[Siponimod (BAF312): General Characteristics and Clinical Implications of Pharmacogenomic Dosage in the Treatment of Active Secondary Progressive Multiple Sclerosis]. / Siponimod (BAF312): Características generales e implicancias clínicas de la dosificación farmacogenómica en el tratamiento de la Esclerosis Múltiple secundaria progresiva.

Siponimod is a selective immunosuppressive medication, developed as the first oral therapy for active secondary progressive multiple sclerosis. This medication acts by modulating the sphingosine 1 phosphate (S1P) receptor, as an antagonist of S1P1 and S1P5, thus preventing the egress of lymphocytes from lymph nodes and preventing inflammatory processes in the Central Nervous System that trigger demyelination. There is extensive scientific knowledge regarding the administration of the medication to patients, which will depend on their pharmacogenetic characteristics. Therefore, the FDA strongly recommends conducting a genotyping study of the enzyme that metabolizes siponimod, CYP2C9, whose genetic variants *2 and *3 classify patients as poor, extensive, or rapid metabolizers. Siponimod is completely contraindicated for patients who are homozygous for CYP2C9*3. Additionally, before prescribing it, an electrocardiogram, assessments of antibody status, ophthalmic evaluation, varicella vaccination status, and peripheral lymphocyte count should be conducted, as the medication's effect is dose-dependent. Therefore, a titration process is carried out starting from 0.25mg up to 2 mg. The pharmacotherapeutic protocol of siponimod is a reliable reflection of the utility of pharmacogenetics in personalized medicine.

Absorption, Metabolism, and Excretion, In Vitro Pharmacology, and Clinical Pharmacokinetics of Ozanimod, a Novel Sphingosine 1-Phosphate Receptor Modulator.

Ozanimod is approved for the treatment of relapsing forms of multiple sclerosis. Absorption, metabolism, and excretion of ozanimod were investigated after a single oral dose of 1.0 mg [14C]ozanimod hydrochloride to six healthy subjects. In vitro experiments were conducted to understand the metabolic pathways and enzymes involved in the metabolism of ozanimod and its active metabolites. The total mean recovery of the administered radioactivity was ∼63%, with ∼26% and ∼37% recovered from urine and feces, respectively. Based on exposure, the major circulating components were active metabolite CC112273 and inactive metabolite RP101124, which together accounted for 50% of the circulating total radioactivity exposure, whereas ozanimod accounted for 6.7% of the total radioactive exposure. Ozanimod was extensively metabolized, with 14 metabolites identified, including two major active metabolites (CC112273 and CC1084037) and one major inactive metabolite (RP101124) in circulation. Ozanimod is metabolized by three primary pathways, including aldehyde dehydrogenase and alcohol dehydrogenase, cytochrome P450 isoforms 3A4 and 1A1, and reductive metabolism by gut microflora. The primary metabolite RP101075 is further metabolized to form major active metabolite CC112273 by monoamine oxidase B, which further undergoes reduction by carbonyl reductases to form CC1084037 or CYP2C8-mediated oxidation to form RP101509. CC1084037 is oxidized rapidly to form CC112273 by aldo-keto reductase 1C1/1C2 and/or 3ß- and 11ß-hydroxysteroid dehydrogenase, and this reversible oxidoreduction between two active metabolites favors CC112273. The ozanimod example illustrates the need for conducting timely radiolabeled human absorption, distribution, metabolism, and excretion studies for characterization of disproportionate metabolites and assessment of exposure coverage during drug development. SIGNIFICANCE STATEMENT: Absorption, metabolism, and excretion of ozanimod were characterized in humans, and the enzymes involved in complex metabolism were elucidated. Disproportionate metabolites were identified, and the activity of these metabolites was determined.

Evaluation of the effect of fingolimod (FTY720) on macular perfusion by swept-source optical coherence tomography angiography in patients with multiple sclerosis.

AIM: To determine changes in retinal microcirculation, caused by fingolimod (FTY720) use, via swept-source optical coherence tomography angiography (SS-OCTA) in relapsing-remitting multiple sclerosis (RR-MS) patients. MATERIALS AND METHODS: 80 patients with RR-MS, who were using fingolimod, and 50 healthy control subjects were included in the study. Group 1 consisted of 40 eyes from 40 RR-MS patients, who had been using fingolimod for less than six months, and Group 2 consisted of 40 eyes from 40 RR-MS patients, who had been using fingolimod for longer than six months. All participants underwent SS-OCTA via DRI OCT Triton (Topcon, Tokyo, Japan), analysing their central macular thickness (CMT) (µm), subfoveal choroidal thickness (SFCT) (µm), superficial (VDs) (%) and deep vascular plexuses (VDd) (%), choriocapillaris (VDcc) (%), and superficial and deep foveal avascular zones (FAZs, FAZd, respectively) (%) in mean values. RESULTS: The mean follow-up times for patients in Groups 1 and 2 were 2.9 ± 1.5 months and 22.5 ± 11.3 months, respectively. The FAZs value in Group 2 was found to be significantly higher than that in both Group 1 and the control group (p = 0.034, p = 0.042, respectively). The VDs central value in Group 2 did not differ significantly from that in Group 1 or the control group (p > 0.05), while the VDs central value was higher in Group 1 than in the control group (p = 0.008). In Group 1, the VDd central value was significantly higher than in Group 2 and the control group (p = 0.047; p = 0.020, respectively). The CMT measurement for Group 2 was significantly lower than in Group 1 and the control group (p = 0.008, p = 0.003, respectively). CONCLUSION: Fingolimod use seems to remarkably increase VDs and VDd measurements in the early period of administration and decrease CMT over a longer period of administration in patients with RR-MS.

Efficacy and safety of ozanimod in multiple sclerosis: Dose-blinded extension of a randomized phase II study.

BACKGROUND: Ozanimod, an oral immunomodulator, selectively targets sphingosine 1-phosphate receptors 1 and 5. OBJECTIVE: Evaluate efficacy, safety, and tolerability of ozanimod in relapsing multiple sclerosis. METHODS: In the RADIANCE Part A phase II study (NCT01628393), participants with relapsing multiple sclerosis were randomized (1:1:1) to once-daily ozanimod hydrochloride (0.5 or 1 mg) or placebo. After 24 weeks, participants could enter a 2-year, dose-blinded extension. Ozanimod-treated participants continued their assigned dose; placebo participants were re-randomized (1:1) to ozanimod hydrochloride 0.5 or 1 mg (equivalent to ozanimod 0.46 and 0.92 mg). RESULTS: A total of 223 (89.6%) of the 249 participants completed the blinded extension. At 2 years of the extension, the percentage of participants who were gadolinium-enhancing lesion-free ranged from 86.5% to 94.6%. Unadjusted annualized relapse rate during the blinded extension (week 24-end of treatment) was 0.32 for ozanimod hydrochloride 0.5 mg → ozanimod hydrochloride 0.5 mg, 0.18 for ozanimod hydrochloride 1 mg → ozanimod hydrochloride 1 mg, 0.30 for placebo → ozanimod hydrochloride 0.5 mg, and 0.18 for placebo → ozanimod hydrochloride 1 mg. No second-degree or higher atrioventricular block or serious opportunistic infection was reported. CONCLUSION: Ozanimod demonstrated sustained efficacy in participants continuing treatment up to 2 years and reached similar efficacy in participants who switched from placebo; no unexpected safety signals emerged.

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

A decrease in heart rate (HR) is a well-established first-dose effect of sphingosine-1-phosphate subtype 1 receptor (S1P1R) modulators. For compounds with a short half-life (t1/2), this can be mitigated by gradual up-titration to therapeutic doses, whereas this is not required for compounds with a long t1/2 due to the less pronounced first-dose-related negative chronotropic effects. Based on this conceptual framework, this mechanistic study investigated whether first-dose HR effects of ponesimod (t1/2 ~32 h) can be mitigated by prior administration of cenerimod (t1/2 ~415 h). Healthy subjects (n = 12) were randomly assigned to active or placebo (2:1 ratio). Active treatment consisted of a single dose of 10 mg ponesimod on Day 1, 18, and 37 and multiple-dose administration of 2 mg once daily cenerimod (Day 9-36). Placebos of cenerimod and ponesimod were used as reference treatment. Cardiodynamic parameters were derived from 24 h Holter electrocardiogram (ECG) assessments on Day 1, 9, 10, 18, 36, and 37. Ponesimod (10 mg) alone triggered a transient mean decrease from baseline in hourly mean HR of 17 bpm. In contrast, decreases of 5.0 and 4.8 bpm were observed when ponesimod was given at near half steady-state (Day 18) or steady-state (Day 37) cenerimod, respectively. Hourly mean HR decreased after first administration of cenerimod and placebo was 7.4 and 4.0 bpm, respectively. Treatment with ponesimod and cenerimod alone or in combination was safe and tolerated. First-dose-related negative chronotropic effects of ponesimod were less pronounced when administered after initiation of cenerimod suggesting mitigation of this class-related liability.

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

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

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

Background: Icanbelimod (formerly CBP-307) is a next-generation S1PR modulator, targeting S1PR1. In this first-in-human study, icanbelimod was investigated in healthy men in Australia. Methods: Participants were randomized 3:1, double-blind, to icanbelimod or placebo in four single-dose cohorts (0.1 mg, 0.25 mg, 0.5 mg [n=8 per cohort], 2.5 mg [n=4]) or for 28-days once-daily treatment in two cohorts (0.15 mg, 0.25 mg [n=8 per cohort]). Participants in the 0.25-mg cohort received 0.1 mg on Day 1. Treatments were administered orally after fasting; following one-week washout, icanbelimod was administered after breakfast in the 0.5-mg cohort. Results: Icanbelimod exposure increased rapidly and dose-dependently with single and multiple dosing (Tmax 4-7 hours). Lymphocyte counts decreased rapidly after single (-11%, 0.1 mg; -40%, 0.25 mg; -71%, 0.5 mg; -77%, 2.5 mg) and multiple doses (-49%, 0.15 mg; -75%, 0.25 mg), and recovered quickly, 7 days after dosing. After single-dose 0.5 mg, although a high-fat breakfast versus fasting did not affect maximal decrease, lymphocyte counts tended to be lower after breakfast across most timepoints up to 72 hours. Twenty-eight participants (63.6%) experienced mainly mild treatment-emergent adverse events (TEAEs). After single-dose icanbelimod, the most common TEAEs were headache (28.6%, n=6) and dizziness (19.0%, n=4). Three participants experienced transient bradycardia, with one serious, following single-dose 2.5 mg icanbelimod. After multiple-dose icanbelimod, the most common TEAEs were headache (50.0%, n=6) and lymphopenia (41.7%, n=5), and two participants withdrew due to non-serious TEAEs. Up-titration attenuated heart rate reductions. Conclusion: Icanbelimod was well-tolerated up to 0.5 mg and effectively reduced lymphocyte counts. Clinical trial registration: ClinicalTrials.gov, identifier NCT02280434.b.

Siponimod following Alemtuzumab in secondary progressive MS: investigating sequential therapy-A case series.

Alemtuzumab, a humanized anti-CD52 monoclonal antibody, is approved for treatment of highly active relapsing multiple sclerosis (MS) but requires vigilant post-treatment monitoring due to associated risks. The prescription of subsequent therapies following Alemtuzumab, as mandated by label guidance for a treatment-free period of at least 5 years, presents a complex challenge, particularly if there is concurrent conversion to secondary progressive disease course. We described a case-series of five patients starting therapy with Siponimod and followed up for 12 months period converted to secondary progressive MS previously exposed to Alemtuzumab. All patients received Siponimod 2 mg. Clinical evaluation measured with Expanded Disability Status Scale and cognitive evaluation measured with Brief International Cognitive Assessment for Multiple Sclerosis were stable after 12 months on therapy. No severe lymphopenia was recorded, nor serious adverse events. In conclusion, the long-term management of patients treated with Alemtuzumab transitioning to secondary progressive MS requires a proactive and multidisciplinary approach. By addressing the challenges associated with treatment limitations and short-term monitoring recommendations while considering alternative therapeutic options like Siponimod, clinicians can optimize outcomes and ensure continuity of care for individuals with MS.

Pharmacokinetics of S1P receptor modulators in the treatment of ulcerative colitis.

INTRODUCTION: Ulcerative colitis is a chronic inflammatory bowel disease, affecting the colorectal mucosae, with a relapsing-remitting course, characterized by the trafficking and gathering of lymphocytes in the inflammatory intestinal mucosa. Sphingosine-1-phosphate (S1P) receptor modulators preventing lymphocytes egress from lymphoid tissues to the active inflammation site is an alternative therapeutic option in this condition. AREA COVERED: We carried out a comprehensive review of the literature available on Medline, Scopus and Embase regarding the pharmacokinetics of S1P receptor modulators. For each compound, we reviewed the mechanism of action, pharmacokinetic data and efficacy and safety data from phase 3 studies and real-life studies when available. EXPERT OPINION: S1P receptor modulators, including ozanimod and etrasimod (both currently on the market) as well as VTX002 (under development), are a new class of drugs for the treatment of moderate to severe ulcerative colitis, inducing and maintaining the remission. Due to its pharmacokinetic features, this class of drugs has certain advantages such as an oral administration, a short half-life, a high volume of distribution, and no immunogenicity. On the other hand, there are risks of cardiological and ophthalmological side-effects, as well as drug-drug interactions risk, that require special attention from the healthcare providers.

Achievement of Clinical, Endoscopic, and Histological Outcomes in Patients with Ulcerative Colitis Treated with Etrasimod, and Association with Faecal Calprotectin and C-reactive Protein: Results From the Phase 2 OASIS Trial.

BACKGROUND AND AIMS: Etrasimod is an oral, once-daily, selective sphingosine 1-phosphate (S1P)1,4,5 receptor modulator for the treatment of moderately to severely active ulcerative colitis [UC]. This post-hoc analysis of the phase 2 OASIS trial [NCT02447302] evaluated its efficacy for endoscopic improvement-histologic remission [EIHR] and assessed correlation between faecal calprotectin [FCP] and C-reactive protein [CRP] levels with efficacy outcomes. METHODS: In total, 156 adults with moderately to severely active UC received once-daily etrasimod (1 mg [n = 52]; 2 mg [n = 50]) or placebo [n = 54] for 12 weeks. Clinical, endoscopic, and histologic variables were evaluated at baseline and Week 12. EIHR was defined as achievement of endoscopic improvement [endoscopic subscore ≤ 1, without friability] and histologic remission [Geboes score < 2.0]. Outcomes included the relationships between FCP and CRP concentration and clinical, endoscopic, and histologic variables. RESULTS: Achievement of EIHR was significantly higher in patients who received etrasimod 2 mg versus placebo [19.5% vs 4.1%; Mantel-Haenszel estimated difference, 15.4%; p = 0.010]. In the etrasimod 2 mg group, median FCP and CRP levels at Week 12 were significantly lower in patients who achieved clinical remission, endoscopic improvement, histologic remission, and EIHR versus patients who did not [all p < 0.05]. An FCP concentration cutoff of 250 µg/g achieved optimum sensitivity and specificity for efficacy, including EIHR [0.857 and 0.786, respectively; κ coefficient, 0.3584]. Higher proportions of patients with FCP ≤ 250 µg/g achieved efficacy outcomes at Week 12 versus patients with FCP > 250 µg/g. CONCLUSIONS: Etrasimod was effective for inducing EIHR in patients with UC. FCP and CRP may be useful, noninvasive biomarkers to monitor treatment response. CLINICALTRIALS.GOV NUMBER: NCT02447302.

An Overview of the Efficacy and Safety of Ozanimod for the Treatment of Relapsing Multiple Sclerosis.

Multiple sclerosis (MS) is a complex disease of the central nervous system that can cause permanent disability in young adults. A large armamentarium is available for its management and is increasing over time. Ozanimod is an oral drug belonging to the sphingosine-1-phosphate receptor (S1PR) modulator family recently approved in different countries for MS with active disease. It selectively modulates S1PR1 and S1PR5 to prevent autoreactive lymphocytes from entering the central nervous system (CNS), where they can determine inflammation and neurodegeneration. Ozanimod was tested in one Phase II and two Phase III pivotal trials and was shown to be effective and well tolerated. Moreover, further investigations, including comparative trials with other S1P modulators and MS disease-modifying drugs, are needed to better define placement in MS treatment. Furthermore, ozanimod is currently under evaluation for inflammatory bowel diseases, such as ulcerative colitis and Crohn's disease, in international phase III studies. This article retraces the itinerary leading to the approval of ozanimod for MS treatment and its peculiarities and potentiality inside the S1PR modulator family.

Concentration-QTc Modeling of Ozanimod's Major Active Metabolites in Adult Healthy Subjects.

Ozanimod, approved by regulatory agencies in multiple countries for the treatment of adults with relapsing multiple sclerosis, is a sphingosine 1-phosphate (S1P) receptor modulator, which binds with high affinity selectively to S1P receptor subtypes 1 and 5. The relationships between plasma concentrations of ozanimod and its major active metabolites, CC112273 and CC1084037, and the QTc interval (C-QTc) from a phase I multiple-dose study in healthy subjects were analyzed using nonlinear mixed effects modeling. QTc was modeled linearly as the sum of a sex-related fixed effect, baseline, and concentration-related random effects that incorporated interindividual and residual variability. Common linear, power, and maximum effect (Emax ) functions were assessed for characterizing the relationship of QTc with concentrations. Model goodness-of-fit and performance were evaluated by standard diagnostic tools, including a visual predictive check. The placebo-corrected change from baseline in QTc (ΔΔQTc) was estimated based on the developed C-QTc model using a nonparametric bootstrapping approach. QTc was better derived using a study-specific population formula (QTcP). Among the investigated functions, an Emax function most adequately described the relationship of QTcP with concentrations. Separate models for individual analytes characterized the C-QTcP relationship better than combined analytes models. Attributing QT prolongation independently to CC1084037 or CC112273, the upper bound of the 95% confidence interval of the predicted ΔΔQTcP was ~ 4 msec at the plateau of the Emax curves. Therefore, ΔΔQTcP is predicted to remain below 10 msec at the supratherapeutic concentrations of the major active metabolites.

Exosomes Derived from Nerve Stem Cells Loaded with FTY720 Promote the Recovery after Spinal Cord Injury in Rats by PTEN/AKT Signal Pathway.

BACKGROUND: Spinal cord injury (SCI) remains a challenge owing to limited therapies. The exosome of neural stem cells (NSCs-Exos) and FTY720 transplantation could improve SCI effectively. However, the effect and mechanism of NSCs-Exos combined with FTY720 (FTY720-NSCs-Exos) transplantation in the treatment of SCI are not fully understood. METHODS: Sprague Dawley rats (8-week-old) were used to establish the SCI model, followed by the treatment of NSCs-Exos, FTY720, and FTY720-NSCs-Exos. The effect of FTY720, NSCs-Exos, and FTY720-NSCs-Exos combination treatment on hindlimb function, pathological changes, apoptosis activity, and the expression of spinal edema-related proteins and apoptosis-related proteins in SCI models were investigated by BBB scoring, HE staining, TUNEL staining and immunohistochemistry, and Western blotting. Meanwhile, the effect of these treatments on spinal cord microvascular endothelial cells (SCMECs) was detected under hypoxic circumstance. RESULTS: Our results found that FTY720-NSCs-Exos could alleviate pathological alterations and ameliorate the hindlimb function and oxygen insufficiency in model mice after SCI. In addition, exosomes could ameliorate the morphology of neurons, reduce inflammatory infiltration and edema, decrease the expression of Bax and AQP-4, upregulate the expression of claudin-5 and Bcl-2, and inhibit cell apoptosis. At the same time, in vitro experiments showed that FTY720-NSCs-Exos could protect the barrier of SCMECs under hypoxic circumstance, and the mechanism is related to PTEN/AKT pathway. CONCLUSION: FTY720-NSCs-Exos therapy displayed a positive therapeutic effect on SCI by regulating PTEN/AKT pathway and offered a new therapy for SCI.

Regulatory roles of G-protein coupled receptors in adipose tissue metabolism and their therapeutic potential.

The high incidence of obesity has increased the need to discover new therapeutic targets to combat obesity and obesity-related metabolic diseases. Obesity is defined as an abnormal accumulation of adipose tissue, which is one of the major metabolic organs that regulate energy homeostasis. However, there are currently no approved anti-obesity therapeutics that directly target adipose tissue metabolism. With recent advances in the understanding of adipose tissue biology, molecular mechanisms involved in brown adipose tissue expansion and metabolic activation have been investigated as potential therapeutic targets to increase energy expenditure. This review focuses on G-protein coupled receptors (GPCRs) as they are the most successful class of druggable targets in human diseases and have an important role in regulating adipose tissue metabolism. We summarize recent findings on the major GPCR classes that regulate thermogenesis and mitochondrial metabolism in adipose tissue. Improved understanding of GPCR signaling pathways that regulate these processes could facilitate the development of novel pharmacological approaches to treat obesity and related metabolic disorders.

Siponimod: A Review in Secondary Progressive Multiple Sclerosis.

Oral siponimod (Mayzent®), a next-generation, selective sphingosine 1-phosphate receptor (S1PR) 1 and 5 modulator, is approved in several countries for the treatment of secondary progressive multiple sclerosis (SPMS), with specific indications varying between individual countries. In the pivotal EXPAND trial (median duration double-blind treatment 18 months) in a broad spectrum of patients with SPMS, once-daily oral siponimod 2 mg (initial dose titration over 6 days) was significantly more effective than placebo in reducing clinical and MRI-defined outcomes of disease activity and disability progression, including 3-month confirmed disability progression on the Expanded Disability Status Scale (EDSS), and was generally well tolerated in the core phase of the study. These beneficial effects of siponimod appeared to be sustained during up to 5 years of treatment in the ongoing open-label extension phase of EXPAND. The safety profile of siponimod is similar to that of other agents in its class, including adverse events of special interest (i.e. those known to be associated with S1PR modulators). No new safety signals were identified during up to 5 years' treatment in the open-label extension phase. Albeit further long-term efficacy and safety data from the real-world setting are required to fully define its role, given the paucity of current treatment options and its convenient dosage regimen, siponimod represents an important emerging option for the treatment of adult patients with SPMS with active disease evidenced by relapses or imaging-features of inflammatory activity.

Ozanimod: First Approval.

Ozanimod (ZEPOSIA®; Celgene Corporation) is a novel, orally administered sphingosine 1-phosphate (S1P) receptor modulator. In March 2020, the US FDA approved ozanimod capsules for use in the treatment of relapsing forms of multiple sclerosis, to include clinically isolated syndrome, relapsing-remitting disease, and active secondary progressive disease, in adults. In the same month, ozanimod received a positive CHMP opinion recommending approval in the EU for the treatment of adult patients with relapsing-remitting multiple sclerosis with active disease defined by clinical or imaging features. Ozanimod is currently being evaluated for use in ulcerative colitis and Crohn's disease in multinational phase III trials. This article summarizes the milestones in the development of ozanimod leading to its first approval for relapsing forms of multiple sclerosis.

Safety, Tolerability, Pharmacodynamics and Pharmacokinetics of Intravenous Siponimod: A Randomized, Open-label Study in Healthy Subjects.

PURPOSE: The goal of this study was to assess the safety, tolerability, pharmacodynamics (PD) and pharmacokinetics (PK) of intravenous (IV) siponimod in healthy subjects. METHODS: This randomized, open-label study was conducted in 2 parts. In Part 1, a total of 16 eligible subjects received either a single oral dose of siponimod (0.25 mg) followed by a single IV infusion (0.25 mg/3 h) in Sequence 1, or vice versa in Sequence 2. In Part 2, a total of 17 eligible subjects received single IV infusions of siponimod (1 mg/24 h). FINDINGS: No clinically relevant effect on mean 5-minute or hourly average heart rate was observed following the siponimod IV dosing regimens and both remained above 50 beats/min. Observed atrioventricular blocks and sinus pauses were asymptomatic. The mean change in absolute lymphocyte count from baseline was comparable for the siponimod 0.25 mg oral regimen and the two IV siponimod regimens. Oral siponimod displayed a good absolute bioavailability of 84%. The mean peak exposure of oral siponimod was approximately 48% lower than that of IV siponimod. The M17 metabolite was found to be the most prominent systemic metabolite of siponimod in humans. IMPLICATIONS: Siponimod IV infusions were well tolerated, with safety and PD (absolute lymphocyte count) profiles similar to those of oral siponimod. The PD/PK findings supported the development of an innovative rapid IV titration regimen for patients with intracerebral hemorrhage.

Ponesimod for the treatment of relapsing multiple sclerosis.

INTRODUCTION: Multiple Sclerosis (MS) is an immune-mediated, complex, chronic inflammatory, and neurodegenerative disease of the central nervous system. Among the several therapeutic options developed over the last decade for relapsing MS (RMS), fingolimod, a sphingosine 1-phosphate receptor (S1PR) modulator, was the first oral treatment. The adverse events associated with fingolimod have limited its use in certain populations, thus further stimulating the search for other S1PR modulators. AREAS COVERED: The authors reviewed the English-published literature on ponesimod using the PubMed database. The search terms used were 'ponesimod' or 'ACT-128,800' and 'multiple sclerosis.' Available data on the pharmacological profile of ponesimod and the information on clinical efficacy and safety drawn from clinical trials in comparison with other S1PR modulators are presented and discussed. EXPERT OPINION: Published peer-reviewed data on long-term safety and efficacy are still lacking but have been collected and regulatory authorities expressed a favorable opinion to market access. At present, we believe that ponesimod has little chance of becoming a leading treatment for RMS due to the availability of many alternative options and the timing of market access. Given its favorable risk-benefit and convenience profile, however, ponesimod might become a leading option among S1P receptor modulators used for RMS.

Effect of the sphingosine-1-phosphate receptor modulator ozanimod on leukocyte subtypes in relapsing MS.

OBJECTIVE: To better understand ozanimod's mechanism of action (MOA), we conducted exploratory analyses from a phase 1 study to characterize ozanimod's effect on circulating leukocyte subsets in patients with relapsing multiple sclerosis. METHODS: An open-label pharmacodynamic study randomized patients to oral ozanimod hydrochloride (HCl) 0.5 (n = 13) or 1 mg/d (n = 11) for ∼12 weeks (including 7-day dose escalation). Circulating leukocyte subsets were quantified using flow cytometry (days 28, 56, and 85) and epigenetic cell counting (days 2, 5, 28, 56, and 85) and compared with baseline (day 1) using descriptive statistics. RESULTS: Ozanimod caused dose-dependent reductions in absolute lymphocyte counts. Observed by both methodologies, circulating CD19+ B- and CD3+ T-cell counts were reduced by >50% with ozanimod HCl 0.5 mg and >75% with 1 mg at day 85. Based on flow cytometry, ozanimod HCl 1 mg showed greater decreases in CD4+ than CD8+ T cells, greater decreases in both CD4+ and CD8+ central memory vs effector memory T cells, and reductions in mean CD4+ and CD8+ naive T cells by ≥90% at day 85. In the flow cytometry analysis, changes in monocytes, natural killer, and natural killer T cells were minimal. Using epigenetic cell counting, greater reductions for Th17 than T regulatory cells were determined. CONCLUSION: Ozanimod induced dose-dependent reductions in circulating B- and T-cell counts and differential effects on naive and memory CD4+ and CD8+ T cells and CD19+ B cells. Data characterized with both a novel epigenetic cell-counting method and flow cytometry support ozanimod's MOA. CLINICAL TRIAL REGISTRATION: clinicaltrials.gov NCT02797015.

FTY720 Attenuates Neuropathic Pain after Spinal Cord Injury by Decreasing Systemic and Local Inflammation in a Rat Spinal Cord Compression Model.

Neuropathic pain severely impairs rehabilitation and quality of life after spinal cord injury (SCI). The sphingosine-1-phosphate receptor agonist, FTY720, plays an important protective role in neuronal injury. This study aims to examine the effects of FTY720 in a rat acute SCI model, focusing on neuropathic pain. Female rats with SCI induced by 1-min clip compression were administered vehicle or 1.5 mg/kg of FTY720 24 h after the injury. Using the mechanical nociceptive threshold test, we monitored neuropathic pain and performed histological analysis of the pain pathway, including the µ opioid receptor (MOR), hydroxytryptamine transporter (HTT), and calcitonin gene-related peptide (CGRP). Motor score, SCI lesion volume, residual motor axons, inflammatory response, glial scar, and microvascular endothelial dysfunction were also compared between the two groups. FTY720 treatment resulted in significant attenuation of post-traumatic neuropathic pain. It also decreased systemic and local inflammation, thereby reducing the damaged areas and astrogliosis and resulting in motor functional recovery. Whereas there was no difference in the CGRP expression between the two groups, FTY720 significantly preserved the MOR in both the caudal and rostral areas of the spinal dorsal horn. Whereas HTT was preserved in the FTY720 group, it was significantly increased in the rostral side and decreased in the caudal side of the injury in the vehicle group. These results suggest that FTY720 ameliorates post-traumatic allodynia through regulation of neuroinflammation, maintenance of the blood-brain barrier, and inhibition of glial scar formation, thereby preserving the connectivity of the descending inhibitory pathway and reducing neuropathic pain.