod over 96 weeks. METHODS: After completing the core study, patients on amiselimod continued at the same dose, whereas those on placebo were randomised 1:1:1 to amiselimod 0.1, 0.2 or 0.4 mg for another 72 weeks. Most patients receiving 0.1 mg were re-randomised to 0.2 or 0.4 mg upon availability of the core study results. RESULTS: Of 415 patients randomised in the core study, 367 (88.4%) entered and 322 (77.6%) completed the extension. One or more adverse events were reported in 303 (82.6%) of 367 patients: 'headache', 'lymphocyte count decreased', 'nasopharyngitis' and 'MS relapse' were most common (14.7%-16.9%). No serious opportunistic infection, macular oedema or malignancy was reported and no bradyarrhythmia of clinical concern was observed by Holter or 12-lead electrocardiogram. The dose-dependent effect of amiselimod on clinical and magnetic resonance imaging-related outcomes from the core study was sustained in those continuing on amiselimod and similarly observed after switching to active drug. CONCLUSION: For up to 2 years of treatment, amiselimod was well tolerated and dose-dependently effective in controlling disease activity.

Evaluation of species difference in peripheral lymphocyte reduction effect of CS-0777, a sphingosine 1-phosphate receptor modulator, based on a pharmacokinetic/pharmacodynamic model analysis.

Pharmacokinetic (PK) and pharmacodynamic (PD) modeling was conducted for the reduction of peripheral lymphocytes after oral administration of CS-0777 to healthy rats, monkeys and experimental autoimmune encephalomyelitis (EAE) induced rats. The phosphorylated active metabolite of CS-0777, M1, is a selective sphingosine 1-phosphate receptor-1 modulator. A linear one- and two-compartment model with a reversible metabolism process characterized the time courses of CS-0777 and M1 concentrations in rats and monkeys, respectively. The relationship between lymphocyte counts and M1 concentrations in blood was well described by an indirect response model in all animals examined. An Imax of 0.815 and an IC50 of 6.58 nM in healthy rats, an Imax of 0.807 and an IC50 of 5.09 nM in the EAE rats, an Imax of 0.789 and an IC50 of 0.484 nM in monkeys were estimated by the indirect PD model. Since the IC50 values calculated in terms of the unbound plasma concentration in rats and monkeys were within a similar range, after correction of the IC50 in blood described above with the blood to plasma concentration ratio and the plasma free fraction of M1, it was revealed that there is no species difference in the essential activity of M1 against lymphocyte reduction. The sensitivity of the lymphocytes to M1 was not affected by the EAE status. Comparison of the simulated lymphocyte reduction in EAE rats after multiple dosing with CS-0777 and the actual EAE clinical scores implies that the significant suppressive effect on EAE did not require the elimination of all lymphocytes from the blood. Copyright © 2016 John Wiley & Sons, Ltd.

Five-year results from a phase 2 study of oral fingolimod in relapsing multiple sclerosis.

We present here results at 60 months (M), from the extension component of a phase 2, randomized, placebo-controlled, double-blind, six-month study evaluating oral fingolimod (1.25 mg or 5 mg daily) in relapsing multiple sclerosis. Placebo patients from the core study were re-randomized to fingolimod 1.25 mg or 5 mg in the extension. All patients received 1.25 mg fingolimod after the M24 visit. A total of 140/281 (49.8%) patients completed M60. Fingolimod treatment was associated with a low annualized relapse rate (0.2 relapses/ year), low MRI activity, and a modest rate of disability progression in those treated for five years. No new safety issues were reported.

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.

Judicious Use of Ozanimod for Ulcerative Colitis and Multiple Sclerosis.

Clinical trials have demonstrated the efficacy of ozanimod, an oral sphingosine-1-phosphate receptor modulator, for the treatment of moderate-to-severe ulcerative colitis. Infrequently does an opportunity present itself to use one drug for two simultaneous disease states, proving especially beneficial in the case of this patient intolerant of numerous established therapies for ulcerative colitis. This case report describes the successful use of ozanimod for both ulcerative colitis and multiple sclerosis, achieving clinical remission in both diseases.

Fingolimod Modulates the Gene Expression of Proteins Engaged in Inflammation and Amyloid-Beta Metabolism and Improves Exploratory and Anxiety-Like Behavior in Obese Mice.

Obesity is considered a risk factor for type 2 diabetes mellitus, which has become one of the most important health problems, and is also linked with memory and executive function decline. Sphingosine-1-phosphate (S1P) is a bioactive sphingolipid that regulates cell death/survival and the inflammatory response via its specific receptors (S1PRs). Since the role of S1P and S1PRs in obesity is rather obscure, we examined the effect of fingolimod (an S1PR modulator) on the expression profile of genes encoding S1PRs, sphingosine kinase 1 (Sphk1), proteins engaged in amyloid-beta (Aß) generation (ADAM10, BACE1, PSEN2), GSK3ß, proapoptotic Bax, and proinflammatory cytokines in the cortex and hippocampus of obese/prediabetic mouse brains. In addition, we observed behavioral changes. Our results revealed significantly elevated mRNA levels of Bace1, Psen2, Gsk3b, Sphk1, Bax, and proinflammatory cytokines, which were accompanied by downregulation of S1pr1 and sirtuin 1 in obese mice. Moreover, locomotor activity, spatially guided exploratory behavior, and object recognition were impaired. Simultaneously, fingolimod reversed alterations in the expressions of the cytokines, Bace1, Psen2, and Gsk3b that occurred in the brain, elevated S1pr3 mRNA levels, restored normal cognition-related behavior patterns, and exerted anxiolytic effects. The improvement in episodic and recognition memory observed in this animal model of obesity may suggest a beneficial effect of fingolimod on central nervous system function.

Disposition and Mass Balance of Etrasimod in Healthy Subjects and In Vitro Determination of the Enzymes Responsible for Its Oxidative Metabolism.

Etrasimod (APD334) is an investigational, once-daily, oral, selective sphingosine 1-phosphate receptor 1,4,5 modulator (S1P1,4,5 ) in development for treatment of various immune-mediated inflammatory disorders. The disposition and mass balance of a single 2-mg [14 C]etrasimod dose were evaluated in 8 healthy males. An in vitro study was also conducted to identify etrasimod's oxidative metabolizing enzymes. Peak concentrations of etrasimod and total radioactivity in plasma and whole blood were typically reached 4-7 hours postdose. Etrasimod constituted 49.3% of total radioactivity plasma exposure, with multiple minor/trace metabolites making up the remainder. Etrasimod was slowly cleared mainly via biotransformation, predominantly by oxidative metabolism, with unchanged etrasimod recovered in feces accounting for only 11.2% of the dose and none in urine. The mean apparent terminal half-lives of etrasimod and total radioactivity in plasma were 37.8 and 89.0 hours, respectively. Mean cumulative recovery of radioactivity in excreta over 336 hours was 86.9% of the dose, mostly in feces. The prevalent metabolites eliminated in feces were M3 (hydroxy-etrasimod) and M36 (oxy-etrasimod sulfate), accounting for 22.1% and 18.9% of the dose, respectively. From in vitro reaction phenotyping, the predominant enzymes involved in the oxidation of etrasimod were CYP2C8, CYP2C9, and CYP3A4, with minor contributions from CYP2C19 and CYP2J2.

Comparison of the safety and efficacy of fingolimod and tofacitinib in the zebrafish model of colitis.

BACKGROUND: Oral targeted small molecules, including sphingosine 1 phosphate receptor (S1PR) modulators and tyrosine kinase inhibitors (TKIs), seem to revolutionize the management of inflammatory bowel disease (IBD). To select the most effective treatment, there is an unmet need to comparatively study their mechanism of action, efficacy, and toxicity in the preclinical stage and further translate it into clinical practice. METHODS: Using 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced adult zebrafish colitis model, LC50 of fingolimod and tofacitinib were determined based on the acute toxicity test to compare aquatic toxicity potential. Subsequently, the efficacy of different concentrations of tofacitinib and fingolimod was compared using flow cytometry, qPCR, and histopathology analyses. RESULTS: TNBS significantly reduced the length of villi, and the number of goblet cells increased the level of TNF-α, MyD88, and NF-κB2, the thickness of villi and necrosis, and induced histopathological changes. All of these parameters were reversed almost dose-dependently with both medications, with the highest concentration of fingolimod being superior to other groups. Additionally, results from qPCR analysis suggested that these medications might suppress canonical and non-canonical NF-κB pathways by targeting toll-like receptors and MyD88. LC50 of tofacitinib and fingolimod was 0.9014 and 0.36 mg/L, respectively. Hence, both are in the cory 1 of the Global Harmonization System (GHS) aquatic toxicity and are toxic to adult zebrafish life. CONCLUSION: Given the better efficacy of fingolimod, it is worth translating the effectiveness and safety of S1PR modulators into IBD patients and comparing them with TKIs in head-to-head studies; albeit, their toxicity should not be overlooked.

Dose-dependent reduction of lymphocyte count and heart rate after multiple administration of LC51-0255, a novel sphingosine-1-phosphate receptor 1 modulator, in healthy subjects.

Aim: Sphingosine-1-phosphate receptor mediates the egress of lymphocytes from lymphoid organs, and its inhibition results in a decreased number of circulating lymphocytes. The aim of the current study was to investigate the safety and pharmacodynamic and pharmacokinetic characteristics of a novel sphingosine-1-phosphate receptor modulator, LC51-0255. Methods: A phase 1 randomized, double-blind, placebo-controlled, multiple dosing, dose-escalation study was conducted on healthy Korean male subjects. Results: After single and daily administration of LC51-0255 for 21 days, a dose-dependent decrease in lymphocyte count and heart rate was observed through 0.25-2 mg dose range of LC51-0255. The mean elimination half-life of LC51-0255 was 76-95 h. LC51-0255 was accumulated with a mean accumulation ratio of 5.17-6.64. During the study, LC51-0255 was generally well tolerated. The most common treatment-emergent adverse event was bradycardia. No clinically significant event of arrhythmia, including AV block, was observed. No clinically significant difference in blood pressure was observed between the dose groups. In other safety assessments, no clinically significant abnormalities were observed, except for bradycardia. Conclusion: Daily administration of LC51-0255 in the range of 0.25-2 mg resulted in a dose-dependent reduction of lymphocyte counts and heart rate. LC51-0255 is generally safe and well tolerated in healthy volunteers.

An Update for Pharmacologists on New Treatment Options for Inflammatory Bowel Disease: The Clinicians' Perspective.

The introduction of anti-tumor necrosis factor antibodies resulted in a considerable expansion of the options available for the treatment of inflammatory bowel disease. Unfortunately, approximately one third of treated patients do not respond to these modalities, and drug efficacy may be lost over time. These drugs are also associated with contraindications, adverse events, and intolerance. As such, there is an ongoing need for new therapeutic strategies. Despite several recent advances, including antibodies against pro-inflammatory cytokines and cell adhesion molecules, Janus kinase inhibitors, and modulators of sphingosine-1-phosphate receptors, not all problems associated with IBD have been solved. In this manuscript, we review the current state of development of several new treatment options. Ongoing evaluation will require specific proof of efficacy as well as direct comparisons with established treatments. Results from head-to-head comparisons are needed to provide clinicians with critical information on how to formulate effective therapeutic approaches for each patient.

Ozanimod to Treat Relapsing Forms of Multiple Sclerosis: A Comprehensive Review of Disease, Drug Efficacy and Side Effects.

Multiple sclerosis (MS) is a prevalent and debilitating neurologic condition characterized by widespread neurodegeneration and the formation of focal demyelinating plaques in the central nervous system. Current therapeutic options are complex and attempt to manage acute relapse, modify disease, and manage symptoms. Such therapies often prove insufficient alone and highlight the need for more targeted MS treatments with reduced systemic side effect profiles. Ozanimod is a novel S1P (sphingosine-1-phosphate) receptor modulator used for the treatment of clinically isolated syndrome, relapsing-remitting, and secondary progressive forms of multiple sclerosis. It selectively modulates S1P1 and S1P5 receptors to prevent autoreactive lymphocytes from entering the CNS where they can promote nerve damage and inflammation. Ozanimod was approved by the US Food and Drug Administration (US FDA) for the management of multiple sclerosis in March 2020 and has been proved to be both effective and well tolerated. Of note, ozanimod is associated with the following complications: increased risk of infections, liver injury, fetal risk, increased blood pressure, respiratory effects, macular edema, and posterior reversible encephalopathy syndrome, among others. Further investigation including head-to-head clinical trials is warranted to evaluate the efficacy of ozanimod compared with other S1P1 receptor modulators.

Long-term results from a phase 2 extension study of fingolimod at high and approved dose in relapsing multiple sclerosis.

Fingolimod safety and efficacy data in relapsing-remitting multiple sclerosis (RRMS) are available up to 5 years, from an extension of a randomized, placebo-controlled, double-blind, phase 2 study, at a dose higher (5.0/1.25 mg) than the approved dose of 0.5 mg. The objective of the study is to present the end-of-study data (>7 years) from the open-label extension of the phase 2 study. In the core phase (6 months), patients (N = 281) were randomized to placebo or fingolimod 1.25/5 mg. In the extension, placebo patients were randomized to fingolimod 1.25/5 mg. All patients received open-label 1.25 mg fingolimod after month 24 and 0.5 mg after month 60. Clinical visits were performed every 3 months, expanded disability status scale (EDSS) every 6 months and magnetic resonance imaging (MRI) annually. 122 (48.8%) patients completed the extension study; overall fingolimod exposure was 1230.7 patient-years. The most common (>10%) reasons for study discontinuation were adverse events (19.6%) and consent withdrawal (16.4%). Fingolimod treatment for >7 years was associated with sustained low clinical and MRI disease activity. Over 60% of patients remained relapse free and about 80% were free from any MRI activity. Overall annualized relapse rate was 0.18. Long-term fingolimod treatment was not associated with new safety concerns. Long-term fingolimod was well tolerated and associated with a sustained low level of disease activity.

Impact of prior treatment status and reasons for discontinuation on the efficacy and safety of fingolimod: Subgroup analyses of the Fingolimod Research Evaluating Effects of Daily Oral Therapy in Multiple Sclerosis (FREEDOMS) study.

BACKGROUND: Fingolimod is a once-daily, oral sphingosine 1-phosphate receptor modulator approved for the treatment of relapsing multiple sclerosis. OBJECTIVE: This post-hoc analysis of phase 3 FREEDOMS data assessed whether the effects of fingolimod are consistent among subgroups of patients defined by prior treatment history. METHODS: Annualized relapse rate and safety profile of treatment with fingolimod 0.5mg, 1.25mg, or placebo once-daily for 24 months were analyzed in 1272 relapsing multiple sclerosis patients, by subgroups based on disease-modifying therapy history (treatment-naive; prior interferon-ß or glatiramer acetate), reason for discontinuation of prior disease-modifying therapy (unsatisfactory therapeutic response or adverse events), and prior disease-modifying therapy duration. RESULTS: Both fingolimod doses significantly reduced annualized relapse rate in patients that received prior interferon-ß or glatiramer acetate, discontinued prior disease-modifying therapy owing to unsatisfactory therapeutic effect, were treatment-naive, or had prior disease-modifying therapy duration of >1-3 years (P≤0.0301 for all comparisons vs placebo). Fingolimod 1.25mg resulted in greater reductions in annualized relapse rate in patients that discontinued prior disease-modifying therapy for adverse events or had prior disease-modifying therapy duration of ≤1 year or >3 years (P≤0.0194 vs placebo). CONCLUSIONS: Fingolimod demonstrated similar efficacy in relapsing multiple sclerosis patients regardless of prior treatment history. Clinicaltrials.gov identifier: NCT00289978.

Effect of prior treatment status and reasons for discontinuation on the efficacy and safety of fingolimod vs. interferon ß-1a intramuscular: Subgroup analyses of the Trial Assessing Injectable Interferon vs. Fingolimod Oral in Relapsing-Remitting Multiple Sclerosis (TRANSFORMS).

BACKGROUND: Fingolimod demonstrated superior efficacy compared with interferon ß-1a intramuscular in relapsing multiple sclerosis. The impact of treatment history on fingolimod efficacy is unknown. OBJECTIVES: This post-hoc analysis of phase 3 TRANSFORMS data compared the efficacy and safety of fingolimod and interferon ß-1a intramuscular among patient subgroups defined by prior treatment history. METHODS: Annualized relapse rate and safety of once-daily oral fingolimod 0.5mg, 1.25mg, or once-weekly interferon ß-1a 30µg intramuscular for 12 months were analyzed in 1292 patients with relapsing multiple sclerosis according to prior disease-modifying therapy, reason for prior disease-modifying therapy discontinuation (adverse events or unsatisfactory therapeutic effect), and prior disease-modifying therapy duration. RESULTS: Compared with interferon ß-1a intramuscular, fingolimod 0.5mg significantly reduced annualized relapse rate in patients who were treatment naive, received prior interferon-ß treatment, discontinued prior disease-modifying therapy for unsatisfactory therapeutic effect, or had prior disease-modifying therapy duration of ≥1 year (P≤0.05, all comparisons). Similar trends were observed in patients with prior glatiramer acetate treatment. Significant reductions were also seen with fingolimod 1.25mg for treatment-naive and prior interferon-ß-treated patients. CONCLUSIONS: This analysis demonstrates superiority of fingolimod over interferon ß-1a intramuscular regardless of prior (interferon-ß) treatment and prior treatment efficacy and duration. ClinicalTrials.gov identifier: NCT00340834.

Tolerability and Pulmonary Pharmacodynamic Effects During Treatment Initiation of Once-Daily Oral Fingolimod in Subjects With Moderate Asthma.

Fingolimod, a first-in-class sphingosine 1-phosphate receptor modulator, is the first approved oral therapy for relapsing multiple sclerosis (MS). While treatment initiation of clinical dose of fingolimod (0.5 mg) does not affect pulmonary function, supra-therapeutic doses (≥5.0 mg) increased airway resistance. The aim of this double-blind, placebo-controlled, parallel group, 10-day study was to measure the effect of fingolimod on pulmonary function in otherwise healthy patients with moderate asthma. Subjects (n = 36) were randomized into four cohorts that received either fingolimod 0.5, 1.25, 2.5 mg, or placebo once daily for 10 days. Subjects in placebo and fingolimod 0.5 mg groups did not differ in FEV1 AUEC0-6 h , FEF25-75% AUEC0-6 h , or in short-acting beta (ß) 2 agonists (SABA, rescue bronchodilator) use. Subjects on higher doses of fingolimod showed a mild reduction in FEV1 AUEC0-6 h and FEF25-75% AUEC0-6 h and a significant sixfold increase in SABA use versus placebo. One subject had moderately severe, acute exacerbation of asthma after receiving the first dose of fingolimod 1.25 mg that quickly responded to inhaled SABA. The observed safety profile was consistent with previous reports. These results provide reassurance that moderately asthmatic MS individuals can start on fingolimod 0.5 mg therapy with minimal effects on pulmonary function and SABA use.