Selective Sphingosine 1-phosphate Research Articles

Safety and Efficacy of Long-Term Treatment with Ozanimod, an Oral S1P Receptor Modulator, in Moderate to Severe Ulcerative Colitis: Touchstone Extension

Introduction: Ozanimod (RPC1063) is an oral, selective sphingosine 1-phosphate (S1P) 1 and 5 receptor modulator in clinical development for the treatment of Inflammatory Bowel Disease (ulcerative colitis [UC] and Crohn's disease) and relapsing multiple sclerosis. The objective of the open-label extension (OLE) of the TOUCHSTONE trial is to evaluate the long-term efficacy and safety of daily 1 mg ozanimod in patients with moderate to severe UC who had initially participated in the TOUCHSTONE trial. Methods: A total of 197 patients were randomized (1:1:1) and treated with daily ozanimod at 0.5 mg, 1mg (n=67), or placebo in the TOUCHSTONE trial. Of the initial 197 patients randomized, 170 (86%) entered the OLE and received daily 1 mg ozanimod, 131 (77%) completed the Week 44 assessments, and 109 (64%) remained in the OLE as of the data cut-off (March 2016). At the data cut-off, all remaining patients had received treatment in the OLE for ≥ 1 year. Results: At entry into the OLE, the partial Mayo Score (pMS) for patients on placebo, ozanimod 0.5 mg, and 1.0 mg was 4.6, 4.5, and 3.3 respectively. The pMS had improved in all groups (1.7, 1.7, and 1.9) at Week 44. The greatest improvement was reported in patients who received placebo or ozanimod 0.5 mg in the TOUCHSTONE trial with a change in pMS at Week 44 of -2.6, -2.7 and -1.3 in the placebo, 0.5 mg and 1 mg groups. Improvement occurred rapidly, in the first 4 to 8 weeks of the OLE with a change in pMS at Week 4 of -1.8, -1.5 and -0.8 and a change in pMS at Week 8 of -2.4, -1.9 and -1.1 in the placebo, 0.5 mg and 1 mg groups. At the Week 44 visit in the OLE, 119/131 (90.9%) had little or no active disease based on the physician global assessment (PGA 0 or 1), 129/131 (98.4%) had little or no blood in their stools (rectal bleeding subscore [RBS] 0 or 1), 111/131 (84.7%) had no blood in the stools (RBS 0). The most common adverse events (AEs) (>2.0%) during OLE were UC flare, anemia, upper respiratory tract infection, nasal pharyngitis, back pain, arthralgia, headache, alanine aminotransferase (ALT) or aspartate aminotransferase (AST) elevation. The only serious AEs in ≥2 patients were anemia, and ulcerative colitis flare. ALT and AST > 3x upper limit of normal occurred in 4 (2.4%) of the 170 patients in the OLE. All elevations were asymptomatic, < 5xULN, transient, and resolving while receiving continued treatment. Conclusion: Long-term treatment with ozanimod continues to be safe and well tolerated with good compliance and evidence of durable efficacy.

Effects of High- and Low-Fat Meals on the Pharmacokinetics of Ozanimod, a Novel Sphingosine 1-Phosphate Receptor Modulator

Introduction: Ozanimod (RPC1063) is an oral, selective sphingosine 1-phosphate (S1P) 1 and 5 receptor modulator in clinical development for the treatment of relapsing multiple sclerosis and inflammatory bowel disease. Since food has the potential to significantly influence the rate and extent of drug absorption, we designed and conducted a food-effect study with ozanimod. Methods: The objective of this study was to characterize the effects of high-fat and low-fat meals on the pharmacokinetics (PK) of a single oral dose of ozanimod in healthy adult subjects. This was a randomized, open-label, 3-period, 6-sequence, crossover study. Twenty-four healthy adult subjects were enrolled to receive a single 1-mg oral dose of ozanimod under 3 different conditions separated by washout periods of 7 days: fasted (treatment A), with a standard FDA high-fat meal (treatment B), and with a low-fat meal (treatment C). PK parameters for ozanimod and its two active metabolites (RP101988 [major] and RP101075 [minor]) were calculated. Point estimates and 90% confidence intervals (CIs) about the geometric mean ratio between treatments for maximum concentration (Cmax) and overall exposure (AUC0-inf or AUC0-last) were determined using linear mixed-effects models. Results: Twenty subjects completed both treatments A and B and 23 subjects completed both treatments A and C and provided PK data for the pair-wise comparison of fed vs fasted. The 90% CIs between fed (high-fat or low-fat) and fasted treatments for the Cmax and AUC0-inf of ozanimod and RP101988 were all within the no-effect boundary of 0.80 to 1.25. For the minor metabolite RP101075, the 90% CIs between high-fat and fasted for AUC0-last and the 90% CIs between low-fat and fasted for Cmax and AUC0-last were within the no-effect boundary. While the 90% CI between high-fat and fasted treatments for RP101075 Cmax (0.76 to 0.88) fell outside the lower bound of the no-effect boundary, this decrease was not considered to be clinically meaningful. Median time to reach Cmax (Tmax) for ozanimod was delayed following a high-fat meal (12 hours) compared to fasted and lowfat meal conditions (8 hours), but the range (6 to 12 hours) was the same. Mean elimination half-life (t1/2) values for ozanimod and its active metabolites ranged from 17-21 hours and were similar across all 3 treatments. Overall, single oral doses of 1 mg ozanimod were considered generally well tolerated. Conclusion: Ozanimod may be taken with or without food.

Sphingosine-1-Phosphate (S1P) and S1P Signaling Pathway: Therapeutic Targets in Autoimmunity and Inflammation.

Sphingosine-1-phosphate (S1P) and S1P receptors (S1PR) are ubiquitously expressed. S1P-S1PR signaling has been well characterized in immune trafficking and activation in innate and adaptive immune systems. However, the full extent of its involvement in the pathogenesis of autoimmune diseases is not well understood. FTY720 (fingolimod), a non-selective S1PR modulator, significantly decreased annualized relapse rates in relapsing-remitting multiple sclerosis (MS). FTY720, which primarily targets S1P receptor 1 asafunctional antagonist, arrests lymphocyte egress from secondary lymphoid tissues and reduces neuroinflammation in the central nervous system (CNS). Recent studies suggest that FTY720 also decreases astrogliosis and promotes oligodendrocyte differentiation within the CNS and may have therapeutic benefit to prevent brain atrophy. Since S1P signaling is involved in multiple immune functions, therapies targeting S1P axis may be applicable to treat autoimmune diseases other than MS. Currently, over a dozen selective S1PR and S1P pathway modulators with potentially superior therapeutic efficacy and better side-effect profiles are in the pipeline of drug development. Furthermore, newly characterized molecules such as apolipoprotein M (ApoM) (S1P chaperon) and SPNS2 (S1P transporter) are also potential targets for treatment of autoimmune diseases. Finally, the application of therapies targeting S1P and S1P signaling pathways may be expanded to treat several other immune-mediated disorders (such as post-infectious diseases, post-stroke and post-stroke dementia) and inflammatory conditions beyond their application in primary autoimmune diseases.

Safety and efficacy of the selective sphingosine 1-phosphate receptor modulator ozanimod in relapsing multiple sclerosis (RADIANCE): a randomised, placebo-controlled, phase 2 trial

Modulation of sphingosine 1-phosphate (S1P) receptors in a non-selective manner decreases disease activity in patients with multiple sclerosis but has potential safety concerns. We assessed the safety and efficacy of the oral selective S1P receptor modulator ozanimod in patients with relapsing multiple sclerosis. RADIANCE is a combined phase 2/3 trial. Patients with relapsing multiple sclerosis were recruited from 55 academic and private multiple sclerosis clinics in 13 countries across Europe and the USA. Eligible participants were aged 18-55 years, had an Expanded Disability Status Scale (EDSS) score of 0-5·0, and had either one or more relapses in the previous 12 months, or one or more relapses in the past 24 months and one or more gadolinium-enhancing lesions on MRI in the previous 12 months before screening. Participants were assigned by a computer-generated randomisation sequence in a 1:1:1 ratio to ozanimod (0·5 mg or 1 mg) or matching placebo once daily for 24 weeks by an independent, unmasked, statistical team. Trial participants, study site personnel, MRI assessors, steering committee members, and the study statistician were masked to treatment assignment. To attenuate first-dose cardiac effects, ozanimod was up-titrated from 0·25 mg to 0·5 mg or 1 mg over 8 days. The primary endpoint was the cumulative number of total gadolinium-enhancing MRI lesions measured by an independent MRI analysis centre at weeks 12-24 after treatment initiation. Analysis was by intention to treat. Here, we report results from the 24-week phase 2 trial. This trial is registered with ClinicalTrials.gov, number NCT01628393. The 2-year phase 3 trial is ongoing. The first patient was randomised on Oct 18, 2012, and the final visit of the last randomised patient was on May 11, 2014. The intention-to-treat and safety population consisted of 258 participants, 88 were assigned placebo, 87 ozanimod 0·5 mg, and 83 ozanimod 1 mg; 252 (98%) patients completed the assigned treatment. The mean cumulative number of gadolinium-enhancing lesions at weeks 12-24 was 11·1 (SD 29·9) with placebo compared with 1·5 (3·7) with ozanimod 0·5 mg (odds ratio 0·16, 95% CI 0·08-0·30; p<0·0001) and 1·5 (3·4) with ozanimod 1 mg (odds ratio 0·11, 95% CI 0·06-0·21; p<0·0001). Three serious adverse events unrelated to treatment were reported in patients assigned ozanimod 0·5 mg: optic neuritis, somatoform autonomic dysfunction, and cervical squamous metaplasia (HPV-related). No serious infectious or cardiac adverse events were reported, and no cases of macular oedema arose. The most common adverse events in the ozanimod 0·5 mg and 1 mg groups compared with placebo were nasopharyngitis (11 and five vs 12), headache (five and three vs eight), and urinary-tract infections (six and two vs two). The maximum reduction in mean heart rate by Holter monitoring during the first 6 h in ozanimod-treated participants was less than 2 beats per min (bpm) compared with baseline, with no patient having a minimum hourly heart rate less than 45 bpm. Electrocardiograms and 24-h Holter monitoring showed no increased incidence of atrioventricular block or sinus pause with ozanimod. Ozanimod significantly reduced MRI lesion activity in participants with relapsing multiple sclerosis, with a favourable safety profile over a period of 24 weeks. These findings warrant phase 3 trials, which are ongoing. Receptos, Inc.

Therapeutic Potential of the Modulation of Sphingosine-1-Phosphate Receptors.

It is accepted that sphingolipids (SL) are not only structural lipids in cellular membranes, but also key regulators of different cell process. Sphingosine-1-phosphate (S1P) is a member of this family involved, inter alia, in cell migration, angiogenesis and cell proliferation processes, being able to play different intracellular and extracellular roles. When S1P is transported out of the cell, it binds S1P specific G protein-coupled receptors, which are mainly involved in the regulation of the immune, vascular and nervous systems. These effects account for the vast diversity of functions that arise from the activation of S1P receptors. Deregulation of S1P levels is correlated with several pathologies, such as autoimmune disorders and cancer. Consequently, the correct modulation of these receptors represents a valuable approach for the development of new therapeutic strategies. Along this line, the non-selective S1P receptor agonist fingolimod (FTY720) has been commercialized recently for the treatment of multiple sclerosis and several related S1P receptor modulators are ongoing clinical trials. However, despite the progress in this field, the biological functions of S1P receptors are not still well elucidated. For this reason, several studies are being developed in order to better understand the functions of these receptors, making use of new selective S1P receptor agonists and antagonists as pharmacological tools.

Sphingosine-1-Phosphate/Sphingosine-1-Phosphate Receptor 2 Axis Can Promote Mouse and Human Primary Mast Cell Angiogenic Potential through Upregulation of Vascular Endothelial Growth Factor-A and Matrix Metalloproteinase-2.

Mast cells (MC) are present in most vascularized tissues around the vasculature likely exerting immunomodulatory functions. Endowed with diverse mediators, resident MC represent first-line fine-tuners of local microenvironment. Sphingosine-1-phosphate (S1P) functions as a pluripotent signaling sphingolipid metabolite in health and disease. S1P formation occurs at low levels in resting MC and is upregulated upon activation. Its export can result in type 2 S1P receptor- (S1PR2-) mediated stimulation of MC, further fueling inflammation. However, the role of S1PR2 ligation in proangiogenic vascular endothelial growth factor- (VEGF-) A and matrix metalloproteinase- (MMP-) 2 release from MC is unknown. Using a preclinical MC-dependent model of acute allergic responses and in vitro stimulated primary mouse bone marrow-derived MC (BMMC) or human primary skin MC, we report that S1P signaling resulted in substantial amount of VEGF-A release. Similar experiments using S1pr2-deficient mice or BMMC or selective S1P receptor agonists or antagonists demonstrated that S1P/S1PR2 ligation on MC is important for VEGF-A secretion. Further, we show that S1P stimulation triggered transcriptional upregulation of VEGF-A and MMP-2 mRNA in human but not in mouse MC. S1P exposure also triggered MMP-2 secretion from human MC. These studies identify a novel proangiogenic axis encompassing MC/S1P/S1PR2 likely relevant to inflammation.

A Randomized, Double-Blind, Placebo-Controlled Trial of Ozanimod, an Oral S1P Receptor Modulator, in Moderate to Severe Ulcerative Colitis: Results of the Maintenance Period of the TOUCHSTONE Study

Introduction: Ozanimod (RPC1063) is an oral, selective sphingosine 1-phosphate (S1P) 1 and 5 receptor modulator in clinical development for the treatment of ulcerative colitis (UC) and relapsing multiple sclerosis. The objective of the maintenance period of TOUCHSTONE was to evaluate the longer term efficacy and safety of 0.5 mg (low dose, LD) and 1 mg (high dose, HD) ozanimod in comparison to placebo (PBO), in patients with moderate to severe UC. Methods: This randomized, double-blind, placebo-controlled trial assessed the efficacy, safety and tolerability of two orally administered doses of ozanimod vs placebo in patients with moderate to severe UC. A total of 197 patients were randomized (1:1:1) and treated once daily with HD (n=67), LD (n=65) or PBO (n=65). As previously reported, a significantly greater proportion of patients receiving HD were in clinical remission, clinical response, and had mucosal improvement than placebo patients at week 8. Patients who achieved clinical response at week 8 continued into the maintenance period (MP) with their original treatment for an additional 24 weeks. Results: Of 197 patients in the induction period, 103 (52.3%) entered the MP and 91 (88.3%) completed. At Week 32 clinical remission occurred in 14/67 (20.9%), HD (p=0.0108 vs. PBO), 17/65 (26.2%), LD (p=0.0021), and 4/65 (6.2%), PBO; clinical response occurred in 34/67 (50.7%), HD (p=0.0002), 23/65 (35.4%), LD (p=0.0571), and 13/65 (20.0%), PBO; mucosal improvement (Mayo endo-subscore ≤1) occurred in 22/67 (32.8%) for HD (p=0.0046), 21/65 (32.3%), LD (p=0.0064), and 8/65 (12.3%), PBO. The improvement in total Mayo score at Week 32 from baseline was 3.4, HD (p=0.0004), 2.2, LD (p=0.1932), and 1.6, PBO. During the MP, adverse events (AEs) were most common in PBO. AEs occurred in 11/42 (26.2%), HD; 4/36 (11.1%), LD; 8/25 (32.0%), PBO. The most common AEs were: worsening of UC (HD, n=1; LD, 0; PBO, n=2) and UTI (HD, 0; LD, n=1; PBO, n=1). No AEs of special interest (cardiac, pulmonary, ophthalmologic, hepatic, malignancy or serious infections) were reported during the MP. Conclusion: Patients with moderate to severe UC who continued treatment with ozanimod were more likely to achieve and maintain clinical remission, clinical response and mucosal improvement than those receiving placebo. These data support the longer term efficacy and safety/tolerability profile of ozanimod in the treatment of moderate to severe UC.

Sphingosine 1-phosphate receptor modulators in multiple sclerosis.

Sphingosine 1-phosphate (S1P) receptor modulators possess a unique mechanism of action as disease-modifying therapy for multiple sclerosis (MS). Subtype 1 S1P receptors are expressed on the surfaces of lymphocytes and are important in regulating egression from lymph nodes. The S1P receptor modulators indirectly antagonize the receptor's function and sequester lymphocytes in lymph nodes. Fingolimod was the first S1P agent approved in the USA in 2010 for relapsing MS after two phase III trials (FREEDOMS and TRANSFORMS) demonstrated potent efficacy, and good safety and tolerability. Post-marketing experience, as well as a third phase III trial (FREEDOMS II), also showed favorable results. More selective S1P receptor agents-ponesimod (ACT128800), siponimod (BAF312), ozanimod (RPC1063), ceralifimod (ONO-4641), GSK2018682, and MT-1303-are still in relatively early stages of development, but phase I and II trials showed promising efficacy and safety. However, these observations have yet to be reproduced in phase III clinical trials.

Pharmacokinetics and disposition of CS-0777, a sphingosine 1-phosphate receptor modulator, in rats and monkeys

1. Disposition and metabolism of CS-0777 (1-{5-[(3R)-3-amino-4-hydroxy-3- methylbutyl]-1-methyl-1H-pyrrol-2-yl}-4-(4-methylphenyl) butan-1-one), a selective sphingosine 1-phosphate receptor-1 modulator under development for autoimmune conditions was investigated following oral and/or i.v. bolus administration to rats and monkeys.2. After oral administration of [14C]CS-0777, CS-0777 was well absorbed in rats and monkeys with total recoveries of over 90% of the dose, majorly in feces. CS-0777 and phosphorylated pharmacologically active metabolite of CS-0777 (M1) were highly bound to plasma proteins among rats, monkeys and humans (>93%).3. The structures of 12 metabolites were identified and phosphorylation and two hydroxylation pathways were proposed as primary metabolism. In the blood of rats and monkeys, the major metabolite was M1 and a few phosphorylated metabolites were also detected. Meanwhile, in urine and feces of rats and monkeys, not phosphorylated, but oxidized CS-0777 metabolites and/or those various conjugated metabolites were observed. This suggests that CS-0777 and its oxidized metabolites would be phosphorylated in the body, but their phosphorylated metabolites would revert back to their dephosphorylated form again then be further metabolized and finally eliminated from the body.4. Pharmacokinetic analysis using a reversible metabolism model revealed that the clearance of phosphorylation was larger than the clearance of dephosphorylation and elimination.

Effect of ceralifimod (ONO‐4641) on lymphocytes and cardiac function: Randomized, double‐blind, placebo‐controlled trial with an open‐label fingolimod arm

This randomized, double-blind, placebo-controlled, 6-arm, parallel-design study investigated cardiac and hematological pharmacodynamic effects of ceralifimod (ONO-4641), a selective sphingosine-1-phosphate (S1P) receptor modulator, over a broad dose range in direct comparison with the nonselective S1P modulator fingolimod. Healthy subjects were assigned to ceralifimod (0.01, 0.025, 0.05, or 0.10 mg), fingolimod (0.5 mg), or placebo once daily for 14 days (n = 24 per group). After 14 days of treatment, mean absolute lymphocyte count percentage change from baseline was greatest in the fingolimod (-62%) and ceralifimod 0.10 mg (-56%) groups. On treatment cessation, lymphocyte recovery was faster in the ceralifimod versus the fingolimod group. Ceralifimod showed dose- and concentration-dependent chronotropic effect. Cardiac effects in the fingolimod group were dependent on fingolimod-P concentrations. Maximum mean heart rate (HR) effect on day 1 was larger with fingolimod (placebo-adjusted change from time-matched baseline HR [ΔΔHR], -14.9 beats per minute [bpm]) versus ceralifimod (ΔΔHR, -6.2 and -12.0 bpm for the 0.05- and 0.10-mg doses, respectively). Ceralifimod's effect on the PR interval was minor. Safety biomarker results suggest that potential therapeutic doses of ceralifimod, in particular the 0.05-mg dose, might result in reduced occurrence of bradycardia, atrioventricular block absolute lymphocyte count and grade 3/4 lymphopenia compared with fingolimod 0.5 mg.

Sphingosin-1-phosphate Receptor 1: a Potential Target to Inhibit Neuroinflammation and Restore the Sphingosin-1-phosphate Metabolism.

Recent evidence suggests that an extreme shift may occur in sphingosine metabolism in neuroinflammatory contexts. Sphingosine 1-phosphate (S1P)-metabolizing enzymes (SMEs) regulate the level of S1P. We recently found that FTY720, a S1P analogue, and SEW2871, a selective S1P receptor 1 (S1P1) agonist, provide protection against neural damage and memory deficit in amyloid beta (Aβ)-injected animals. This study aimed to evaluate the effects of these two analogues on the expression of SMEs as well as their anti-inflammatory roles. Rats were treated with intracerebral lipopolysaccharide (LPS) or Aβ. Memory impairment was assessed by Morris water maze and the effects of drugs on SMEs as well as inflammatory markers, TNF- α and COX-II, were determined by immunoblotting. Aβ and LPS differentially altered the expression profile of SMEs. In Aβ-injected animals, FTY720 and SEW2871 treatments exerted anti-inflammatory effects and restored the expression profile of SMEs, in parallel to our previous findings. In LPS animals however, in spite of anti-inflammatory effects of the two analogues, only FTY720 restored the levels of SMEs and prevented memory deficit. The observed ameliorating effects of FTY720 and SEW7821 can be partly attributed to the interruption of the vicious cycle of abnormal S1P metabolism and neuro-inflammation. The close imitation of the FTY720 effects by SW2871 in Aβ-induced neuro-inflammation may highlight the attractive role of S1P1 as a potential target to restore S1P metabolism and inhibit inflammatory processes.

Pharmacophore-based design of novel oxadiazoles as selective sphingosine-1-phosphate (S1P) receptor agonists with in vivo efficacy.

Sphingosine-1-phosphate (S1P) receptor agonists have shown promise as therapeutic agents for multiple sclerosis (MS) due to their regulatory roles within the immune, central nervous system, and cardiovascular system. Here, the design and optimization of novel [1,2,4]oxadiazole derivatives as selective S1P receptor agonists are described. The structure-activity relationship exploration was carried out on the three dominant segments of the series: modification of the polar head group (P), replacement of the oxadiazole linker (L) with different five-membered heterocycles, and the use of diverse 2,2'-disubstituted biphenyl moieties as the hydrophobic tail (H). All three segments have a significant impact on potency, S1P receptor subtype selectivity, physicochemical properties, and in vitro absorption, distribution, metabolism, excretion and toxicity (ADMET) profile of the compounds. From these optimization studies, a selective S1P1 agonist, N-methyl-N-(4-{5-[2-methyl-2'-(trifluoromethyl)biphenyl-4-yl]-1,2,4-oxadiazol-3-yl}benzyl)glycine (45), and a dual S1P1,5 agonist, N-methyl-N-(3-{5-[2'-methyl-2-(trifluoromethyl)biphenyl-4-yl]-1,2,4-oxadiazol-3-yl}benzyl)glycine (49), emerged as frontrunners. These compounds distribute predominantly in lymph nodes and brain over plasma and induce long lasting decreases in lymphocyte count after oral administration. When evaluated head-to-head in an experimental autoimmune encephalomyelitis mouse model, together with the marketed drug fingolimod, a pan-S1P receptor agonist, S1P1,5 agonist 49 demonstrated comparable efficacy while S1P1 -selective agonist 45 was less potent. Compound 49 is not a prodrug, and its improved property profile should translate into a safer treatment of relapsing forms of MS.

P036 - Siponimod (BAF312) for the treatment of secondary progressive multiple sclerosis: Design of the phase 3 EXPAND trial

Background/objective Siponimod (BAF312), a next generation selective sphingosine 1-phosphate (S1P)-1 and -5 receptor modulator administered once-daily orally reduces lymphocyte infiltration into the CNS and may have direct CNS effects. Experimental studies indicate that siponimod readily crosses the blood–brain-barrier and may modulate neurobiological processes via S1P1 and S1P5 receptors on astrocytes and oligodendrocytes. In relapsing MS, S1P receptor modulation reduces accumulation of neurological impairment and slows progression of brain atrophy. These clinical and radiographic effects suggest that S1P receptor modulation might be effective in secondary progressive MS (SPMS). We present here the design of a phase 3 study intended to demonstrate the efficacy, safety and tolerability of siponimod compared to placebo in individuals with SPMS. Design/methods EXPAND (Exploring the efficacy and safety of siponimod in patients with secondary progressive multiple sclerosis) is a multicenter, randomized, double-blind, parallel-group, placebo-controlled variable treatment duration study (anticipated range 23–42 months). Approximately 1530 individuals, aged 18–60 years with SPMS (EDSS score of 3.0–6.5) will be randomized. Treatment will start with a 6-day dose titration (0.25, 0.25, 0.5, 0.75, 1.25, 2 mg) and continue at a dose of 2 mg or placebo (2:1). The primary objective of the study is to demonstrate the efficacy of siponimod relative to placebo in delaying the time to 3-month confirmed disability progression as measured by EDSS. The study has 90% power to detect a 30% reduction in the risk of 3-month confirmed disability progression (hazard ratio 0.70). Study will be stopped when 374 events (patients with progression) are observed. Results Details of study design will be presented at the congress. Conclusion New therapies, that are effective in delaying disability progression in patients with SPMS, are an important unmet medical need. The EXPAND study will explore the potential of siponimod in SPMS and help advance the knowledge of SPMS pathophysiology.

The S1P1 receptor-selective agonist CYM-5442 reduces the severity of acute GVHD by inhibiting macrophage recruitment.

FTY720, an agonist for four of the five known sphingosine-1-phosphate (S1P) receptors, has been reported to inhibit acute graft-versus-host disease (aGVHD). Because FTY720 functions through multiple S1P receptors, the mechanism of action through one or more of these receptors may account for its side effects. Thus, more selective S1P receptor modulators are needed to evaluate the roles of different S1P receptors and their therapeutic efficacies. In this study, we investigated the effect of an S1P1-selective agonist, CYM-5442, on the progression of aGVHD. We showed that CYM-5442 significantly inhibited but did not prevent aGVHD. CYM-5442 did not affect the infiltration of the donor T cells into the target organs, while the number of macrophages in GVHD organs was significantly reduced by CYM-5442 treatment. In vivo proliferation assays showed that the proliferation of macrophages was not suppressed by CYM-5442. Further studies using human endothelial cells demonstrated that CYM-5442 treatment downregulated CCL2 and CCL7 expression in endothelial cells, therefore reducing the migration of monocytes, from which tissue macrophages originate. Our data demonstrate the therapeutic efficacy of an S1P1-selective agonist in aGVHD and its possible mechanism of action. The results suggest that further investigations are needed regarding CYM-5442 as a potential therapeutic regimen for aGVHD.

Identification of a Metabolizing Enzyme in Human Kidney by Proteomic Correlation Profiling

Molecular identification of endogenous enzymes and biologically active substances from complex biological sources remains a challenging task, and although traditional biochemical purification is sometimes regarded as outdated, it remains one of the most powerful methodologies for this purpose. While biochemical purification usually requires large amounts of starting material and many separation steps, we developed an advanced method named “proteomic correlation profiling” in our previous study. In proteomic correlation profiling, we first fractionated biological material by column chromatography, and then calculated each protein's correlation coefficient between the enzyme activity profile and protein abundance profile determined by proteomics technology toward fractions. Thereafter, we could choose possible candidates for the enzyme among proteins with a high correlation value by domain predictions using informatics tools. Ultimately, this streamlined procedure requires fewer purification steps and reduces starting materials dramatically due to low required purity compared with conventional approaches. To demonstrate the generality of this approach, we have now applied an improved workflow of proteomic correlation profiling to a drug metabolizing enzyme and successfully identified alkaline phosphatase, tissue-nonspecific isozyme (ALPL) as a phosphatase of CS-0777 phosphate (CS-0777-P), a selective sphingosine 1-phosphate receptor 1 modulator with potential benefits in the treatment of autoimmune diseases including multiple sclerosis, from human kidney extract. We identified ALPL as a candidate protein only by the 200-fold purification and only from 1 g of human kidney. The identification of ALPL as CS-0777-P phosphatase was strongly supported by a recombinant protein, and contribution of the enzyme in human kidney extract was validated by immunodepletion and a specific inhibitor. This approach can be applied to any kind of enzyme class and biologically active substance; therefore, we believe that we have provided a fast and practical option by combination of traditional biochemistry and state-of-the-art proteomic technology.

KRP-203, Sphingosine 1-Phosphate Receptor Type 1 Agonist, Ameliorates Atherosclerosis in LDL-R −/− Mice

Sphingosine 1-phosphate (S1P) partly accounts for antiatherogenic properties of high-density lipoproteins. We previously demonstrated that FTY720, a synthetic S1P analog targeting all S1P receptors but S1P receptor type 2, inhibits murine atherosclerosis. Here, we addressed the identity of S1P receptor mediating atheroprotective effects of S1P. Low-density lipoprotein receptor-deficient mice on cholesterol-rich diet were given selective S1P receptor type 1 agonist KRP-203 (3.0 mg/kg per day; 6 and 16 weeks). KRP-203 substantially reduced atherosclerotic lesion formation without affecting plasma lipid concentrations. However, KRP-203 induced lymphopenia, reduced total (CD4(+), CD8(+)) and activated (CD69(+)/CD8(+), CD69(+)/CD4(+)) T cells in peripheral lymphoid organs, and interfered with lymphocyte function, as evidenced by decreased T-cell proliferation and interleukin-2 and interferon-γ production in activated splenocytes. Cyto- and chemokine (tumor necrosis factor-α, regulated and normal T cell expressed and secreted) levels in plasma and aortas were reduced by KRP-203 administration. Moreover, macrophages from KRP-203-treated mice showed reduced expression of activation marker MCH-II and poly(I:C)-elicited production of tumor necrosis factor-α, monocyte chemoattractant protein-1, and interleukin-6. In vitro studies demonstrated that KRP-203 reduced tumor necrosis factor-α, interleukin-6, and interferon-γ-induced protein-10 production; IκB and signal transducer and activator of transcription-1 phosphorylation; and nuclear factor κB and signal transducer and activator of transcription-1 activation in poly(I:C)-, lipopolysaccharide-, or interferon-γ-stimulated bone marrow macrophages, respectively. Present results demonstrate that activation of S1P signaling pathways inhibit atherosclerosis by modulating lymphocyte and macrophage function and suggest that S1P receptor type 1 at least partially mediates antiatherogenic effects of S1P.

An Exploratory Analysis of Magnetic Resonance Imaging Outcomes in the DreaMS Trial: A Double-Blind, Placebo-Controlled, Phase 2, 26-Week Trial of a Selective Sphingosine 1-Phosphate Receptor Agonist ONO-4641 in Patients with Relapsing–Remitting Multiple Sclerosis (S31.005)

An Exploratory Analysis of Magnetic Resonance Imaging Outcomes in the DreaMS Trial: A Double-Blind, Placebo-Controlled, Phase 2, 26-Week Trial of a Selective Sphingosine 1-Phosphate Receptor Agonist ONO-4641 in Patients with Relapsing–Remitting Multiple Sclerosis (S31.005)

Proximal tubule sphingosine kinase-1 has a critical role in A1 adenosine receptor-mediated renal protection from ischemia

Renal ischemia reperfusion injury is a major cause of acute kidney injury. We previously found that renal A1 adenosine receptor (A1AR) activation attenuated multiple cell death pathways including necrosis, apoptosis and inflammation. Here, we tested whether induction of cytoprotective sphingosine kinase (SK)-1 and sphingosine-1 phosphate (S1P) synthesis might be the mechanism of protection. A selective A1AR agonist (CCPA) increased the synthesis of S1P and selectively induced SK-1 in mouse kidney and HK-2 cells. This agonist failed to protect SK1-knockout but protected SK2-knockout mice against renal ischemia reperfusion injury indicating a critical role of SK1 in A1AR-mediated renal protection. Inhibition of SK prevented A1AR-mediated defense against necrosis and apoptosis in HK-2 cells. A selective S1P1R antagonist (W146) and global in vivo gene knockdown of S1P1Rs with small interfering RNA completely abolished the renal protection provided by CCPA. Mice selectively deficient in renal proximal tubule S1P1Rs (S1P1Rflox/flox PEPCKCre/−) were not protected against renal ischemia reperfusion injury by CCPA. Mechanistically, CCPA increased nuclear translocation of hypoxia inducible factor-1α in HK-2 cells and selective hypoxia inducible factor-1α inhibition blocked A1AR-mediated induction of SK1. Thus, proximal tubule SK-1 has a critical role in A1AR-mediated protection against renal ischemia reperfusion injury.

Pharmacological Modulation of Peripheral T and B Lymphocytes by a Selective Sphingosine 1‐Phosphate Receptor‐1 Modulator

CS-0777 is a selective sphingosine 1-phosphate receptor-1 (S1P(1)) modulator under development for treatment of autoimmune conditions. A randomized, double-blind, placebo-controlled study was conducted to assess the safety, tolerability, pharmacokinetics, and pharmacodynamics of single oral doses of CS-0777 in escalating dose cohorts of healthy male participants (0.1, 0.3, 1.0, and 2.5 mg; 6 active, 2 placebo per cohort). Primary pharmacodynamic parameters were absolute lymphocyte counts and lymphocyte subsets (CD4 and CD8 T and B cells). CS-0777 resulted in a pronounced, dose-dependent decrease in absolute lymphocyte counts (mean percent decrease from baseline at 24 hours postdose: 7%, 26%, 52%, 79%, and 85%, for placebo and 0.1, 0.3, 1.0, and 2.5 mg, respectively). Dose-related decreases of similar magnitude were observed for T and B cell subsets. Mean total white blood cell and neutrophil counts remained within normal ranges for all dose levels. CS-0777 was well tolerated, and there were no serious or severe adverse events. Mild, asymptomatic bradycardia and transaminase elevations (<3-fold upper limit of normal), similar to findings for other S1P receptor modulators, were observed at the highest dose level (2.5 mg). Therefore, CS-0777 shows potent activity in humans and may hold potential for treatment of autoimmune conditions such as multiple sclerosis.

Sphingosine-1-Phosphate-Induced Airway Hyper-Reactivity in Rodents Is Mediated by the Sphingosine-1-Phosphate Type 3 Receptor

There is a need to better understand the mechanism of airway hyper-reactivity, a key feature of asthma. Evidence suggests that sphingosine-1-phosphate (S1P) could be a major player in this phenomenon. The purpose of this work was to define the S1P receptor responsible for this phenomenon. We have studied, in the rat, the effect of two S1P synthetic receptor ligands, 2-amino-2-[2-(4-octylphenyl)ethyl]propane-1,3-diol (FTY720) (which in its phosphorylated form is a potent agonist at each S1P receptor except S1P(2)) and 3-[[2-[4-phenyl-3-(trifluoromethyl)phenyl]-1-benzothiophen-5-yl]methylamino]propanoic acid (AUY954) (a selective S1P(1) agonist) on lung function in vivo. This was complemented by in vitro studies using isolated trachea from the rat, the S1P(3) receptor-deficient mouse, and its wild-type counterpart. After oral administration, FTY720 induced a generalized airway hyper-reactivity to a range of contractile stimuli. This was observed as early as 1 h postdosing, lasted for at least 24 h, and was not subject to desensitization. In both rat and wild-type mouse isolated trachea, preincubation with the active phosphorylated metabolite of FTY720 induced hyper-responsiveness to 5-hydroxytryptamine. This effect was not seen in the isolated tracheas from S1P(3) receptor-deficient mice. AUY954, did not mimic the effect of FTY720 either in vivo or in vitro. Our data are consistent with activation of the S1P pathway inducing a generalized airway hyper-reactivity in rats and mice that is mediated by the S1P(3) receptor. S1P(3) receptor antagonists might prove to be useful as new therapeutic strategies aimed at blocking the airway hyper-reactivity observed in asthma.