SKI-349, a Sphingosine Kinases 1/2 Inhibitor, Suppresses Cell Viability, Invasion, and AKT/mTOR Signaling Pathway, and Shows Synergistic Cytotoxic Effects with Sorafenib in Hepatocellular Carcinoma

SKI-349 is a novel sphingosine kinases (SPHK) inhibitor with anti-tumor effects. This study aimed to assess the effect of SKI-349 on cell biological behaviors, downstream pathways, and its synergistic effect with sorafenib in hepatocellular carcinoma (HCC). HCC cell lines (Huh7 and Hep3B) were treated with SKI-349 at concentrations of 1, 2, 4, or 8 μM. Then, SPHK1/2 activity, cell viability, proliferation, apoptosis, invasion, and protein expressions of phosphorylated-protein kinase B (p-AKT), AKT, phosphorylated-mammalian target of rapamycin (p-mTOR) and mTOR were detected. Combination index values of SKI-349 (0, 1, 2, 4, or 8 μM) and sorafenib (0, 2.5, 5, 10, or 20 μM) were calculated. SKI-349 decreased the relative SPHK1 and SPHK2 activity compared with blank control in a dose-dependent manner in the Huh7 and Hep3B cell lines. Meanwhile, SKI-349 reduced cell viability, 5-ethynyl-2'-deoxyuridine (EdU) positive cells, and invasive cells, while it increased apoptotic cells compared to blank control in a dose-dependent manner in Huh7 and Hep3B cell lines. Based on the western blot assay, SKI-349 decreased the ratio of p-AKT to AKT and that of p-mTOR to mTOR compared with blank control in a dose-dependent manner in the Huh7 and Hep3B cell lines. Additionally, SKI-349 combined with sorafenib declined cell viability with concentration gradient effects compared to SKI-349 sole treatment, and they had synergistic cytotoxic effects in Huh7 and Hep3B cell lines. SKI-349 suppresses SPHK1 and SPHK2 activity, cell viability, invasion, and AKT/mTOR signaling pathway, as well as exhibits a synergistic cytotoxic effect with sorafenib in HCC.

LASSO regression shows histidine and sphingosine 1 phosphate are linked to both sepsis mortality and endothelial damage

Sepsis is a major cause of death worldwide, with a mortality rate that has remained stubbornly high. The current gold standard of risk stratifying sepsis patients provides limited mechanistic insight for therapeutic targeting. An improved ability to predict sepsis mortality and to understand the risk factors would allow better treatment targeting. Sepsis causes metabolic dysregulation in patients; therefore, metabolomics offers a promising tool to study sepsis. It is also known that that in sepsis endothelial cells affecting their function regarding blood clotting and vascular permeability. We integrated metabolomics data from patients admitted to an intensive care unit for sepsis, with commonly collected clinical features of their cases and two measures of endothelial function relevant to blood vessel function, platelet endothelial cell adhesion molecule and soluble thrombomodulin concentrations in plasma. We used least absolute shrinkage and selection operator penalized regression, and pathway enrichment analysis to identify features most able to predict 30-day survival. The features important to sepsis survival include carnitines, and amino acids. Endothelial proteins in plasma also predict 30-day mortality and the levels of these proteins also correlate with a somewhat overlapping set of metabolites. Overall metabolic dysregulation, particularly in endothelial cells, may be a contributory factor to sepsis response. By exploring sepsis metabolomics data in conjunction with clinical features and endothelial proteins we have gained a better understanding of sepsis risk factors.

Blocking sphingosine 1-phosphate receptor 1 with modulators reduces immune cells infiltration and alleviates endometriosis in mice

RESEARCH QUESTION

Do sphingosine 1-phosphate (S1P) modulators have therapeutic effects on endometriosis in mice and, if they do, which receptor is responsible for these effects?

DESIGN

A surgically induced endometriosis mouse model was established. In the pilot experiment, lesions were harvested to assess fibrosis and inflammation and determine the optimal concentration of a broad-spectrum S1P modulator, FTY720. Subsequently, FTY720 was compared with a selective S1P receptor 1 modulator, SEW2871 to evaluate their effects on endometriotic lesion growth, fibrosis, inflammation and immune cell infiltration.

RESULTS

The results demonstrated that both FTY720 and SEW2871, two S1P receptor modulators, effectively inhibited the growth and fibrosis of endometriotic lesions. SEW2871 inhibited inflammation-related cytokine expression, including PTGS-2, IL-1β, TNF-α and TGF-β1, more effectively compared with FTY720. Lymphopaenia was mainly caused by FTY720, whereas SEW2871 had a lesser effect. Both FTY720 and SEW2871 significantly reduced CD45+ cells (P = 0.002 and P = 0.032, respectively) and F4/80+ cells (P < 0.001 and P = 0.004, respectively) infiltration into the lesions, with FTY720 exerting a strong regulatory effect on CD4+ T cells.

CONCLUSIONS

This study suggests that S1P receptor 1 could be investigated as a potential novel therapeutic target for endometriosis in the future.

A Preliminary Study of Pharmacokinetics and Pharmacodynamics of Oral Fingolimod in Dogs

BACKGROUND/AIM

Fingolimod is a sphingosine-1-phosphate receptor modulator that prevents lymphocytes egress from lymphoid organs. It has been used as a disease-modifying drug for human multiple sclerosis and has shown better therapeutic effects than other conventional therapies. Therefore, this study was performed to obtain preclinical data of fingolimod in dogs.

MATERIALS AND METHODS

Nine laboratory Beagle dogs were used and randomized into three groups for pharmacokinetics (PK) and pharmacodynamics (PD). The dogs were administered once with a low-dose (0.01 mg/kg, n=3), medium-dose (0.05 mg/kg, n=3), and high-dose (0.1 mg/kg, n=3) of fingolimod, orally. Samples were collected serially at predetermined time points, and whole blood fingolimod concentrations were measured using high-performance liquid chromatography-mass spectrometry. Differential counts of leukocytes over time were determined to identify immune cells' response to fingolimod.

RESULTS

Regarding PK, the concentration of fingolimod in the blood increased in a dose-dependent manner, but it was not proportional. Regarding PD, the number of lymphocytes significantly decreased compared to baseline in all dose groups (low-dose, p=0.0002; medium-dose, p<0.0001; high-dose, p=0.0012). Eosinophils were significantly reduced in low- (p=0.0006) and medium- (p=0.0006) doses, and neutrophils were also significantly reduced in medium-(p=0.0345) and high- (p=0.0016) doses.

CONCLUSION

This study provides the basis for future clinical applications of fingolimod in dogs with immune-mediated diseases, such as meningoencephalitis of unknown etiology.

The effect of Fingolimod on patients with moderate to severe COVID-19

Hyper-inflammation, cytokine storm, and recruitment of immune cells lead to uncontrollable endothelial cell damage in patients with coronavirus disease 2019 (COVID-19). Sphingosine 1-phosphate (S1P) signaling is needed for endothelial integrity and its decreased serum level is a predictor of clinical severity in COVID-19. In this clinical trial, the effect of Fingolimod, an agonist of S1P, was evaluated on patients with COVID-19. Forty patients with moderate to severe COVID-19 were enrolled and divided into two groups including (1) the control group (n = 21) receiving the national standard regimen for COVID-19 patients and (2) the intervention group (n = 19) that prescribed daily Fingolimod (0.5 mg) for 3 days besides receiving the standard national regimen for COVID-19. The hospitalization period, re-admission rate, intensive care unit (ICU) administration, need for mechanical ventilation, and mortality rate were assessed as primary outcomes in both groups. The results showed that re-admission was significantly decreased in COVID-19 patients who received Fingolimod compared to the controls (p = .04). In addition, the hemoglobin levels of the COVID-19 patients in the intervention group were increased compared to the controls (p = .018). However, no significant differences were found regarding the intubation or mortality rate between the groups (p > .05). Fingolimod could significantly reduce the re-admission rate after hospitalization with COVID-19. Fingolimod may not enhance patients' outcomes with moderate COVID-19. It is necessary to examine these findings in a larger cohort of patients with severe to critical COVID-19.

Unveiling the biological role of sphingosine-1-phosphate receptor modulators in inflammatory bowel diseases

Inflammatory bowel disease (IBD) is chronic inflammation of the gastrointestinal tract that has a high epidemiological prevalence worldwide. The increasing disease burden worldwide, lack of response to current biologic therapeutics, and treatment-related immunogenicity have led to major concerns regarding the clinical management of IBD patients and treatment efficacy. Understanding disease pathogenesis and disease-related molecular mechanisms is the most important goal in developing new and effective therapeutics. Sphingosine-1-phosphate (S1P) receptor (S1PR) modulators form a class of oral small molecule drugs currently in clinical development for IBD have shown promising effects on disease improvement. S1P is a sphingosine-derived phospholipid that acts by binding to its receptor S1PR and is involved in the regulation of several biological processes including cell survival, differentiation, migration, proliferation, immune response, and lymphocyte trafficking. T lymphocytes play an important role in regulating inflammatory responses. In inflamed IBD tissue, an imbalance between T helper (Th) and regulatory T lymphocytes and Th cytokine levels was found. The S1P/S1PR signaling axis and metabolism have been linked to inflammatory responses in IBD. S1P modulators targeting S1PRs and S1P metabolism have been developed and shown to regulate inflammatory responses by affecting lymphocyte trafficking, lymphocyte number, lymphocyte activity, cytokine production, and contributing to gut barrier function.

Tumor Derived Extracellular Vesicles Drive T Cell Exhaustion in Tumor Microenvironment through Sphingosine Mediated Signaling and Impacting Immunotherapy Outcomes in Ovarian Cancer

SPHK1 (sphingosine kinase-1) catalyzes the phosphorylation of sphingosine to sphingosine-1-phosphate (S1P), is found to be highly expressed in solid tumors. Here, extracellular vesicles (EVs) are identified as the key transporters of SPHK1 to the tumor microenvironment. Consequently, SPHK1-packaged EVs elevate S1P levels in the tumor microenvironment, where S1P appears as an immunosuppressive agent. However, the exact mechanism of how S1P mediates its immunosuppressive effects in cancer is not understood. It is investigated that S1P can induce T cell exhaustion. S1P can also upregulate programmed death ligand-1 (PDL-1) expression through E2F1-mediated transcription. Notably, an SPHK1 inhibitor PF543 improves T cell-mediated cytotoxicity. Furthermore, combining PF543 with an anti-PD-1 antibody reduces tumor burden and metastasis more effectively than PF543 alone in vivo. These data demonstrate a previously unrecognized mechanism of how SPHK1-packaged EVs contribute to the progression of ovarian cancer and thus present the potential clinical application of inhibiting SPHK1/S1P signaling to improve immune checkpoint blockage (anti-PD-1 antibody) therapy in ovarian cancer.

The Anti-Infectious Role of Sphingosine in Microbial Diseases

Sphingolipids are important structural membrane components and, together with cholesterol, are often organized in lipid rafts, where they act as signaling molecules in many cellular functions. They play crucial roles in regulating pathobiological processes, such as cancer, inflammation, and infectious diseases. The bioactive metabolites ceramide, sphingosine-1-phosphate, and sphingosine have been shown to be involved in the pathogenesis of several microbes. In contrast to ceramide, which often promotes bacterial and viral infections (for instance, by mediating adhesion and internalization), sphingosine, which is released from ceramide by the activity of ceramidases, kills many bacterial, viral, and fungal pathogens. In particular, sphingosine is an important natural component of the defense against bacterial pathogens in the respiratory tract. Pathologically reduced sphingosine levels in cystic fibrosis airway epithelial cells are normalized by inhalation of sphingosine, and coating plastic implants with sphingosine prevents bacterial infections. Pretreatment of cells with exogenous sphingosine also prevents the viral spike protein of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) from interacting with host cell receptors and inhibits the propagation of herpes simplex virus type 1 (HSV-1) in macrophages. Recent examinations reveal that the bactericidal effect of sphingosine might be due to bacterial membrane permeabilization and the subsequent death of the bacteria.

Sphingosine-1-Phosphate Attenuates Lipopolysaccharide-Induced Pericyte Loss via Activation of Rho-A and MRTF-A

The high mortality seen in sepsis is caused by a systemic hypotension in part owing to a drastic increase in vascular permeability accompanied by a loss of pericytes. As has been shown previously, pericyte retention in the perivascular niche during sepsis can enhance the integrity of the vasculature and promote survival via recruitment of adhesion proteins such as VE-cadherin and N-cadherin. Sphingosine-1-phosphate (S1P) represents a lipid mediator regulating the deposition of the crucial adhesion molecule VE-cadherin at sites of interendothelial adherens junctions and of N-cadherin at endothelial-pericyte adherens junctions. Furthermore, in septic patients, S1P plasma levels are decreased and correlate with mortality in an indirectly proportional way. In the present study, we investigated the potential of S1P to ameliorate a lipopolysaccharide-induced septic hypercirculation in mice. Here we establish S1P as an antagonist of pericyte loss, vascular hyperpermeability, and systemic hypotension, resulting in an increased survival in mice. During sepsis S1P preserved VE-cadherin and N-cadherin deposition, mediated by a reduction of Src and cadherin phosphorylation. At least in part, this effect is mediated by a reduction of globular actin and a subsequent increase in nuclear translocation of MRTF-A (myocardin-related transcription factor A). These findings indicate that S1P may counteract pericyte loss and microvessel disassembly during sepsis and additionally emphasize the importance of pericyte-endothelial interactions to stabilize the vasculature.

Sphingosine-1-phosphate activates the AKT pathway to inhibit chemotherapy induced human granulosa cell apoptosis

To investigate whether sphingosine-1-phosphate (S1P), an apoptosis-inhibitor would be able to inhibit chemotherapy induced human granulosa cell apoptosis. Cultures of primary granulosa cells were isolated from women undergoing in vitro fertilization (IVF). MTT assay was used to measure the optimum concentration of CTX and S1P acts on human granulosa cells. Granulosa cells were added with pertussis toxin (PTX), the PI3K inhibitor LY294002. Western blot analysis was used to analyze the signaling pathway of proteins and cell apoptosis. We found that S1P (10 mm) statistically significantly decreased granulosa cell apoptosis after cyclophosphamide (CTX) treatment. The decreased cell apoptosis induced by S1P was abolished after treatment with LY294002, PI3K inhibitor.

CONCLUSIONS

Treatment with S1P can inhibit the CTX-induced granulosa cell apoptosis. The S1P protective effect is mediated by activating the PI3K/Akt pathway.

Novel sphingosine kinase-1 inhibitor, LCL351, reduces immune responses in murine DSS-induced colitis

Sphingosine-1-phosphate (S1P) is a biologically active sphingolipid metabolite which has been implicated in many diseases including cancer and inflammatory diseases. Recently, sphingosine kinase 1 (SK1), one of the isozymes which generates S1P, has been implicated in the development and progression of inflammatory bowel disease (IBD). Based on our previous work, we set out to determine the efficacy of a novel SK1 selective inhibitor, LCL351, in a murine model of IBD. LCL351 selectively inhibits SK1 both in vitro and in cells. LCL351, which accumulates in relevant tissues such as colon, did not have any adverse side effects in vivo. In mice challenged with dextran sodium sulfate (DSS), a murine model for IBD, LCL351 treatment protected from blood loss and splenomegaly. Additionally, LCL351 treatment reduced the expression of pro-inflammatory markers, and reduced neutrophil infiltration in colon tissue. Our results suggest inflammation associated with IBD can be targeted pharmacologically through the inhibition and degradation of SK1. Furthermore, our data also identifies desirable properties of SK1 inhibitors.

New Immunosuppressive Sphingoid Base and Ceramide Analogues in Wild Cordyceps

A comprehensive identification of sphingoid bases and ceramides in wild Cordyceps was performed by integrating a sequential chromatographic enrichment procedure and an UHPLC-ultrahigh definition-Q-TOF-MS based sphingolipidomic approach. A total of 43 sphingoid bases and 303 ceramides were identified from wild Cordyceps, including 12 new sphingoid base analogues and 159 new ceramide analogues based on high-resolution MS and MS/MS data, isotope distribution, matching with the comprehensive personal sphingolipid database, confirmation by sphingolipid standards and chromatographic retention time rule. The immunosuppressive bioassay results demonstrated that Cordyceps sphingoid base fraction exhibits more potent immunosuppressive activity than ceramide fraction, elucidating the immunosuppressive ingredients of wild Cordyceps. This study represented the most comprehensive identification of sphingoid bases and ceramides from a natural source. The findings of this study provided an insight into therapeutic application of wild Cordyceps.

Lack of Sphingosine Causes Susceptibility to Pulmonary Staphylococcus Aureus Infections in Cystic Fibrosis

BACKGROUND

Pulmonary Staphylococcus aureus (S. aureus) infections occur early in a high percentage of cystic fibrosis (CF) patients and it is believed that these infections facilitate further colonization of CF lungs with Pseudomonas aeruginosa (P. aeruginosa). Previous studies demonstrated a marked reduction of sphingosine in tracheal and bronchial epithelial cells in CF compared to wild type mice, while ceramide is massively increased in CF mice.

METHODS

We investigated the effect of C18-sphingosine and C16-ceramide on S. aureus in vitro. Based on our results we performed pulmonary infections with S. aureus and tested the influence of sphingosine inhalation.

RESULTS

In vitro incubation of S. aureus with C18-sphingosine rapidly killed S. aureus, while C16-ceramide did not affect bacterial survival, but abrogated the effect of C18-sphingosine when applied together. The in vivo infection experiments revealed a high susceptibility of CF mice to pulmonary infection with S. aureus. Inhalation of C18-sphingosine rescued CF mice from pulmonary infections with different clinical S. aureus isolates, including a methicillin-resistant S. aureus (MRSA) strain.

CONCLUSIONS

Our data indicate that the imbalance between ceramide and sphingosine in the CF respiratory tract prevents killing of S. aureus and causes the high susceptibility of CF mice to pulmonary S. aureus infections.

Antinociceptive effects of FTY720 during trauma-induced neuropathic pain are mediated by spinal S1P receptors

FTY720 (fingolimod) is, after its phosphorylation by sphingosine kinase (SPHK) 2, a potent, non-selective sphingosine-1-phosphate (S1P) receptor agonist. FTY720 has been shown to reduce the nociceptive behavior in the paclitaxel model for chemotherapy-induced neuropathic pain through downregulation of S1P receptor 1 (S1P1) in microglia of the spinal cord. Here, we investigated the mechanisms underlying the antinociceptive effects of FTY720 in a model for trauma-induced neuropathic pain. We found that intrathecal administration of phosphorylated FTY720 (FTY720-P) decreased trauma-induced pain behavior in mice, while intraplantar administered FTY720-P had no effect. FTY720-P, but not FTY720, reduced the nociceptive behavior in SPHK2-deficient mice, suggesting the involvement of S1P receptors. Fittingly, intrathecal administration of antagonists for S1P1 or S1P3, W146 and Cay10444 respectively, abolished the antinociceptive effects of systemically administered FTY720, demonstrating that activation of both receptors in the spinal cord is necessary to induce antinociceptive effects by FTY720. Accordingly, intrathecal administration of S1P1 receptor agonists was not sufficient to evoke an antinociceptive effect. Taken together, the data show that, in contrast to its effects on chemotherapy-induced neuropathy, FTY720 reduces trauma-induced neuropathic pain by simultaneous activation of spinal S1P1 and S1P3 receptor subtypes.

Cbl-b-deficient mice express alterations in trafficking-related molecules but retain sensitivity to the multiple sclerosis therapeutic agent, FTY720

The variable response to therapy in multiple sclerosis (MS) suggests a need for personalized approaches based on individual genetic differences. GWAS have linked CBLB gene polymorphisms with MS and recent evidence demonstrated that these polymorphisms can be associated with abnormalities in T cell function and response to interferon-β therapy. Cbl-b is an E3 ubiquitin ligase that regulates T cell activation and Cbl-b-deficient (Cbl-b(-/-)) mice show T cell abnormalities described in MS patients. We now show that Cbl-b(-/-) T cells demonstrate significant lymph node trafficking abnormalities. We thus asked whether the MS-approved drug, FTY720, postulated to trap T cells in lymphoid tissues, is less effective in the context of Cbl-b dysfunction. We now report that FTY720 significantly inhibits EAE in Cbl-b(-/-) mice. Our results newly document a role for Cbl-b in T cell trafficking but suggest nevertheless that MS patients with Cbl-b abnormalities may still be excellent candidates for FTY720 treatment.

Emerging biology of sphingosine-1-phosphate: its role in pathogenesis and therapy

Membrane sphingolipids are metabolized to sphingosine-1-phosphate (S1P), a bioactive lipid mediator that regulates many processes in vertebrate development, physiology, and pathology. Once exported out of cells by cell-specific transporters, chaperone-bound S1P is spatially compartmentalized in the circulatory system. Extracellular S1P interacts with five GPCRs that are widely expressed and transduce intracellular signals to regulate cellular behavior, such as migration, adhesion, survival, and proliferation. While many organ systems are affected, S1P signaling is essential for vascular development, neurogenesis, and lymphocyte trafficking. Recently, a pharmacological S1P receptor antagonist has won approval to control autoimmune neuroinflammation in multiple sclerosis. The availability of pharmacological tools as well as mouse genetic models has revealed several physiological actions of S1P and begun to shed light on its pathological roles. The unique mode of signaling of this lysophospholipid mediator is providing novel opportunities for therapeutic intervention, with possibilities to target not only GPCRs but also transporters, metabolic enzymes, and chaperones.

Improving reconstituted HDL composition for efficient post-ischemic reduction of ischemia reperfusion injury

BACKGROUND

New evidence shows that high density lipoproteins (HDL) have protective effects beyond their role in reverse cholesterol transport. Reconstituted HDL (rHDL) offer an attractive means of clinically exploiting these novel effects including cardioprotection against ischemia reperfusion injury (IRI). However, basic rHDL composition is limited to apolipoprotein AI (apoAI) and phospholipids; addition of bioactive compound may enhance its beneficial effects.

OBJECTIVE

The aim of this study was to investigate the role of rHDL in post-ischemic model, and to analyze the potential impact of sphingosine-1-phosphate (S1P) in rHDL formulations.

METHODS AND RESULTS

The impact of HDL on IRI was investigated using complementary in vivo, ex vivo and in vitro IRI models. Acute post-ischemic treatment with native HDL significantly reduced infarct size and cell death in the ex vivo, isolated heart (Langendorff) model and the in vivo model (-48%, p<0.01). Treatment with rHDL of basic formulation (apoAI + phospholipids) had a non-significant impact on cell death in vitro and on the infarct size ex vivo and in vivo. In contrast, rHDL containing S1P had a highly significant, protective influence ex vivo, and in vivo (-50%, p<0.01). This impact was comparable with the effects observed with native HDL. Pro-survival signaling proteins, Akt, STAT3 and ERK1/2 were similarly activated by HDL and rHDL containing S1P both in vitro (isolated cardiomyocytes) and in vivo.

CONCLUSION

HDL afford protection against IRI in a clinically relevant model (post-ischemia). rHDL is significantly protective if supplemented with S1P. The protective impact of HDL appears to target directly the cardiomyocyte.

[Fingolimod treatment in multiple sclerosis]

Multiple sclerosis (MS), an inflammatory disorder of the central nervous system, is characterized by relapsing-remitting (RR) clinical course. Fingolimod was the first oral therapy to prevent relapses in patients with RRMS, approved in Japan in 2011. In lymph node, fingolimod acts as functional antagonist, leading to internalization of sphingosine-1-phosphate 1(S1P1) receptors of lymphocytes. Lymphocytes in lymph nodes bearing S1P1 receptors cannot egress from lymph nodes. As a result, lymphocyte count in the circulation is reduced. Fingolimod showed reduced relapses, and suppressed the number of enhancing lesion and the progression of brain atrophy of brain MRI, however, it also showed some adverse effects such as bradycardia, herpes zoster infection, macular edema, liver dysfunction, and teratogenic properties. We proposed indications of fingolimod therapy, and reduced dosage therapy of fingolimod for patients with a lymphocyte count below 0.2 x 10(9) cells/L.

Compositional changes of B and T cell subtypes during fingolimod treatment in multiple sclerosis patients: a 12-month follow-up study

Background and objective

The long term effects of fingolimod, an oral treatment for relapsing-remitting (RR) multiple sclerosis (MS), on blood circulating B and T cell subtypes in MS patients are not completely understood. This study describes for the first time the longitudinal effects of fingolimod treatment on B and T cell subtypes. Furthermore, expression of surface molecules involved in antigen presentation and costimulation during fingolimod treatment are assessed in MS patients in a 12 month follow-up study.

Methods

Using flow cytometry, B and T cell subtypes, and their expression of antigen presentation, costimulation and migration markers were measured during a 12 month follow-up in the peripheral blood of MS patients. Data of fingolimod-treated MS patients (n = 49) were compared to those from treatment-naive (n = 47) and interferon-treated (n = 27) MS patients.

Results

In the B cell population, we observed a decrease in the proportion of non class-switched and class-switched memory B cells (p<0.001), both implicated in MS pathogenesis, while the proportion of naive B cells was increased during fingolimod treatment in the peripheral blood (PB) of MS patients (p<0.05). The remaining T cell population, in contrast, showed elevated proportions of memory conventional and regulatory T cells (p<0.01) and declined proportions of naive conventional and regulatory cells (p<0.05). These naive T cell subtypes are main drivers of MS pathogenesis. B cell expression of CD80 and CD86 and programmed death (PD) -1 expression on circulating follicular helper T cells was increased during fingolimod follow-up (p<0.05) pointing to a potentially compensatory mechanism of the remaining circulating lymphocyte subtypes that could provide additional help during normal immune responses.

Conclusions

MS patients treated with fingolimod showed a change in PB lymphocyte subtype proportions and expression of functional molecules on T and B cells, suggesting an association with the therapeutic efficacy of fingolimod.

Persistence with and adherence to fingolimod compared with other disease-modifying therapies for the treatment of multiple sclerosis: a retrospective US claims database analysis

OBJECTIVE

Achieving therapeutic goals in multiple sclerosis (MS) requires strict adherence to treatment schedules. This retrospective study analyzed persistence with, and adherence to, fingolimod compared with injectable/infusible disease-modifying therapies (DMTs) in patients with MS.

METHODS

Patients in the PharMetrics Plus™ US administrative claims database with at least one prescription for, or administration of, fingolimod, glatiramer acetate (GA), interferon (IFN), or natalizumab (index DMT) between October 1, 2010 and September 30, 2011 were included. Patients were naïve to index DMT (no claim in the previous 360 days) and had an MS diagnosis code within 360 days of the first index DMT prescription. Outcomes were persistence, risk of discontinuing index DMT (evaluated by a Cox proportional hazards model), adherence (measured using the medication possession ratio [MPR] and proportion of days covered [PDC] in patients with at least two index DMT prescriptions), and the risk of being non-adherent (MPR <80% and PDC <80%, assessed using a logistic regression model).

RESULTS

The study included 3750 patients (fingolimod, n = 889; GA, n = 1233; any IFN, n = 1341; natalizumab, n = 287). Discontinuation rates (fingolimod, 27.9%; GA, 39.5%; IFN, 43.7%; natalizumab, 39.5%; all p < 0.001) and risk of discontinuation were significantly higher (hazard ratios vs fingolimod [95% confidence interval]: GA, 1.75 [1.49-2.07]; IFN, 2.01 [1.71-2.37]; natalizumab, 1.53 [1.22-1.91]) for patients receiving other DMTs compared with fingolimod. The risk of being non-adherent was also lower for patients in the fingolimod cohort than the other treatment cohorts, irrespective of whether non-adherence was defined as MPR <80% (p < 0.05 for all) or PDC <80% (p < 0.05 for GA and IFN).

LIMITATIONS

As with all studies assessing real-world treatment patterns it is unclear if medications were used as prescribed.

CONCLUSIONS

In a real-world setting, persistence with, and adherence to, oral fingolimod was higher than for injectable and infusible DMTs.

Previous treatment influences fingolimod efficacy in relapsing-remitting multiple sclerosis: results from an observational study

OBJECTIVE

Fingolimod (FTY) is licensed as a disease-modifying treatment in highly active relapsing-remitting multiple sclerosis. The aim of the study was to evaluate the efficacy and safety of FTY in a real-life setting and to explore the possible role of clinical and MRI parameters, including previous treatment type, in predicting its efficacy.

METHODS

Clinical and MRI data was collected on 127 patients assigned to treatment with FTY in six multiple sclerosis centers in Emilia-Romagna, Italy, between August 2011 and June 2013.

RESULTS

During a mean follow-up period of 10 months (range 1-22), we observed a total of 47 relapses in 39 patients (30.7%); new T2 lesions or gadolinium-enhancing (Gd+) lesions were present at follow-up MRI in 32/71 patients (45%). Expanded disability status scale (EDSS) at the end of the follow-up period was not different when compared to the baseline EDSS. Serious adverse events occurred in three patients (2.4%). A higher proportion of patients previously treated with natalizumab showed clinical (41%) or MRI activity (54%). Previous treatment with natalizumab increased the risk of a relapse within 30 days (versus immunomodulatory drugs; OR: 4.3; p = 0.011) and at survival analysis (versus remaining patients; HR: 1.9; p = 0.046). Study limitations include a small population sample, a short observation period with variable timing of follow-up MRI and different baseline characteristics of patients previously treated with natalizumab compared to those treated with immunomodulatory drugs.

CONCLUSIONS

This study confirms the efficacy of FTY in reducing relapse rate in patients previously treated with immunomodulatory drugs, while it seems to be less effective in patients discontinuing natalizumab. Due to the short duration of follow-up it is not possible to evaluate disability progression; however, no difference was observed between the groups.

Testing Aβ toxicity on primary CNS cultures using drug-screening microfluidic chips

Open microscale cultures of primary central nervous system (CNS) cells have been implemented in microfluidic chips that can expose the cells to physiological fluidic shear stress conditions. Cells in the chips were exposed to differently aggregated forms of beta-amyloid (Aβ), i.e. conditions mimicking an Alzheimer's Disease environment, and treated with CNS drugs in order to assess the contribution of glial cells during pharmacological treatments. FTY720, a drug approved for the treatment of Multiple Sclerosis, was found to play a marked neuroprotective role in neuronal cultures as well as in microglia-enriched neuronal cultures, preventing neurodegeneration after cell exposure to neurotoxic oligomers of Aβ.

Frequency and economic impact of comorbid cardiac conditions with multiple sclerosis

BACKGROUND

Fingolimod, an oral immunomodulatory therapy approved to treat multiple sclerosis (MS) is contraindicated in patients with certain cardiac conditions, yet the frequency of these conditions in patients with MS is not known. This study assessed the frequency and economic impact of cardiac conditions among hospitalizations of patients with MS.

OBJECTIVE

To determine the frequency and economic impact of selected comorbid cardiac conditions among hospitalizations of patients with a diagnosis of MS.

METHODS

This was a retrospective, discharge-level cohort study of hospital discharge data from 2006-2010. The frequencies of cardiac conditions of interest (based on contraindications to fingolimod in the prescribing information) were reported among all discharges with a diagnosis of MS. Two cohorts were defined: (1) MS with cardiac condition of interest and (2) MS with no cardiac condition of interest. The mean adjusted cost per discharge and incremental cost per hospital day were reported.

RESULTS

Among 136,542 discharges with a diagnosis of MS, 9.2% (n = 12,504) had a comorbid cardiac condition of interest based on contraindications to fingolimod in the prescribing information. Heart failure (59.4%), myocardial infarction (17.2%), and occlusion of cerebral arteries (12.4%) were the most common cardiac conditions. The mean adjusted cost per discharge was significantly higher for the MS with cardiac condition cohort compared with the MS with no cardiac condition cohort ($17,623 vs. $11,663, P  less than  0.0001). The incremental cost per hospital day was $6,479 for the MS with cardiac condition cohort. 

CONCLUSIONS

The presence of comorbid cardiac conditions among hospital discharges in patients with MS is substantial and associated with higher hospitalization costs. Health plans should give consideration to the overlapping presence of these diseases when determining coverage criteria for immunomodulatory therapies and designing clinical programs for MS.

Central effects of fingolimod

INTRODUCTION

Fingolimod, a sphingosine-1-phosphate receptor modulator, was the first oral therapy approved for relapsing-remitting multiple sclerosis, and shows a novel mechanism of action. Upon binding to S1P1 receptors in lymphocytes, the selective retention of naive and central memory T cells in secondary lymphoid tissues is promoted, preventing their egress to the central nervous system (CNS). In addition, fingolimod readily crosses the blood brain barrier, and several reports suggest a direct neuroprotective effect in the CNS.

AIM

To review the available data on the central effects of fingolimod.

DEVELOPMENT

Imbalances between damage and repair processes are a reflection of chronic demyelination, axonal degeneration and gliosis, and seem to contribute to multiple sclerosis associated disability. Given fingolimod readily crosses the blood brain barrier, it can exert its action directly on S1P receptors present in CNS cells. Fingolimod occupies S1P receptors in oligodendrocytes, oligodendrocyte precursor cells, astrocytes, microglial cells and neurons, promoting remyelination, neuroprotection, and endogenous regeneration processes. Efficacy results from clinical trials are consistent with a mechanism of action that includes direct effects in CNS cells.

CONCLUSIONS

Current evidence suggests that the efficacy of fingolimod in the treatment of Multiple Sclerosis is due to its dual action as an immunomodulatory molecule and as a direct modulator of S1PRs in the CNS. In fact, recent reports propose that fingolimod has neuroprotective effects in several models, and open new avenues of potential therapeutic applications, such as Alzheimer's disease, cerebral malaria, neuroblastoma and neuroprotection in cranial irradiation.

Healthcare resource use and relapses with fingolimod versus natalizumab for treating multiple sclerosis: a retrospective US claims database analysis

OBJECTIVE

Healthcare resource utilization in patients with multiple sclerosis (MS) is linked to relapses and disease progression. This retrospective cohort database analysis compared healthcare resource use and proxy measures of relapse outcomes in patients with active disease who switched to fingolimod or natalizumab.

METHODS

Using administrative claims data from the US PharMetrics Plus database, we identified patients with an MS diagnosis and a claim for fingolimod or natalizumab between 1 October 2010 and 30 June 2012 (index period) who had experienced a relapse (identified using a claims-based algorithm) and used other disease-modifying therapies (DMTs) in the previous year. Patients in the fingolimod and natalizumab cohorts were propensity score matched (1:1). MS-related inpatient stays, corticosteroid use and the proportion of patients experiencing claims-based relapses were assessed in the pre-index and post-index persistence periods. Time to first claims-based relapse in the post-index persistence period was assessed using a Kaplan-Meier curve.

RESULTS

The study included 623 unmatched patients (299 and 324 patients in the fingolimod and natalizumab cohorts, respectively) and 370 matched patients (185 in each cohort). In the matched analysis, MS-related inpatient stays and corticosteroid use were similar in the fingolimod and natalizumab cohorts during the post-index persistence period, and were significantly reduced versus the pre-index period (p < 0.01). A similar proportion of patients in the fingolimod and natalizumab cohorts were free from claims-based relapses in the persistence period (68.1% and 68.6%, respectively). There was no significant difference in the likelihood of experiencing a claims-based relapse (p = 0.8696).

LIMITATION

Identification of relapses is based on database claims rather than on clinical assessment.

CONCLUSIONS

In analyses of patients with MS with a history of relapse and DMT use, fingolimod and natalizumab reduce healthcare resource utilization and have similar effectiveness in a real-world setting.

[[Natalizumab therapy, 2013]

Multiple sclerosis (MS) is the most common chronic disease of the central nervous system in young adults. No curative therapy is known. Currently, six drugs are available that can reduce the activity of MS. The first-line drugs can completely reduce the activity of the disease in nearly two-thirds of the patients. In the remainder, who suffer from breakthrough disease, the condition of the patient worsens, and second-line therapies must be used. The second-line drug natalizumab exhibits almost double efficacy of the first-line drugs, but also have less favourable adverse effects. As a severe side-effect for instance, natalizumab carries the risk of the development of progressive multifocal leucoencephalopathy (PML), caused by a polyoma virus, the JC virus. There are three major risk factors for PML: an anti-JCV antibody status, a long duration of natalizumab treatment and prior immunosuppressant therapy. The lowest-risk group (1:14,286) comprises of patients who are anti-JCV antibody-negative, in whom the prior immunosuppressant use and duration of natalizumab therapy do not influence the risk of PML. With no prior immunosuppressant treatment, the incidence of PML increases to 1 in 192 patients after 2 years among those who are anti-JCV antibody-positive. These data may lead the physician to decide to discontinue natalizumab treatment. The half-life of natalizumab is three months; during this time other therapies can not be administered and the patients encounter the rebound effect: as the patients receiving natalizumab therapy displayed a high disease activity before treatment, the rebound effect can lead to relapses. After the termination of natalizumab second-line disease-modifying therapy with fingolimod may be introduced; no PML cases occur in response to fingolimod treatment. In the large majority of patients taking natalizumab who do not develop PML, this drug is highly effective and can prevent the progression of MS. The benefit of therapy and the risk of PML must be considered on an individual basis, with regard to the disease activity, the progression and the MRI activity, before natalizumab therapy is implemented.

FTY720 induces apoptosis of M2 subtype acute myeloid leukemia cells by targeting sphingolipid metabolism and increasing endogenous ceramide levels

The M2 subtype Acute Myeloid Leukemia (AML-M2) with t(8;21) represents an unmet challenge because of poor clinical outcomes in a sizable portion of patients. In this study,we report that FTY720 (Fingolimod), a sphingosine analogue and an FDA approved drug for treating of multiple sclerosis, shows antitumorigenic activity against the Kasumi-1 cell line, xenograft mouse models and leukemic blasts isolated from AML-M2 patients with t(8;21) translocation. Primary investigation indicated that FTY720 caused cell apoptosis through caspases and protein phosphatase 2A (PP2A) activation. Transcriptomic profiling further revealed that FTY720 treatment could upregulate AML1 target genes and interfere with genes involved in ceramide synthesis. Treatment with FTY720 led to the elimination of AML1-ETO oncoprotein and caused cell cycle arrest. More importantly, FTY720 treatment resulted in rapid and significant increase of pro-apoptotic ceramide levels, determined by high-performance liquid chromatography-electrospray ionization tandem mass spectrometry based lipidomic approaches. Structural simulation model had also indicated that the direct binding of ceramide to inhibitor 2 of PP2A (I2PP2A) could reactivate PP2A and cause cell death. This study demonstrates, for the first time, that accumulation of ceramide plays a central role in FTY720 induced cell death of AML-M2 with t(8;21). Targeting sphingolipid metabolism by using FTY720 may provide novel insight for the drug development of treatment for AML-M2 leukemia.

Efficacy and safety of BG-12 (dimethyl fumarate) and other disease-modifying therapies for the treatment of relapsing-remitting multiple sclerosis: a systematic review and mixed treatment comparison

OBJECTIVE

Currently, direct comparative evidence or head-to-head data between BG-12 (dimethyl fumarate) and other disease-modifying treatments (DMTs) is limited. This study is a systematic review and data synthesis of published randomized clinical trials comparing the efficacy and safety of existing DMTs to BG-12 for relapsing-remitting multiple sclerosis (RRMS).

METHODS

A systematic review was conducted by searching MEDLINE, EMBASE, and the Cochrane Library for English-language publications from 1 January 1960 to 15 November 2012. Clinicaltrials.gov, metaRegister of Controlled Trials, and conference proceedings from relevant annual symposia were also hand searched. Two independent reviewers collected and extracted data, with discrepancies reconciled by a third reviewer. Included studies were randomized controlled trials (RCTs) of DMTs (interferon [IFN] beta-1a, IFN beta-1b, glatiramer acetate [GA], BG-12, fingolimod, natalizumab, and teriflunomide) in adults with RRMS. Mixed treatment comparisons were conducted to derive the relative effect size for the included treatments. Annualized relapse rate (ARR), disability progression, and safety outcomes were assessed.

RESULTS

BG-12 240 mg twice a day (BID) significantly reduces ARR compared to placebo (rate ratio: 0.529 [95% CI: 0.451-0.620]), IFNs (0.76 [95% CI: 0.639-0.904]), GA (0.795 [95% CI: 0.668-0.947]), and teriflunomide 7 mg and 14 mg (0.769 [95% CI: 0.610-0.970] and 0.775 [95% CI: 0.614-0.979]), and does not show a significant difference when compared to fingolimod. Only natalizumab was significantly superior to BG-12 in reducing ARR. BG-12 also demonstrated favorable results for disability and safety outcomes.

CONCLUSION

Based on indirect comparison, BG-12 offers an effective oral treatment option for patients with RRMS with an overall promising efficacy and safety profile compared to currently approved DMTs. Key limitations of the systematic review were the large heterogeneity in patients enrolled and the variability in the definition of outcomes in included trials.

Pregnancy outcomes in the clinical development program of fingolimod in multiple sclerosis

OBJECTIVE

To report outcomes of pregnancies that occurred during the fingolimod clinical development program.

METHODS

Pregnancy outcomes from phase II, phase III, and phase IV clinical studies (with optional extensions) were reported by clinical trial investigators. Fingolimod exposure in utero was defined as fingolimod treatment at the time of conception or in the 6 weeks before conception.

RESULTS

As of October 31, 2011, 89 pregnancies were reported in completed or ongoing clinical studies, with 74 in fingolimod treatment arms. Of 66 pregnancies with in utero exposure to fingolimod, there were 28 live births, 9 spontaneous abortions, 24 elective abortions, 4 ongoing pregnancies, and 1 pregnancy with an unknown outcome (patient lost to follow-up). Two infants were born with malformations: 1 with congenital unilateral posteromedial bowing of the tibia and 1 with acrania. Elective abortions were performed for 1 case each of tetralogy of Fallot, spontaneous intrauterine death, and failure of fetal development. There were 5 cases (7.6%; 95% confidence interval 3%-17%) of abnormal fetal development in the 66 pregnancies that had in utero exposure to fingolimod. In all 5 cases, fetal exposure to the drug took place in the first trimester of pregnancy.

CONCLUSIONS

The number of patients becoming pregnant during fingolimod therapy remains small and does not permit firm conclusions to be drawn about fetal safety of fingolimod in humans. Given the known risks of teratogenicity in animals and the present data, women of childbearing potential should use effective contraception during fingolimod therapy and for 2 months after discontinuation.

Relapse rates in patients with multiple sclerosis switching from interferon to fingolimod or glatiramer acetate: a US claims database study

BACKGROUND

Approximately one-third of patients with multiple sclerosis (MS) are unresponsive to, or intolerant of, interferon (IFN) therapy, prompting a switch to other disease-modifying therapies. Clinical outcomes of switching therapy are unknown. This retrospective study assessed differences in relapse rates among patients with MS switching from IFN to fingolimod or glatiramer acetate (GA) in a real-world setting.

METHODS

US administrative claims data from the PharMetrics Plus™ database were used to identify patients with MS who switched from IFN to fingolimod or GA between October 1, 2010 and March 31, 2012. Patients were matched 1∶1 using propensity scores within strata (number of pre-index relapses) on demographic (e.g. age and gender) and disease (e.g. timing of pre-index relapse, comorbidities and symptoms) characteristics. A claims-based algorithm was used to identify relapses while patients were persistent with therapy over 360 days post-switch. Differences in both the probability of experiencing a relapse and the annualized relapse rate (ARR) while persistent with therapy were assessed.

RESULTS

The matched sample population contained 264 patients (n = 132 in each cohort). Before switching, 33.3% of patients in both cohorts had experienced at least one relapse. During the post-index persistence period, the proportion of patients with at least one relapse was lower in the fingolimod cohort (12.9%) than in the GA cohort (25.0%), and ARRs were lower with fingolimod (0.19) than with GA (0.51). Patients treated with fingolimod had a 59% lower probability of relapse (odds ratio, 0.41; 95% confidence interval [CI], 0.21-0.80; p = 0.0091) and 62% fewer relapses per year (rate ratio, 0.38; 95% CI, 0.21-0.68; p = 0.0013) compared with those treated with GA.

CONCLUSIONS

In a real-world setting, patients with MS who switched from IFNs to fingolimod were significantly less likely to experience relapses than those who switched to GA.

Assessment of cardiac safety during fingolimod treatment initiation in a real-world relapsing multiple sclerosis population: a phase 3b, open-label study

The aim of this study was to evaluate short-term safety and tolerability of fingolimod in a real-world population with relapsing multiple sclerosis, focusing on cardiac safety during treatment initiation. Patients received fingolimod 0.5 mg once daily for four months. Patients excluded from the pivotal studies with certain pre-existing cardiac conditions or baseline cardiac findings (PCCs), and those receiving beta blockers (BBs) and/or calcium channel blockers (CCBs), were eligible. Heart rate (HR) and electrical conduction events were monitored using ambulatory electrocardiography for at least 6 h after the first dose. Of 2,417 enrolled patients, 2,282 (94.4 %) completed the study. Fingolimod initiation was associated with a transient, mostly asymptomatic decrease in HR. Bradycardia adverse events occurred in 0.6 % of patients and were more frequent in individuals receiving BBs/CCBs (3.3 %) than in other patient subgroups (0.5-1.4 %); most events were asymptomatic, and all patients recovered without pharmacological intervention. In the 6 h post-dose, the incidences of Mobitz type I second-degree atrioventricular block (AVB) and 2:1 AVB were higher in patients with PCCs (4.1 and 2.0 %, respectively) than in those without (0.9 and 0.3 %, respectively); at pre-dose screening, patients with PCCs had the same incidence of Mobitz type I second-degree AVB (4.1 %) and a slightly lower incidence of 2:1 AVB (0.7 %) than 6 h post-dose. All recorded conduction abnormalities were asymptomatic. This study adds to the evidence showing that cardiac effects during fingolimod initiation remain consistent with those known from previous, controlled studies, even if patients with PCCs are included.

Fingolimod (FTY720) therapy in Japanese patients with relapsing multiple sclerosis over 12 months: results of a phase 2 observational extension

BACKGROUND

A 6-month phase 2 study of fingolimod demonstrated efficacy and safety in Japanese patients with relapsing-remitting multiple sclerosis (MS). Here we report a 6-month observational extension that evaluated efficacy and safety in patients who received fingolimod continuously for 12 months or who switched from placebo to fingolimod.

METHODS

Of 147 patients who completed the 6-month core study, 143 entered the extension. Those originally randomized to placebo were re-randomized to fingolimod 1.25 mg or 0.5 mg. During the extension, all patients were switched to open-label fingolimod 0.5 mg.

RESULTS

Magnetic resonance imaging (MRI) and relapse outcomes were maintained or improved in patients treated with fingolimod for 12 months versus those treated for 6 months. No new safety events were reported over 12 months of treatment. Infections occurred in similar proportions of continuously treated and switched patients, while cardiac and liver adverse events occurred in fewer continuously treated than switched patients. Four patients were aquaporin-4 (AQP4) antibody-positive, three of whom showed rapid disease exacerbations within 10 days of fingolimod initiation.

CONCLUSION

Continuous fingolimod treatment for up to 12 months was associated with maintained or improved efficacy and a manageable safety profile, consistent with that previously seen. Results in a small number of patients suggest lack of benefit in AQP4 antibody-positive patients. Meaningful statistical interpretation was limited by the small sample size in each treatment group, owing to the number of patients who completed the core study.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00670449.

Changes in Th17 and regulatory T cells after fingolimod initiation to treat multiple sclerosis

Fingolimod has demonstrated efficacy in patients with multiple sclerosis (MS), and patients become gradually lymphopenic after a few days of treatment, with selective reductions in CD4+ subsets. We observed an increase in the frequencies of circulating regulatory T cells after fingolimod administration. However, we also found that half of patients had increased proportion of circulating Th17 cells in CD4+ T cells after treatment (including a patient with MS relapses), whereas the others showed lower frequencies of Th17 cells, indicating some variability among patients. Further studies may confirm if slower reduction of circulating Th17 cells following fingolimod initiation predisposes to relapses.

[Usefulness of electronic drug registers: Spanish register of patients treated with fingolimod (Gilenya ®)]

INTRODUCTION

This study outlines the design of an electronic register of patients with multiple sclerosis who began treatment with fingolimod in Spain. The system is intended to serve as a tool to monitor its utilisation in daily clinical practice and thus allow optimisation of the way it is used.

AIMS

To establish the profile of patients with multiple sclerosis undergoing treatment with fingolimod and to determine the effectiveness and safety of this treatment in daily clinical practice.

DEVELOPMENT

An observation-based, retrospective and prospective, multi-centre registry is set up, which will be active for five years. Forty neurologists working in Spain will participate in the project. Patients treated with fingolimod who fulfil the selection criteria will be included in the study. The effectiveness variables that will be evaluated are: disability measured by means of the Expanded Disability Status Scale, the rate of attacks, T1 gadolinium-enhancing lesions and new lesions in T2, and the percentage of patients who were free of activity and those who require concomitant treatments. The tolerability variables that will be evaluated are: the rate of patients who present events and adverse reactions, respectively, with a separate analysis of those presenting after the first dose or that are related to the fingolimod risk management plan and the treatment dropout rate.

CONCLUSIONS

New pharmaceuticals that have only recently been commercialised require more information about their effectiveness and safety, beyond the controlled environment of a clinical trial. Initiatives involving electronic registries such as the Gilenya register are a solution that can respond to such needs by providing information in the shortest possible time about the most suitable management in order to be able to make the best and most efficient use of it.

Cytokine storm plays a direct role in the morbidity and mortality from influenza virus infection and is chemically treatable with a single sphingosine-1-phosphate agonist molecule

Cytokine storm defines a dysregulation of and an excessively exaggerated immune response most often accompanying selected viral infections and several autoimmune diseases. Newly emerging and re-emerging infections of the respiratory tract, especially influenza, SARS, and hantavirus post considerable medical problems. Their morbidities and mortalities are often a direct result of cytokine storm. This chapter visits primarily influenza virus infection and resultant cytokine storm. It provides the compelling evidence that illuminates cytokine storm in influenza pathogenesis and the clear findings that cytokine storm is chemically tractable by therapy directed toward sphingosine-1-phosphate receptor (S1PR) modulation, specifically S1P1R agonist therapy. The mechanism(s) of how S1P1R signaling works and the pathways involved are subjects of this review.

Diffusion tensor imaging detects treatment effects of FTY720 in experimental autoimmune encephalomyelitis mice

Fingolimod (FTY720) is an orally available sphingosine-1-phosphate (S1P) receptor modulator reducing relapse frequency in patients with relapsing-remitting multiple sclerosis (RRMS). In addition to immunosuppression, neuronal protection by FTY720 has also been suggested, but remains controversial. Axial and radial diffusivities derived from in vivo diffusion tensor imaging (DTI) were employed as noninvasive biomarkers of axonal injury and demyelination to assess axonal protection by FTY720 in experimental autoimmune encephalomyelitis (EAE) mice. EAE was induced through active immunization of C57BL/6 mice using myelin oligodendrocyte glycoprotein peptide 35-55 (MOG(35-55)). We evaluated both the prophylactic and therapeutic treatment effect of FTY720 at doses of 3 and 10 mg/kg on EAE mice by daily clinical scoring and end-point in vivo DTI. Prophylactic administration of FTY720 suppressed the disease onset and prevented axon and myelin damage when compared with EAE mice without treatment. Therapeutic treatment by FTY720 did not prevent EAE onset, but reduced disease severity, improving axial and radial diffusivity towards the control values without statistical significance. Consistent with previous findings, in vivo DTI-derived axial and radial diffusivity correlated with clinical scores in EAE mice. The results support the use of in vivo DTI as an effective outcome measure for preclinical drug development.

An update on new and emerging therapies for relapsing-remitting multiple sclerosis

Disease-modifying therapies (DMTs), known to actively reduce relapses and delay disability progression, have been used for the treatment of relapsing-remitting multiple sclerosis (RRMS) for over a decade. These well-known therapies include intramuscular (IM) interferon (IFN) beta-1a (Avonex), subcutaneous (SC) IFN beta-1a (Rebif), SC IFN beta- 1b (Betaseron; Extavia), and SC glatiramer acetate (Copaxone). These first-line therapies have shown only partial benefits for controlling multiple sclerosis (MS) disease activity and are often associated with inadequate patient adherence. Low patient adherence to therapy may be related to the mode of administration or to the side effects associated with treatment. The intravenous DMT natalizumab (Tysabri; dosed monthly) provides high therapeutic efficacy and good compliance but is considered a second-line intervention because of the associated increased risk for progressive multifocal leukoencephalopathy. In 2010, fingolimod (Gilenya), the first oral DMT, was approved by the US Food and Drug Administration (FDA) for the treatment of MS. Recently, 2 new oral DMTs received FDA approval for the treatment of RRMS: teriflunomide (Aubagio) and dimethyl fumarate (Tecfidera). In addition, oral laquinimod, several monoclonal antibodies (eg, alemtuzumab, daclizumab, and ocrelizumab), and other agents have shown preliminary beneficial results in relapsing MS in phase 3 clinical trials. These new and emerging DMTs may provide a more efficacious individualized therapeutic approach, more favorable methods of administration (eg, oral administration), and/or a lower frequency of infusions (eg, annually, 3-5 daily infusions over a year for alemtuzumab) that may improve patient adherence and clinical outcomes.

Cost minimisation analysis of fingolimod vs natalizumab as a second line of treatment for relapsing-remitting multiple sclerosis

INTRODUCTION

At present, there is a lack of economic assessments of second-line treatments for relapsing-recurring multiple sclerosis. The aim of this study was to compare the efficiency between fingolimod and natalizumab in Spain.

METHODS

A cost minimisation analysis model was developed for a 2-year horizon. The same relapse rate was applied to both treatment arms and the cost of resources was calculated using Spain's stipulated rates for 2012 in euros. The analysis was conducted from the perspective of Spain's national health system and an annual discount rate of 3% was applied to future costs. A sensitivity analysis was performed to validate the robustness of the model.

RESULTS

Indirect comparison of fingolimod with natalizumab revealed no significant differences (hazard ratio between 0.82 and 1.07). The total direct cost, considering a 2-year analytical horizon, a 7.5% discount stipulated by Royal Decree, and a mean annual relapse rate of 0.22, was € 40914.72 for fingolimod and € 45890.53 for natalizumab. Of the total direct costs that were analysed, the maximum cost savings derived from prescribing fingolimod prescription was € 4363.63, corresponding to lower administration and treatment maintenance costs. Based on the sensitivity analysis performed, fingolimod use was associated with average savings of 11% (range 3.1%-18.7%).

CONCLUSIONS

Fingolimod is more efficient than natalizumab as a second-line treatment option for relapsing-remitting multiple sclerosis and it generates savings for the Spanish national health system.

Cationic ceramides and analogues, LCL30 and LCL85, as adjuvants to photodynamic therapy of tumors

Photodynamic therapy (PDT) is known to alter the expression of various genes in treated cells. This prompted us to examine the activity of genes encoding two important enzymes in sphingolipid (SL) metabolism, dihydroceramide desaturase (DES) and sphingosine kinase (SPHK), in mouse SCCVII tumor cells treated by PDT using either the porphyrin-based photosensitizer Photofrin or silicon phthalocyanine Pc4. The results revealed that PDT induced an upregulation in the expression of two major isoforms of both genes (DES1 and DES2 as well as SPHK1 and SPHK2). While the changes were generally moderate (2-3-fold gains), the increase in DES2 expression was more pronounced and it was much greater with Photofrin-PDT than with Pc4-PDT (over 23-fold vs. less than 5-fold). Combining either Photofrin-PDT or Pc4-PDT with the cationic C16-ceramide LCL30 (20mg/kg i.p.) for treatment of subcutaneously growing SCCVII tumors rendered important differences in the therapy outcome. Photofrin-PDT, used at a dose that attained good initial response but no tumor cures, produced 50% cures when combined with a single LCL30 treatment. In contrast, the same LCL30 treatment combined with Pc4-PDT had no significant effect on tumor response. The optimal timing of LCL30 injection was immediately after Photofrin-PDT. The therapeutic benefit was lost when LCL30 was given in two 20mg/kg injections encompassing intervals before and after PDT. LCL85, the cationic B13 ceramide analogue and SL-modulating agent, also increased cure rates of Photofrin-PDT treated tumors, but the therapeutic benefit was less pronounced than with LCL30. These results with LCL30 and LCL85, and our previous findings for LCL29 (another SL analogue), assert the potential of SLs for use as adjuvants to augment the efficacy of PDT-mediated tumor destruction.

Sphingosine-1-phosphate, FTY720, and sphingosine-1-phosphate receptors in the pathobiology of acute lung injury

Acute lung injury (ALI) attributable to sepsis or mechanical ventilation and subacute lung injury because of ionizing radiation (RILI) share profound increases in vascular permeability as a key element and a common pathway driving increased morbidity and mortality. Unfortunately, despite advances in the understanding of lung pathophysiology, specific therapies do not yet exist for the treatment of ALI or RILI, or for the alleviation of unremitting pulmonary leakage, which serves as a defining feature of the illness. A critical need exists for new mechanistic insights that can lead to novel strategies, biomarkers, and therapies to reduce lung injury. Sphingosine 1-phosphate (S1P) is a naturally occurring bioactive sphingolipid that acts extracellularly via its G protein-coupled S1P1-5 as well as intracellularly on various targets. S1P-mediated cellular responses are regulated by the synthesis of S1P, catalyzed by sphingosine kinases 1 and 2, and by the degradation of S1P mediated by lipid phosphate phosphatases, S1P phosphatases, and S1P lyase. We and others have demonstrated that S1P is a potent angiogenic factor that enhances lung endothelial cell integrity and an inhibitor of vascular permeability and alveolar flooding in preclinical animal models of ALI. In addition to S1P, S1P analogues such as 2-amino-2-(2-[4-octylphenyl]ethyl)-1,3-propanediol (FTY720), FTY720 phosphate, and FTY720 phosphonates offer therapeutic potential in murine models of lung injury. This translational review summarizes the roles of S1P, S1P analogues, S1P-metabolizing enzymes, and S1P receptors in the pathophysiology of lung injury, with particular emphasis on the development of potential novel biomarkers and S1P-based therapies for ALI and RILI.

FTY720 induces apoptosis in B16F10-NEX2 murine melanoma cells, limits metastatic development in vivo, and modulates the immune system

OBJECTIVE

Available chemotherapy presents poor control over the development of metastatic melanoma. FTY720 is a compound already approved by the Food and Drug Administration for the treatment of patients with multiple sclerosis. It has also been observed that FTY720 inhibits tumor growth in vivo (experimental models) and in vitro (animal and human tumor cells). The aim of this study was to evaluate the effects of FTY720 on a metastatic melanoma model and in tumor cell lines.

METHODS

We analyzed FTY720 efficacy in vivo in a syngeneic murine metastatic melanoma model, in which we injected tumor cells intravenously into C57BL/6 mice and then treated the mice orally with the compound for 7 days. We also treated mice and human tumor cell lines with FTY720 in vitro, and cell viability and death pathways were analyzed.

RESULTS

FTY720 treatment limited metastatic melanoma growth in vivo and promoted a dose-dependent decrease in the viability of murine and human tumor cells in vitro. Melanoma cells treated with FTY720 exhibited characteristics of programmed cell death, reactive oxygen species generation, and increased β-catenin expression. In addition, FTY720 treatment resulted in an immunomodulatory effect in vivo by decreasing the percentage of Foxp3+ cells, without interfering with CD8+ T cells or lymphocyte-producing interferon-gamma.

CONCLUSION

Further studies are needed using FTY720 as a monotherapy or in combined therapy, as different types of cancer cells would require a variety of signaling pathways to be extinguished.

Randomized, open-label study to evaluate patient-reported outcomes with fingolimod after changing from prior disease-modifying therapy for relapsing multiple sclerosis: EPOC study rationale and design

OBJECTIVE

The study to Evaluate Patient OutComes, Safety, and Tolerability of Fingolimod (EPOC; NCT01216072) aimed to test the hypothesis that therapy change to oral Gilenya (Novartis AG, Stein, Switzerland) (fingolimod) improves patient-reported outcomes compared with standard-of-care disease-modifying therapy (DMT) in patients with relapsing multiple sclerosis; safety and tolerability were also assessed. This communication describes the study rationale and design.

METHODS

EPOC is a phase 4, open-label, multi-center study conducted in the US and Canada of patients with relapsing forms of multiple sclerosis who are candidates for therapy change. Therapy change eligibility was determined by the treating physician (US patients) or required an inadequate response to or poor tolerance for at least 1 MS therapy (Canadian patients). Patients were randomly assigned in a 3:1 ratio to 6 months of treatment with once-daily oral fingolimod 0.5 mg or standard-of-care DMTs. The primary study end-point was the change from baseline in treatment satisfaction as determined by the global satisfaction sub-scale of the Treatment Satisfaction Questionnaire for Medication. Secondary end-points included changes from baseline in perceived effectiveness and side-effects, and measures of activities of daily living, fatigue, depression, and quality-of-life. A 3-month open-label fingolimod extension was available for patients randomly assigned to the DMT group who successfully completed all study visits.

RESULTS

Enrollment has been completed with 1053 patients; the patient population is generally older and has a longer duration of disease compared with populations from phase 3 studies of fingolimod.

LIMITATIONS

Inclusion criteria selected for patients with a sub-optimal experience with a previous DMT, limiting the collection of data on therapy change in patients who were satisfied with their previous DMT.

CONCLUSIONS

Results of the EPOC study are anticipated in early 2013 and will inform treatment selection by providing patient-centered data on therapy switch to fingolimod or standard-of-care DMTs.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01216072.

Consensus guidelines for the diagnosis and treatment of multiple sclerosis

The diagnosis of multiple sclerosis (MS) is dependent on the presence of clinical and paraclinical evidence demonstrating dissemination of central nervous system lesions in both space and time, as well as the exclusion of other disorders. Diagnostic criteria were originally promulgated in 1965 by the Schumacher committee and modified subsequently by the Poser committee to include paraclinical evidence. The most recent criteria are the 2010 modifications of the 2001 McDonald criteria, which are focused on making an earlier diagnosis of MS. This article provides guidelines, derived from clinical experience as well as evidence-based medicine, for the diagnosis and management of MS with special emphasis on practices in the Middle East.

Targeting cells in motion: migrating toward improved therapies

The development of clinical therapeutics that interfere with the migration of leukocytes has revolutionized the treatment of multiple sclerosis and holds great promise for the treatment of a wide range of inflammatory diseases. As the molecules essential for the multi-step adhesion cascade that mediates cellular migration have been elucidated, the number of potential targets available to modulate leukocyte trafficking has increased exponentially. In this Viewpoint, we briefly review our current understanding of these mole-cular targets and how these targets vary by tissue and leukocyte subset with emphasis on T cells. We then describe the two currently approved therapeutics that target cell migration, natalizumab and fingolimod, and discuss how an improved understanding of their function could pave the way for the development of safer and more efficacious therapies for inflammatory and autoimmune diseases.

Comparative effectiveness of early natalizumab treatment in JC virus-negative relapsing-remitting multiple sclerosis

OBJECTIVES

To estimate the long-term comparative effectiveness of first-line treatment in patients negative for anti-JC virus (JCV) antibodies with glatiramer acetate (GA), fingolimod, or natalizumab for relapsing-remitting multiple sclerosis (RRMS).

STUDY DESIGN

We developed a simulation model to estimate the average 20-year clinical risks and benefits of GA, fingolimod, and natalizumab for RRMS patients initially negative for anti-JCV antibodies.

METHODS

Model inputs included published natural history progressions of the Expanded Disability Status Scale (EDSS), treatment effects from randomized controlled trials on slowing disease progression and reducing relapse rates, risk of progressive multifocal leukoencephalopathy (PML), and utility preference scores. Outputs were long-term risks (PML risk and other non-PML risks), benefits (average relapse rate and time to disability [EDSS >7]), and quality-adjusted life years (QALYs).

RESULTS

Compared with GA, natalizumab resulted in 4.6 fewer relapses, 0.6 more years of disability free time, 0.0165 more cases of PML per treated patient, and an incremental 1.2 QALYs gained. Compared with fingolimod, natalizumab resulted in 1.7 fewer relapses, 0.1 more years of disability free time, 0.0165 more cases of PML per treated patient, and an incremental 0.4 QALYs gained. The probability that incremental QALYs favored natalizumab over GA was 0.963 and natalizumab over fingolimod was 0.720.

CONCLUSIONS

Average QALYs, a measure that aggregates across risks and benefits, favored natalizumab, suggesting more aggressive early intervention with natalizumab in the negative anti-JCV population. For certain decision makers, more evidence may be needed to further reduce the uncertainty in these comparative projections prior to making population-based adoption decisions.

Fingolimod (FTY720) in Severe Hepatic Impairment: Pharmacokinetics and Relationship to Markers of Liver Function

The authors assessed the impact of severe hepatic impairment on the disposition of fingolimod--a sphingosine-1-phosphate receptor immunomodulator primarily metabolized by CYP4F2--in 6 patients and 6 matched healthy controls who received a single 5-mg oral dose. Compared with healthy controls, severe hepatic-impaired subjects had a doubled area under the concentration time curve (AUC) and 50% prolonged elimination half-life but a similar peak blood concentration. When these data were combined with those from a previous study in mild and moderate hepatic-impaired subjects, there were significant positive correlations between fingolimod AUC versus bilirubin (r = 0.683) and prothrombin time (r = 0.777) and a significant negative correlation versus albumin (r = 0.578), confirming the importance of liver function for fingolimod clearance. For patients with severe hepatic impairment (Child-Pugh class C), a standard first dose of fingolimod could be given followed by a maintenance dose that is reduced by half from the normal maintenance dose.

Sphingosine-1-phosphate links persistent STAT3 activation, chronic intestinal inflammation, and development of colitis-associated cancer

Inflammatory bowel disease is an important risk factor for colorectal cancer. We show that sphingosine-1-phosphate (S1P) produced by upregulation of sphingosine kinase 1 (SphK1) links chronic intestinal inflammation to colitis-associated cancer (CAC) and both are exacerbated by deletion of Sphk2. S1P is essential for production of the multifunctional NF-κB-regulated cytokine IL-6, persistent activation of the transcription factor STAT3, and consequent upregulation of the S1P receptor, S1PR1. The prodrug FTY720 decreased SphK1 and S1PR1 expression and eliminated the NF-κB/IL-6/STAT3 amplification cascade and development of CAC, even in Sphk2(-/-) mice, and may be useful in treating colon cancer in individuals with ulcerative colitis. Thus, the SphK1/S1P/S1PR1 axis is at the nexus between NF-κB and STAT3 and connects chronic inflammation and CAC.