Selective Sphingosine 1-phosphate Receptor Modulator Research Articles

P524 Etrasimod shows low risk of adverse events following concomitant use with opioids or antidepressants in patients with ulcerative colitis

Abstract Background Etrasimod is an oral, once-daily (QD), selective sphingosine 1-phosphate (S1P)1,4,5 receptor modulator for the treatment of moderately to severely active ulcerative colitis (UC). Unlike the other S1P receptor modulator approved for UC, etrasimod and its metabolites do not have a molecular structure to inhibit monoamine oxidase (MAO).1 Coadministration of drugs that inhibit MAO with opioids and antidepressants may increase the risk of adverse events (AEs), including hypertension.2 This post hoc analysis evaluated the incidence of AEs potentially related to serotonin syndrome in patients taking etrasimod and concomitant opioids or antidepressants in the phase 3 ELEVATE UC 52 (NCT03945188) and ELEVATE UC 12 (NCT03996369) trials. Methods Safety data pooled from both trials were analysed in patients receiving etrasimod 2 mg QD (up to 52 weeks of exposure) with/without concomitant opioids or antidepressants. We report the proportions of patients who had ≥1 concurrent AE potentially related to serotonin syndrome, consisting of one standardised MedDRA Query, one query based on the Hunter Criteria and supplemental preferred terms (pyrexia, tachycardia and hypertension-related AEs).3 Results Among 527 patients receiving etrasimod, 77 (14.6%) and 35 (6.6%) patients were taking concomitant opioids or antidepressants, respectively. Most patients on concomitant opioids or antidepressants were White (80.0–88.3%); male (50.6–51.4%); their median age was 35.0 (18.0–70.0) and 41.0 (19.0–74.0) years, respectively. More patients with vs without concomitant opioids or antidepressants, respectively, consumed alcohol (40.3% vs 24.7% and 48.6% vs 25.4%) and used tobacco (40.3% vs 20.9% and 34.3% vs 23.0%). The incidence of other AEs potentially related to serotonin syndrome was low and generally comparable in all subgroups; reported rates of pyrexia and tachycardia were similar in patients with/without concomitant opioids or antidepressants (Table). Hypertension-related AEs were infrequent and generally balanced. No AEs per the Hunter Criteria were reported in patients on concomitant opioids or antidepressants (Table). No reported AEs were serious or led to treatment discontinuation among patients taking these concomitant medications. Conclusion The incidence of AEs was low and comparable in patients receiving etrasimod with or without concomitant opioids or antidepressants. This analysis supports the low likelihood of clinically relevant drug–drug interactions between etrasimod and medications commonly prescribed to patients with UC, such as opioids or antidepressants.

S455 Efficacy and Safety of the Selective Sphingosine 1-Phosphate Receptor Modulator, Etrasimod, in Adult Patients With Eosinophilic Esophagitis: Primary Results From the Phase 2 VOYAGE Study

S455 Efficacy and Safety of the Selective Sphingosine 1-Phosphate Receptor Modulator, Etrasimod, in Adult Patients With Eosinophilic Esophagitis: Primary Results From the Phase 2 VOYAGE Study

PHARMACOKINETIC AND PHARMACODYNAMIC ANALYSIS OF AMISELIMOD, A SELECTIVE SPHINGOSINE 1-PHOSPHATE RECEPTOR MODULATOR, IN HEALTHY SUBJECTS: RESULTS FROM A PHASE 1 STUDY

Amiselimod is a selective sphingosine 1-phosphate receptor modulator in development for inflammatory bowel disease. It is converted to its active metabolite, amiselimod phosphate (amiselimod-P), and has a long half-life and slow accumulation to steady state. We evaluated a multiple-dose titration regimen to determine the plasma pharmacokinetic (PK) profile of amiselimod and amiselimod-P at steady state for the 0.4 mg QD therapeutic dose on day 13 and for the 0.8 mg QD supratherapeutic dose on day 26. We also investigated the pharmacodynamic (PD) effect of amiselimod on absolute lymphocyte counts (ALCs).

PHARMACOKINETIC AND PHARMACODYNAMIC ANALYSIS OF AMISELIMOD, A SELECTIVE SPHINGOSINE 1-PHOSPHATE RECEPTOR MODULATOR, IN HEALTHY SUBJECTS: RESULTS FROM A PHASE 1 STUDY

Abstract BACKGROUND Amiselimod is a selective sphingosine 1-phosphate receptor modulator in development for inflammatory bowel disease. It is converted to its active metabolite, amiselimod phosphate (amiselimod-P), and has a long half-life and slow accumulation to steady state. We evaluated a multiple-dose titration regimen to determine the plasma pharmacokinetic (PK) profile of amiselimod and amiselimod-P at steady state for the 0.4 mg QD therapeutic dose on day 13 and for the 0.8 mg QD supratherapeutic dose on day 26. We also investigated the pharmacodynamic (PD) effect of amiselimod on absolute lymphocyte counts (ALCs). METHODS A randomized, double-blind, multiple-dose, placebo-controlled, parallel study with a nested crossover design assessed amiselimod and amiselimod-P. Healthy adults received a single dose of placebo followed by oral amiselimod, which was upwardly titrated in doses ranging from 0.4 to 1.6 mg QD to rapidly achieve steady-state concentrations for the 0.4 mg QD and 0.8 mg QD doses within a 28-day treatment period. The PK parameters of amiselimod and amiselimod-P (on days 1, 13 and 26) included the geometric mean (geometric coefficient of variation percentage [CV%]) maximum plasma concentration (Cmax), median (minimum, maximum) time to Cmax (Tmax), geometric mean (geometric CV%) area under the concentration-time curve (AUC) from time 0 to the last measurable concentration, and geometric mean (geometric CV%) AUC from time 0 to 23.5 hours postdose (AUC0-23.5). Multidose PD were evaluated by changes in ALCs. RESULTS The PK population included 95 amiselimod-treated participants and the PD population included 190 participants who received amiselimod or placebo. On day 13, the steady-state AUC and Cmax for amiselimod 0.4 mg QD increased by 10-fold for amiselimod and by 4-fold for amiselimod-P compared with day 1. On day 26, the steady-state AUC0-23.5 and Cmax for amiselimod 0.8 mg QD increased by 1.9-fold for amiselimod and by 1.8-fold for amiselimod-P compared with day 13. The median Tmax of plasma amiselimod and amiselimod-P were similar on all 3 days and were reached at 11 to 12 hours postdose for amiselimod and at 10 hours postdose for amiselimod-P. The mean ALCs for amiselimod exhibited a gradual decrease from predose (1.681 × 103/uL) to a nadir of 0.424 × 103/uL on day 27. CONCLUSIONS The abbreviated amiselimod dosing titration regimen reached steady state within 14 days for the therapeutic 0.4 mg QD regimen and within 26 days for the supratherapeutic 0.8 mg QD regimen; expected decreases in ALCs were observed following amiselimod.

Ponesimod: An Oral Second-Generation Selective Sphingosine 1-Phosphate Receptor Modulator for the Treatment of Multiple Sclerosis.

To describe the safety, efficacy, and potential role in therapy of ponesimod, which was recently approved by the Food and Drug Administration (FDA) as a therapeutic option for the treatment of multiple sclerosis (MS). A PubMed literature search using the following terms: ponesimod and MS (January 1, 2012-October 31, 2022). FDA product labeling was also reviewed for pertinent data sources. All relevant English-language articles examining efficacy and/or safety of ponesimod were considered for inclusion. Ponesimod is an orally administered second-generation sphingosine 1-phospate (S1-P) receptor modulator classified as a disease modifying treatment (DMT) for MS. Clinical studies have shown that ponesimod prevents relapse in patients with relapsing-remitting MS (RRMS) and has superior efficacy compared with teriflunomide. Nasopharyngitis, upper respiratory tract infections, headache, high blood pressure, and liver dysfunction were some of the common adverse effects associated with ponesimod. Dyspnea, bradyarrhythmias, atrioventricular conduction delays, and macular edema were some of the rare but serious adverse effects associated with ponesimod. Some advantages of ponesimod over other S1-P receptor modulators approved for RRMS include selectivity for the S1-P1 receptor and short half-life, which allows for quick reversal of immunosuppressive effects. However, data from long-term efficacy and safety studies and more direct comparison studies with other DMTs are required. Currently available data suggest that ponesimod is a useful addition to other high-efficacy DMTs available to treat patients with MS.

Ozanimod-Dependent Activation of SIRT3/NF-κB/AIM2 Pathway Attenuates Secondary Injury After Intracerebral Hemorrhage.

Intracerebral hemorrhage (ICH) is characterized by poor prognosis and high mortality rates. To date, satisfactory therapeutic approaches for ICH remain limited, so it is urgently needed to develop a safer and more effective prescription. Secondary inflammatory response has been acknowledged as an aggravating factor to neurological deterioration after ICH. As a component of inflammasome sensors, absent in melanoma 2 (AIM2) plays an important role in the neuroinflammation process. Here, ozanimod, a novel selective sphingosine 1-phosphate receptor modulator, has gained much attention, which alleviates the resultant neuroinflammation and improves functional recovery derived from ICH. In this study, ozanimod improved neurological functions of ICH mice via reduction of hematoma size. Furthermore, both microglial and AIM2 inflammasome activations were reversed by ozanimod, which are confirmed by the downregulation of related inflammatory proteins and cytokines (IL-1β, IL-6, and TNF-α), coupled with the upregulation of SIRT3, by leveraging the Western blot and enzyme-linked immunosorbent assay. Additionally, we find that ozanimod decreases nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) expression. Notably, in vitro cell experiments induced by lipopolysaccharide confirms that the anti-inflammatory effect of ozanimod could be abolished by the SIRT3 inhibitor. In conclusion, these results indicate that ozanimod mitigates ICH-induced secondary inflammatory responses by modulating AIM2 inflammasome mediated by SIRT3/NF-κB/AIM2 pathway. This demonstrates ozanimod orchestrates ICH-induced neuroinflammation and could be a targeted therapy for improving prognosis of ICH.

043 Efficacy of siponimod in secondary progressive multiple sclerosis with active disease: EXPAND study subgroup analysis

BackgroundSiponimod, a selective sphingosine 1-phosphate receptor modulator, demonstrated clini- cally relevant effects in a typical secondary progressive multiple sclerosis (SPMS) population in the Phase 3 EXPAND study, with 21% and 26% reductions in 3- and 6-month confirmed disability progression (CDP) versus placebo.MethodsPost hoc subgroup analysis was performed in patients with active disease (defined as the presence of relapses in 2 years before screening and/or ≥1 T1 gadolinium-enhancing [Gd ] lesion at baseline) to assess the efficacy of siponimod 2mg versus placebo in this population.ResultsThis analysis included 779 SPMS patients with active disease (siponimod [n=516], placebo [n=263]). The proportion of patients with relapse in the 2 years prior to study was 76% and with Gd lesions at baseline 45%. Siponimod significantly reduced 3-month CDP risk by 31% (HR [95% CI]: 0.69 [0.53, 0.91]; p=0.0094) and 6-month CDP risk by 37% (HR [95% CI]: 0.63 [0.47, 0.86], p=0.0040) versus placebo. Reductions in risk of 6 month SDMT worsening, ARR, and MRI endpoints were also seen.ConclusionsIn this subgroup of active SPMS patients from EXPAND, benefits on disability progression were more pronounced with clinically relevant effects across disability progression, cognitive processing speed, and MRI inflammatory disease activity.g.giovannoni@qmul.ac.uk

P562 A Phase 1 Study Evaluating the Effect of Coadministration of Etrasimod on the Pharmacokinetics and Pharmacodynamics of a Monophasic Oral Contraceptive in Healthy Female Volunteers

Abstract Background Etrasimod (ETR) is a once-daily (QD), oral, selective sphingosine 1-phosphate receptor modulator in clinical development for immune-mediated inflammatory disorders including inflammatory bowel disease (IBD) and atopic dermatitis. At diagnosis, ~50% of patients with IBD are <35 years old. Oral contraceptives (OC) are the most common birth control among women in the US. It’s important to ensure an IBD therapy does not impact the pharmacokinetic (PK)/pharmacodynamic (PD) performance of the OC. This study evaluated the effect of coadministration of ETR on the PK/PD performance of a monophasic OC. Methods This open-label Phase 1 study enrolled 21 premenopausal healthy female adults (18–40 years). On Days 1–21 of Period 1 (Days 1–28), participants received OC containing 30mcg ethinylestradiol (EE) and 50mcg levonorgestrel (LVG). On Day 23, participants initiated ETR 2mg QD such that steady-state concentrations were achieved by Day 28 and thereafter. On Days 29–49 of Period 2 (Days 29–50), the OC was coadministered with ETR 2mg QD. Samples for measuring the pharmacologically active components of the OC (EE and LVG) were collected over 24 hours on Days 21 and 49. Log-transformed primary PK parameters were calculated and compared using analysis of variance with treatment as fixed effect and participant as random effect. PD markers (follicle-stimulating hormone [FSH], luteinizing hormone [LH], estradiol, progesterone) were measured at baseline (Days 1 and 29) and throughout Periods 1 and 2. Largest ovarian follicle size measured by transvaginal ultrasound (TVUS), sex hormone–binding globulin (SHBG) levels, and Hoogland score were measured on Days 1 (before OC dosing), 11, 29 (before OC+ETR dosing), and 39. Safety and tolerability were also evaluated. Results Only minor-to-mild increases in EE and LVG Cmax,ss and AUCtau,ss exposure measures were observed when the OC was coadministered with ETR vs when the OC was administered alone (Table). These changes were not considered clinically relevant. Markers of ovarian activity (FSH, LH, estradiol, progesterone, SHBG, TVUS/Hoogland score) demonstrated no clinically relevant impact of coadministration of ETR on the PD performance of the OC. All treatments were generally well tolerated. Most treatment-emergent adverse events (AEs) were mild or moderate; 2 participants had severe AEs. No abnormalities in laboratory parameters, vital signs, or 12-lead electrocardiogram assessments were noted. Conclusion The PK/PD performance of the monophasic OC was not altered to a clinically relevant extent; thus contraceptive efficacy was maintained during coadministration with ETR. ETR and the monophasic OC, administered alone or in combination, were generally well tolerated.

OP27 A Phase 1 Study Evaluating the Bioequivalence of the Proposed Commercial and Clinical Formulations of Etrasimod 2mg, and the Effect of Food on the Pharmacokinetics of the Proposed Commercial Formulation in Healthy Volunteers

Abstract Background Etrasimod (ETR) is a once-daily, oral, selective sphingosine 1-phosphate receptor modulator in clinical development for immune-mediated inflammatory disorders including ulcerative colitis, Crohn’s disease, eosinophilic esophagitis, and atopic dermatitis. This study evaluated the single-dose bioequivalence of the proposed commercial and clinical formulations of ETR 2mg in the fasted state, and the effect of food on the pharmacokinetics of the proposed commercial formulation. Methods This 3-treatment, 3-period crossover Phase 1 study enrolled 18 healthy adults (18–55 years: 10 males/8 females). Participants were randomized to 6 treatment sequences (3 participants/sequence: ABC, BCA, CAB, ACB, BAC, CBA) consisting of Treatment A (single-dose ETR 2mg clinical formulation, fasted), Treatment B (single-dose ETR 2mg proposed commercial formulation, fasted), and Treatment C (single-dose ETR 2mg proposed commercial formulation, fed). Treatments were administered on Days 1, 10, and 19 to allow 8-day washout periods between treatments. In the fed state (Treatment C), all participants received an FDA-standard high-fat, high-calorie meal. Blood samples for determination of ETR concentration were collected at prespecified timepoints to 168 hours post dose. Analysis of variance was performed on log-transformed Cmax, AUC0-last, and AUC0-∞ values to determine geometric least squares mean ratios (GLSMR) of Test/Reference and associated 90% confidence intervals (CI) to assess bioequivalence and food effects. Safety and tolerability of ETR were also evaluated. Results Bioequivalence: The 90% CI for the GLSMR of ETR Cmax and AUC plasma exposure measures, comparing the proposed commercial vs clinical formulations, were within the accepted 80%–125% range (GLSMR and 90% CI) for establishing bioequivalence (Table 1). Median Tmax for Treatments A and B were both 4 hours. Food Effect: The 90% CI for the GLSMR of ETR Cmax and AUC plasma exposure measures, comparing the proposed commercial formulation under fed vs fasted conditions, were within the accepted 80%–125% range for establishing no food effect (Table 2). Median Tmax for Treatment C was 6 hours. Safety and Tolerability: All treatment-emergent adverse events (AEs) were mild (except 1 moderate AE [headache]). One participant had an AE leading to study drug discontinuation. There were no serious AEs or deaths. Conclusion Based on results from this study, the proposed commercial and clinical formulations of ETR 2mg were bioequivalent in terms of rate and extent of absorption. No significant differences were demonstrated in ETR exposure for the proposed commercial formulation under fed and fasted conditions. All treatments were generally safe and well tolerated.

Review article: the sphingosine 1 phosphate/sphingosine 1 phosphate receptor axis - a unique therapeutic target in inflammatory bowel disease.

Ozanimod, a high selective sphingosine 1 phosphate (S1P) receptor (S1PR) 1/5 modulator was approved by the Food and Drug Administration for the treatment of adult patients with moderately to severely active ulcerative colitis. Additional S1PR modulators are being tested in clinical development programmes for both ulcerative colitis and Crohn's disease. To provide an overview of advances in understanding S1PRs biology and summarise preclinical and clinical investigations of S1P receptor modulators in chronic inflammatory disease with special emphasis on inflammatory bowel diseases (IBD). We performed a narrative review using PubMed and ClinicalTrials.gov. Through S1PRs, S1P regulates multiple cellular processes, including proliferation, migration, survival, and vascular barrier integrity. The S1PRs function of regulating lymphocyte trafficking is well known, but new functions of S1PRs expand our knowledge of S1PRs biology. Several S1PR modulators are in clinical development for both ulcerative colitis and Crohn's disease and have shown promise in phase II and III studies with ozanimod now being approved for ulcerative colitis. S1P receptor modulators constitute a novel, promising, safe, and convenient strategy for the treatment of IBD.

Pfizer to acquire biotech firm Arena for $6.7 billion

Seeking to add firepower to its efforts to develop autoimmune disease drugs, Pfizer will acquire Arena Pharmaceuticals for about $6.7 billion. Arena’s portfolio includes several development-stage drug candidates, including lead candidate etrasimod, an oral, selective sphingosine 1-phosphate receptor modulator currently in Phase 3 clinical trials for ulcerative colitis and a Phase 2/3 trial for Crohn’s disease. Analysts say the deal will boost Pfizer’s pipeline in inflammation and immunology drugs and diversify the firm beyond Janus kinase inhibitors, inflammation drugs that have come under increasing scrutiny. The US Food and Drug Administration requires new heart safety and cancer warnings for several drugs in the category, including one from Pfizer. Pfizer’s agreement to pay $100 per share for Arena, double its previous closing price, is reasonable, especially given prospects for etrasimod, according to a note from stock analysts at Mizuho Securities. The price premium is mitigated by Pfizer’s profits from the COVID-19

P029 Pharmacokinetic/Pharmacodynamic Analysis of Amiselimod, a Selective Sphingosine 1-Phosphate Receptor Modulator, in Healthy Subjects: Results From a Phase 1 Study.

Amiselimod is a selective sphingosine 1-phosphate receptor modulator in development for inflammatory bowel disease. It is converted to its active metabolite, amiselimod phosphate (amiselimod-P), and has a long half-life and slow accumulation to steady state. We evaluated a multiple-dose titration regimen to determine the plasma pharmacokinetic (PK) profile of amiselimod and amiselimod-P at steady state for the 0.4 mg QD therapeutic dose on day 13 and for the 0.8 mg QD supratherapeutic dose on day 26. We also investigated the pharmacodynamic (PD) effect of amiselimod on absolute lymphocyte counts (ALCs). A randomized, double-blind, multiple-dose, placebo-controlled, parallel study with a nested crossover design assessed amiselimod and amiselimod-P. Healthy adults received a single dose of placebo followed by oral amiselimod, which was upwardly titrated in doses ranging from 0.4 to 1.6 mg QD to rapidly achieve steady-state concentrations for the 0.4 mg QD and 0.8 mg QD doses within a 28-day treatment period. The PK parameters of amiselimod and amiselimod-P (on days 1, 13 and 26) included the geometric mean (geometric coefficient of variation percentage [CV%]) maximum plasma concentration (Cmax), median (minimum, maximum) time to Cmax (Tmax), geometric mean (geometric CV%) area under the concentration-time curve (AUC) from time 0 to the last measurable concentration, and geometric mean (geometric CV%) AUC from time 0 to 23.5 hours post dose (AUC0-23.5). Multidose PD were evaluated by changes in ALCs. The PK population included 95 amiselimod-treated participants and the PD population included 190 participants who received amiselimod or placebo. On day 13, the steady-state AUC and Cmax for amiselimod 0.4 mg QD increased by 10-fold for amiselimod and by 4-fold for amiselimod-P compared with day 1. On day 26, the steady-state AUC0-23.5 and Cmax for amiselimod 0.8 mg QD increased by 1.9-fold for amiselimod and by 1.8-fold for amiselimod-P compared with day 13. The median Tmax of plasma amiselimod and amiselimod-P were similar on all 3 days and were reached at 11 to 12 hours post dose for amiselimod and at 10 hours post dose for amiselimod-P. The mean ALCs for amiselimod exhibited a gradual decrease from pre-dose (1.681 × 103/uL) to a nadir of 0.424 × 103/uL on day 27. The abbreviated amiselimod dosing titration regimen reached steady state within 14 days for the therapeutic 0.4 mg QD regimen and within 26 days for the supratherapeutic 0.8 mg QD regimen; expected decreases in ALCs were observed following amiselimod.

P291 Pharmacokinetics, safety, and tolerability of etrasimod (APD334) in subjects with mild, moderate, or severe hepatic impairment: a single-dose, open-label, parallel-group study

Abstract Background Etrasimod is an oral, selective sphingosine 1-phosphate receptor modulator in clinical development for immune-mediated inflammatory disorders, including ulcerative colitis, Crohn’s disease, and eosinophilic esophagitis. The objective of this study was to evaluate the effect of hepatic impairment on the pharmacokinetics (PK), safety, and tolerability of etrasimod. Methods This single-dose, open-label, parallel-group study included 36 adult subjects (aged 18-80 years; body mass index ≥18 kg/m2) with hepatic impairment, based on Child-Pugh score at screening (mild=5 to 6 [n=8], moderate=7 to 9 [n=8], severe=10 to 14 [n=6]), and their demographically matched control subjects with normal hepatic function (n=14 total). The first subject with severe hepatic impairment was enrolled after ≥2 subjects with mild and ≥2 subjects with moderate hepatic impairment had been enrolled and followed for ≥48 hours after dosing to ensure no observed significant safety signals. On Day 1, subjects received a single oral dose of etrasimod 2 mg after a ≥10 hour fast. PK and safety data were collected over a 21-day follow-up period. Results Thirty-six subjects were enrolled and dosed; 35 subjects completed the study. When compared with their respective demographically matched normal control groups, single dose etrasimod peak exposure (Cmax) was comparable for all hepatic impairment groups, whereas etrasimod total exposure (AUC) measures were progressively higher (up to 57.3% higher) in the mild, moderate, and severe hepatic impairment groups (Table 1). Unbound etrasimod Cmax values were progressively lower (up to 42.0% lower) in the mild, moderate, and severe hepatic impairment groups, whereas unbound etrasimod AUC values were typically comparable for all hepatic impairment groups, when compared with their respective demographically matched normal control groups (Table 2). Etrasimod t1/2 only moderately increased as hepatic function decreased, with mean values ranging from 43.9 to 59.5 hours in the demographically matched normal control groups and mean values of 55.7, 69.7, and 76.5 hours in the mild, moderate, and severe hepatic impairment groups, respectively. A single oral dose of etrasimod 2 mg was well tolerated; there were no clinically significant safety findings when administered to subjects with normal hepatic function or subjects with mild, moderate, or severe hepatic impairment. Conclusion A single oral dose of etrasimod 2 mg was well tolerated, with relatively modest changes in etrasimod exposure observed in subjects with mild, moderate, or severe hepatic impairment. These results suggest that etrasimod dose adjustment may not be warranted in subjects with hepatic impairment.

SAFETY OF AMISELIMOD IN HEALTHY SUBJECTS: RESULTS FROM A PHASE 1 RANDOMIZED, DOUBLE-BLIND, PLACEBO-CONTROLLED STUDY

To evaluate the safety profile of amiselimod, a selective sphingosine 1-phosphate receptor modulator which has been shown to regulate lymphocyte trafficking and is in development for the treatment of inflammatory bowel disease.

SAFETY OF AMISELIMOD IN HEALTHY SUBJECTS: RESULTS FROM A PHASE 1 RANDOMIZED, DOUBLE-BLIND, PLACEBO-CONTROLLED STUDY

Abstract Objective To evaluate the safety profile of amiselimod, a selective sphingosine 1-phosphate receptor modulator which has been shown to regulate lymphocyte trafficking and is in development for the treatment of inflammatory bowel disease. Methods A randomized, double-blind, multiple-dose, placebo-controlled, parallel study with a nested crossover design evaluated the safety and tolerability profile of amiselimod. Healthy adults were randomized in a 2:1:1 ratio during a 28-day treatment period accordingly: a single dose of placebo followed by oral amiselimod (upwardly titrated in doses ranging from 0.4 to 1.6 mg to achieve 0.4 mg and 0.8 mg steady-state exposure; a single dose of oral moxifloxacin 400 mg followed by placebo; or placebo followed by a single dose of moxifloxacin 400 mg. The safety population included all subjects who received at least one dose of treatment. Adverse events (AE) and serious AEs were collected. Treatment-emergent AEs were defined as an AE that was starting or worsening at the time of or after study drug administration. Changes in clinical laboratory parameters (including lymphocyte counts), physical examinations, vital signs, and electrocardiogram parameters (including heart rate, PR, QRS, and QT intervals) were recorded. Subjects were permitted to withdraw if lymphocyte counts were ≤ 0.2 x 109/L. Results The safety population included 190 subjects of which 95 received amiselimod and 95 were in the combined moxifloxacin group. Subjects were 40% female, 83% white, and the mean (standard deviation) age was 39.0 (8.8) years. The discontinuation rate was 8% (n=8) in the amiselimod group and 4% (n=4) in the moxifloxacin group. Three subjects who received amiselimod discontinued because they met the stopping criteria for low lymphocyte counts. One subject experienced an amiselimod-related serious AE of atrial fibrillation on day 26 (after receiving amiselimod 1.6 mg for 3 of the preceding 4 days) that required hospitalization, cardioversion, and led to discontinuation. No deaths were reported. All other AEs were mild to moderate in severity. Decreased white blood counts were the most commonly reported TEAE, followed by headache and constipation (Table). Reductions in white blood counts returned to normal range after study discontinuation without sequelae. Decreased neutrophils, lymphocytes and hemoglobin, and increased creatine kinase, alanine aminotransferase, and aspartate aminotransferase were reported, all of which resolved without sequelae. The mean absolute lymphocyte count for amiselimod exhibited a gradual decrease from predose (1.681 thou/uL) to a nadir of 0.424 thou/uL on day 27 (Figure). Changes to vital signs, physical examinations, and ECG parameters were within normal limits. Conclusions Upwardly titrated doses of amiselimod ranging from 0.4 to 1.6 mg were generally well tolerated in healthy subjects.

P045 Effect of Etrasimod on Circulating Lymphocyte Subsets: Data From a Randomized Phase 1 Study in Healthy Japanese and Caucasian Men.

BACKGROUND: Etrasimod, a selective sphingosine 1-phosphate (S1P) receptor 1,4,5 modulator that reduces peripheral lymphocytes and subsequently impedes their recruitment to sites of inflammation, is in development for chronic immune-mediated inflammatory diseases. Reduction in pro-inflammatory immune cells without causing broad immunosuppression is an important treatment goal in patients with these diseases. This study evaluated the effect of etrasimod on circulating lymphocyte subsets in healthy volunteers to improve understanding of its proposed mechanism of action. METHODS: In this phase 1, single-blind (subject only) pharmacokinetic (PK) and pharmacodynamic study, 49 healthy Japanese and Caucasian men were randomized to receive once daily oral etrasimod 1 mg (n = 20), 2 mg (n = 20), or matching placebo (n = 9) from Days 1 to 7, followed by a 7-day washout and a single dose on Day 15. Absolute lymphocyte counts (ALC) were determined by complete blood count with differential. Immune cell subsets were evaluated by flow cytometry from isolated peripheral blood mononuclear cells (PBMCs) collected pre-dose on Days 1, 3, 5, 7, and 15. Change from baseline on 24 different immune cell subtypes were evaluated using a mixed-effects model. Paired t-tests were computed to evaluate significant subtype modulations in etrasimod-treated groups vs placebo at Day 7. RESULTS: Compared with placebo, etrasimod 1 and 2 mg dosed daily for 7 days resulted in similar dose dependent reductions in ALC in both ethnic groups, with total lymphocytes returning to at least 84% of baseline at Day 15. Compared with placebo, etrasimod induced reductions in mean percent change from baseline to Day 7 in total T cells, total CD4+ and CD8+ T cells, naive CD4+ and CD8+ T cells, central memory CD4+ and CD8+ T cells, effector memory CD4+ and CD8+ T cells, Th2 and Th17 cells, and total B cells. Etrasimod resulted in greater decreases in naive and central memory T cells than in effector memory T cells. Decreased immune cell subsets recovered to at least 70% of baseline pre-dose on Day 15, after the 7-day washout period. No notable treatment effects were seen on monocytes, macrophages, or CD56dim NK cells. Changes in immune cell populations were similar between Japanese and Caucasian subjects. Etrasimod 1 and 2 mg once-daily dosing regimens were safe and generally well tolerated. No adverse events related to low lymphocyte values occurred. CONCLUSION: Etrasimod effects on ALC and immune cell subsets were consistent with its known mechanism of action and observations for other S1P receptor modulators. Little or no ethnic group differences in etrasimod effects on ALC and immune cell subsets were observed in this study. The effect of etrasimod on onset and offset of immune modulation is consistent with etrasimod PK, with a typical half-life of approximately 33 hours. The differential effects of etrasimod on immune cell subsets may allow for a reduction in inflammation while maintaining immune surveillance. The lymphocyte subset profile suggests that etrasimod reduces certain immune cells and behaves as a selective immunomodulator rather than as a broad immunosuppressive agent.

Abstract 14871: APD588, a Novel, Selective S1P Receptor Modulator, Regulates Inflammatory Responses and Attenuates Cardiac Dysfunction Following Experimental Myocardial Infarction in Mice

Recent studies have determined that chronic inflammation contributes to left ventricular (LV) remodeling following myocardial infarction (MI) leading to heart failure (HF). Evidence points to a critical role of T lymphocytes in driving the maladaptive inflammatory process associated with adverse tissue remodeling and cardiac dysfunction. FTY720, a non-selective sphingosine 1-phosphate (S1P) receptor modulator, elicits anti-inflammatory effects via inhibition of lymphocyte egress from secondary lymphoid organs and has been reported to improve cardiac remodeling and function post-MI. We hypothesized that APD588, a next-generation S1P receptor modulator with optimized S1P 1,5 receptor selectivity, would prevent cardiac remodeling and dysfunction following MI through modulation of T lymphocyte-mediated inflammatory responses. Efficacy of APD588 on cardiac function was assessed using C57BL/6N mice (n=7-10 mice/group) with experimental MI induced by coronary artery occlusion. Vehicle (VEH) or APD588 (0.3 mg/kg) was administered orally once daily starting at Day 3 post-MI and continued until Day 28. Blood samples were collected at Days 7 and 28 for lymphocyte count. Echocardiographic measurements, including LV ejection fraction (LVEF), were performed on Days 7, 14, and 28 post-MI. Administration of APD588 following MI resulted in a reduction of lymphocyte count at Days 7 and 28 post-MI, but only reached significance in the latter (VEH: 3.3 ± 0.5 x10 3 /μL; APD588: 1.3 ± 0.2 x10 3 /μL). Decreased cardiac function was observed at Day 7 post-MI (LVEF: 27.7 ± 3.6%, MI vs 45.7 ± 0.6%, Sham). No difference in LVEF was observed 7 days post-MI, however APD588 significantly improved LVEF at Day 28 post-MI, compared to vehicle (APD588: 35.7 ± 3.9%; VEH: 25.3 ± 3.9%). Therapies targeting inflammation in the pathophysiology of HF have shown limited success in the clinic. Novel strategies based on advancements in understanding the underlying immunobiology are warranted. Our results demonstrate that APD588 was effective at regulating lymphocyte activity and improved cardiac functional recovery following MI in mice. This supports the potential of S1P receptor modulation and other T lymphocyte-directed strategies as a targeted anti-inflammatory approach in HF.

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.

Central Modulation of Selective Sphingosine-1-Phosphate Receptor 1 Ameliorates Experimental Multiple Sclerosis

Future treatments of multiple sclerosis (MS), a chronic autoimmune neurodegenerative disease of the central nervous system (CNS), aim for simultaneous early targeting of peripheral immune function and neuroinflammation. Sphingosine-1-phosphate (S1P) receptor modulators are among the most promising drugs with both “immunological” and “non-immunological” actions. Selective S1P receptor modulators have been recently approved for MS and shown clinical efficacy in its mouse model, the experimental autoimmune encephalomyelitis (EAE). Here, we investigated the anti-inflammatory/neuroprotective effects of ozanimod (RPC1063), a S1P1/5 modulator recently approved in the United States for the treatment of MS, by performing ex vivo studies in EAE brain. Electrophysiological experiments, supported by molecular and immunofluorescence analysis, revealed that ozanimod was able to dampen the EAE glutamatergic synaptic alterations, through attenuation of local inflammatory response driven by activated microglia and infiltrating T cells, the main CNS-cellular players of EAE synaptopathy. Electrophysiological studies with selective S1P1 (AUY954) and S1P5 (A971432) agonists suggested that S1P1 modulation is the main driver of the anti-excitotoxic activity mediated by ozanimod. Accordingly, in vivo intra-cerebroventricular treatment of EAE mice with AUY954 ameliorated clinical disability. Altogether these results strengthened the relevance of S1P1 agonists as immunomodulatory and neuroprotective drugs for MS therapy.

Etrasimod, a Selective S1P1,4,5 Receptor Modulator, Exhibits Differential G Protein Signaling Compared to Other S1P Receptor Modulators

BackgroundEtrasimod (APD334) is an oral, selective sphingosine‐1‐phosphate (S1P) receptor modulator in development for atopic dermatitis and inflammatory bowel disease. In humans, S1P receptor modulators decrease heart rate at first‐dose due to initial on‐target S1P receptor 1 (S1P1) agonism in cardiac tissue. S1P1 agonism activates Gi and β‐arrestin signaling pathways: β‐arrestin activation leads to receptor internalization, the proposed mechanism by which S1P receptor modulators regulate lymphocyte trafficking; Gi‐coupled signaling activates G‐protein coupled inwardly rectifying potassium (GIRK) channels, that may contribute to the regulation of heart rate. Approved or investigational S1P receptor modulators have demonstrated different degrees of heart rate reduction and atrioventricular block in clinical studies. Such differences may be the result of differential signaling through the Gi coupled GIRK pathway.AimTo investigate S1P receptor expression in human sinoatrial (SA) node tissue, and the relative S1P1 mediated signaling events and GIRK channel activation of etrasimod and other S1P receptor modulators in the context of first dose heart rate effects.MethodsS1P receptor profiling was performed by qPCR in normal human primary SA node and right atrium samples. Potencies for multiple S1P receptor modulators to activate different S1P1 downstream signaling pathways (GTPγS, cAMP, β‐arrestin, S1P1 internalization) were measured in recombinant human‐S1P1 expressing cells. Gi mediated inhibition of cAMP was also measured in primary HUVEC. GIRK channel activation was measured in isolated adult human primary atrial myocytes.ResultsProfiling of S1P receptors in normal human atrial tissue and SA node demonstrated enriched expression of S1P1,2,3 with only minor expression of S1P4,5. Etrasimod was equipotent to other S1P receptor‐ modulators such as ozanimod, fingolimod, and siponimod in promoting β‐arrestin recruitment and S1P1 receptor internalization. Etrasimod was significantly less potent than ozanimod, fingolimod, and siponimod in assays measuring G‐protein activation (GTPγS binding and cAMP inhibition). In comparisons of GIRK activation, etrasimod was found to be a less potent activator of human atrial GIRK channels than ozanimod.ConclusionsWhen compared to other S1P1 modulators, the pharmacological profile of etrasimod at the S1P1 receptor suggests diminished capacity for signaling through Gi‐protein dependent pathways believed to be responsible for transient reductions in heart rate, while maintaining potent signaling in the β‐arrestin recruitment and receptor internalization related pathways underpinning the therapeutic efficacy of S1P1 modulators in immune‐mediated inflammatory disease settings.Support or Funding InformationThe study was sponsored by Arena Pharmaceuticals, Inc.