Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Discipline
      Discipline
      Clear All
      Discipline
  • Is Peer Reviewed
      Is Peer Reviewed
      Clear All
      Is Peer Reviewed
  • Item Type
      Item Type
      Clear All
      Item Type
  • Subject
      Subject
      Clear All
      Subject
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
      More Filters
      Clear All
      More Filters
      Source
    • Language
394 result(s) for "Benzyl Compounds - pharmacology"
Sort by:
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.
Siponimod vs placebo in active secondary progressive multiple sclerosis: a post hoc analysis from the phase 3 EXPAND study
BackgroundSiponimod is a sphingosine 1-phosphate receptor modulator approved for active secondary progressive multiple sclerosis (aSPMS) in most countries; however, phase 3 EXPAND study data are from an SPMS population with/without disease activity. A need exists to characterize efficacy/safety of siponimod in aSPMS.MethodsPost hoc analysis of participants with aSPMS (≥ 1 relapse in 2 years before study and/or ≥ 1 T1 gadolinium-enhancing [Gd +] magnetic resonance imaging [MRI] lesions at baseline) receiving oral siponimod (2 mg/day) or placebo for up to 3 years in EXPAND. Endpoints: 3-month/6-month confirmed disability progression (3mCDP/6mCDP); 3-month confirmed ≥ 20% worsening in Timed 25-Foot Walk (T25FW); 6-month confirmed improvement/worsening in Symbol Digit Modalities Test (SDMT) scores (≥ 4-point change); T2 lesion volume (T2LV) change from baseline; number of T1 Gd + lesions baseline–month 24; number of new/enlarging (N/E) T2 lesions over all visits.ResultsData from 779 participants with aSPMS were analysed. Siponimod reduced risk of 3mCDP/6mCDP vs placebo (by 31%/37%, respectively; p < 0.01); there was no significant effect on T25FW. Siponimod increased likelihood of 6-month confirmed SDMT improvement vs placebo (by 62%; p = 0.007) and reduced risk of 6-month confirmed SDMT worsening (by 27%; p = 0.060). Siponimod was associated with less increase in T2LV (1316.3 vs 13.3 mm3; p < 0.0001), and fewer T1 Gd + and N/E T2 lesions than placebo (85% and 80% reductions, respectively; p < 0.0001).ConclusionsIn aSPMS, siponimod reduced risk of disability progression and was associated with benefits on cognition and MRI outcomes vs placebo.Trial registrationClinicalTrials.gov number: NCT01665144.
Effects of Therapeutic and Supratherapeutic Doses of Siponimod (BAF312) on Cardiac Repolarization in Healthy Subjects
The International Conference on Harmonisation E14 guideline mandates an intensive cardiac safety evaluation in a clinical thorough QT study, typically in healthy subjects, for all new non-antiarrhythmic drugs with systemic bioavailability. This thorough QT study investigated the effects of therapeutic (2 mg) and supratherapeutic (10 mg) doses of siponimod (BAF312) on cardiac repolarization in healthy subjects. The study was a randomized, double-blind, parallel-group, placebo- and moxifloxacin-controlled, multiple oral dose study. Eligible subjects were randomly assigned to 3 groups to receive siponimod (up-titration to 2 and 10 mg over 18 days), placebo (Days −1 to 18), or moxifloxacin 400 mg Days 10 and 18). Triplicate ECGs were extracted at prespecified time points from Holter ECGs recorded from 1 hour predose until 24 hours postdose at baseline and on-treatment assessment Days 10 and 18. The primary pharmacodynamic variable was the time-matched, placebo-corrected, baseline-adjusted mean QTcF (ΔΔQTcF) at steady-state conditions. In addition, the pharmacokinetic parameters of siponimod and its main circulating metabolite M3 and its metabolite M5 were evaluated. Of the 304 enrolled subjects, 281 (92.4%) were included in the pharmacodynamic analysis and 270 (88.8%) completed the study. The upper bounds of the 2-sided 90% confidence intervals (CIs) for ΔΔQTcF at both siponimod doses were within the regulatory threshold of 10 milliseconds (ms) at all predefined on-treatment time points, with the absence of any dose-related effects. The highest observed upper limits of the 2-sided 90% CIs of 9.8 and 9.6 ms for therapeutic and supratherapeutic doses, respectively, were both observed at 3 hours postdose. No treatment-emergent QTc values >480 ms and no QTc increases of >60 ms from baseline were observed. Similar results were obtained with individualized heart rate correction of cardiac repolarization (QTcI). Assay validity was demonstrated by maximum ΔΔQTcF of >5 ms after 400 mg moxifloxacin on both on-treatment assessment days. The selected supratherapeutic dose produced approximately 5-fold higher exposures (Cmax and AUC) than the therapeutic dose, and was considered appropriate to investigate the effects of siponimod on QT/QTc at substantial multiples of the anticipated maximum therapeutic exposure. The findings provide evidence that siponimod is not associated with a significant arrhythmogenic potential related to QT prolongation.
Cardiac Effects of Siponimod (BAF312) Re-initiation After Variable Periods of Drug Discontinuation in Healthy Subjects
The goal of this study was to investigate the effect of siponimod treatment re-initiation on the initial negative chronotropic effects and cardiac rhythm after variable drug discontinuation periods. This partially double-blind, randomized, placebo-controlled study was conducted in healthy subjects. Siponimod doses (0.5–4.0 mg) and placebo were evaluated in combination with drug discontinuation periods ranging from 48 to 192 hours. Twelve-lead Holter ECGs were performed from 1.5 hours before until 24 hours after single-dose re-initiation. Atrioventricular blocks (AVBs) and sinus pauses (RR >2 seconds) were categorized according to dose level, discontinuation period, and resting and nonresting hours. Of the enrolled 138 subjects, 117 were evaluated. Demographic and baseline characteristics were comparable between the treatment groups. Subjects rechallenged at the combination of 4 mg/192 hours (highest investigated dose and longest discontinuation period [7 missed doses]) exhibited the highest decrease in pooled, placebo-adjusted heart rate (HR) of 14.53 beats/min. The magnitude of the negative chronotropic effect of siponimod re-initiation was dependent on both dose and duration of treatment discontinuation. Regardless of the dose, the placebo-adjusted HR reduction at re-initiation of drug treatment after up to 96 hours of drug discontinuation remained <10 beats/min. Except for 1 outlier for HR decrease under the 96-hour/placebo combination, no outliers were observed for any combination up to and including the 96-hour discontinuation periods. Most of the AVBs and sinus pauses were observed during nocturnal hours concurrent with increased vagal tone. All detected AVBs and sinus pauses were asymptomatic and not considered clinically relevant. Siponimod could be safely re-initiated without retitration after drug discontinuation periods up to 96 hours. Retitration is required if patients miss ≥4 consecutive doses.
Bioavailability and Tolerability of Combination Treatment With Revaprazan 200 mg + Itopride 150 mg: A Randomized Crossover Study in Healthy Male Korean Volunteers
To date, no definitive treatment of functional dyspepsia (FD) has been proven to be effective and reasonably well-tolerated. Proton pump inhibitors (PPIs) combined with prokinetic agents are considered an effective option. Revaprazan is a selective potassium-competitive acid blocker that reversibly inhibits gastric H+/K+-ATPase and shows effective acid suppression comparable to PPIs. Itopride is a prokinetic agent that has anticholinesterase activity as well as dopamine D2 receptor antagonistic activity. For this reason, revaprazan and itopride have been prescribed for FD; however, no available studies have reported the pharmacokinetic interactions of these 2 drugs. The objective of this study was to compare the bioavailability and tolerability of revaprazan and itopride combination therapy to those of equally dosed monotherapies to acquire basic drug–drug interaction information about revaprazan. This multiple-dose, randomized crossover study was conducted in healthy male Korean subjects. Subjects received, in randomized sequence, a 7-day oral dose of revaprazan 200 mg once daily, itopride 50 mg TID, or both. Each treatment period was separated by a 7-day washout period. Blood samples were collected for up to 24 hours following the last dose at steady state, and drug concentrations were determined using validated LC/MS-MS. Pharmacokinetic properties were obtained using noncompartmental analysis. Drug tolerability was assessed throughout the study, using measurements of vital signs, clinical chemistry testing, and interviews. A total of 30 subjects were enrolled in the study. Among them, 28 subjects completed revaprazan treatment, and 27 completed the study (3 subjects were withdrawn). The geometric mean ratios (GMRs) (90% CI) of Cmax,ss, and AUCτ,ss with revaprazan were 0.92 (0.84–1.00) and 0.96 (0.89–1.03), respectively. The GMRs of Cmax,ss and AUCτ,ss with itopride were 1.07 (0.96–1.20) and 1.12 (1.06–1.18), respectively. A total of 15 adverse events (AEs) were reported in 8 subjects. All AEs were considered to be mild, and there were no clinically significant differences between treatment groups. The findings from this study suggest bioequivalence between revaprazan given as monotherapy and in combination with itopride in these healthy Korean male volunteers, with no clinical significant drug–drug interaction. All treatments in this study was generally well tolerated. ClinicalTrials.gov identifier: NCT0133289.
Sphingosine 1-phosphate receptor modulators in multiple sclerosis and other conditions
The sphingosine 1-phosphate (S1P) signalling pathways have important and diverse functions. S1P receptors (S1PRs) have been proposed as a therapeutic target for various diseases due to their involvement in regulation of lymphocyte trafficking, brain and cardiac function, vascular permeability, and vascular and bronchial tone. S1PR modulators were first developed to prevent rejection by the immune system following renal transplantation, but the only currently approved indication is multiple sclerosis. The primary mechanism of action of S1PR modulators in multiple sclerosis is through binding S1PR subtype 1 on lymphocytes resulting in internalisation of the receptor and loss of responsiveness to the S1P gradient that drives lymphocyte egress from lymph nodes. The reduction in circulating lymphocytes presumably limits inflammatory cell migration into the CNS. Four S1PR modulators (fingolimod, siponimod, ozanimod, and ponesimod) have regulatory approval for multiple sclerosis. Preclinical evidence and ongoing and completed clinical trials support development of S1PR modulators for other therapeutic indications.
An allosteric mechanism for potent inhibition of human ATP-citrate lyase
ATP-citrate lyase (ACLY) is a central metabolic enzyme and catalyses the ATP-dependent conversion of citrate and coenzyme A (CoA) to oxaloacetate and acetyl-CoA 1 – 5 . The acetyl-CoA product is crucial for the metabolism of fatty acids 6 , 7 , the biosynthesis of cholesterol 8 , and the acetylation and prenylation of proteins 9 , 10 . There has been considerable interest in ACLY as a target for anti-cancer drugs, because many cancer cells depend on its activity for proliferation 2 , 5 , 11 . ACLY is also a target against dyslipidaemia and hepatic steatosis, with a compound currently in phase 3 clinical trials 4 , 5 . Many inhibitors of ACLY have been reported, but most of them have weak activity 5 . Here we report the development of a series of low nanomolar, small-molecule inhibitors of human ACLY. We have also determined the structure of the full-length human ACLY homo-tetramer in complex with one of these inhibitors (NDI-091143) by cryo-electron microscopy, which reveals an unexpected mechanism of inhibition. The compound is located in an allosteric, mostly hydrophobic cavity next to the citrate-binding site, and requires extensive conformational changes in the enzyme that indirectly disrupt citrate binding. The observed binding mode is supported by and explains the structure–activity relationships of these compounds. This allosteric site greatly enhances the ‘druggability’ of ACLY and represents an attractive target for the development of new ACLY inhibitors. The structure of human ATP-citrate lyase, in complex with a newly developed small-molecule inhibitor, shows extensive conformational changes that reveal an allosteric site for the inhibitor to bind and indirectly compete with the citrate substrate.
Differential activation mechanisms of lipid GPCRs by lysophosphatidic acid and sphingosine 1-phosphate
Lysophospholipids are bioactive lipids and can signal through G-protein-coupled receptors (GPCRs). The best studied lysophospholipids are lysophosphatidic acid (LPA) and sphingosine 1-phosphate (S1P). The mechanisms of lysophospholipid recognition by an active GPCR, and the activations of lysophospholipid GPCR–G-protein complexes remain unclear. Here we report single-particle cryo-EM structures of human S1P receptor 1 (S1P 1 ) and heterotrimeric G i complexes formed with bound S1P or the multiple sclerosis (MS) treatment drug Siponimod, as well as human LPA receptor 1 (LPA 1 ) and G i complexes in the presence of LPA. Our structural and functional data provide insights into how LPA and S1P adopt different conformations to interact with their cognate GPCRs, the selectivity of the homologous lipid GPCRs for S1P versus LPA, and the different activation mechanisms of these GPCRs by LPA and S1P. Our studies also reveal specific optimization strategies to improve the MS-treating S1P 1 -targeting drugs. Liu et al. report structures of human sphingosine 1-phosphate (S1P) receptor 1 (S1P 1 ) in complex with Gi and S1P or the multiple sclerosis (MS) drug Siponimod, as well as human lysophosphatidic acid (LPA) receptor 1 (LPA 1 ) in complex with Gi and LPA, revealing distinct conformations of the lysophospholipids interacting with their cognate GPCRs.
Comparative Analysis of Estragole, Methyleugenol, Myristicin, and Elemicin Regarding Micronucleus Formation in V79 Cells
Alkenylbenzenes occur as natural constituents in a variety of edible plants, in particular those herbs and spices used to give a distinctive flavor to a range of food and feed items. Some alkenylbenzenes with relevance for food, such as estragole and methyleugenol, are known to be genotoxic and carcinogenic in rodents. However, the genotoxic and carcinogenic potential of other structurally related alkenylbenzenes, such as myristicin and elemicin, is still under scientific discussion. Here, we investigated the potential of myristicin and elemicin to induce micronuclei (MN) in V79 cells in comparison to that of estragole and methyleugenol. In addition, we determined the impact of these alkenylbenzenes on cell viability and on the induction of apoptosis and necrosis. All tested alkenylbenzenes affected cell viability in a concentration-dependent manner, albeit to varying degrees. Regarding MN formation, elemicin induced a weak but statistically significant response at 100 µM and 500 µM in the absence of an exogenous metabolizing system (S9 mix). Negative results were obtained for estragole and myristicin at the highest tested non-cytotoxic concentration of 10 µM and 100 µM, respectively. For methyleugenol, the MN assay results were considered equivocal, since the observed change in MN induction was rather small and not supported by a concentration-related trend. These findings indicate that traditional in vitro test systems utilizing exogenous metabolizing systems have limited explanatory power with regard to the genotoxic potential of alkenylbenzenes.
Identification of a New Class of Antifungals Targeting the Synthesis of Fungal Sphingolipids
Recent estimates suggest that >300 million people are afflicted by serious fungal infections worldwide. Current antifungal drugs are static and toxic and/or have a narrow spectrum of activity. Thus, there is an urgent need for the development of new antifungal drugs. The fungal sphingolipid glucosylceramide (GlcCer) is critical in promoting virulence of a variety of human-pathogenic fungi. In this study, we screened a synthetic drug library for compounds that target the synthesis of fungal, but not mammalian, GlcCer and found two compounds [ N ′-(3-bromo-4-hydroxybenzylidene)-2-methylbenzohydrazide (BHBM) and its derivative, 3-bromo- N ′-(3-bromo-4-hydroxybenzylidene) benzohydrazide (D0)] that were highly effective in vitro and in vivo against several pathogenic fungi. BHBM and D0 were well tolerated in animals and are highly synergistic or additive to current antifungals. BHBM and D0 significantly affected fungal cell morphology and resulted in the accumulation of intracellular vesicles. Deep-sequencing analysis of drug-resistant mutants revealed that four protein products, encoded by genes APL5 , COS111 , MKK1 , and STE2 , which are involved in vesicular transport and cell cycle progression, are targeted by BHBM. IMPORTANCE Fungal infections are a significant cause of morbidity and mortality worldwide. Current antifungal drugs suffer from various drawbacks, including toxicity, drug resistance, and narrow spectrum of activity. In this study, we have demonstrated that pharmaceutical inhibition of fungal glucosylceramide presents a new opportunity to treat cryptococcosis and various other fungal infections. In addition to being effective against pathogenic fungi, the compounds discovered in this study were well tolerated by animals and additive to current antifungals. These findings suggest that these drugs might pave the way for the development of a new class of antifungals. Fungal infections are a significant cause of morbidity and mortality worldwide. Current antifungal drugs suffer from various drawbacks, including toxicity, drug resistance, and narrow spectrum of activity. In this study, we have demonstrated that pharmaceutical inhibition of fungal glucosylceramide presents a new opportunity to treat cryptococcosis and various other fungal infections. In addition to being effective against pathogenic fungi, the compounds discovered in this study were well tolerated by animals and additive to current antifungals. These findings suggest that these drugs might pave the way for the development of a new class of antifungals.