Siponimod pharmacokinetics, safety, and tolerability in combination with the potent CYP3A4 inhibitor itraconazole in healthy subjects with different CYP2C9 genotypes.

PURPOSE: To evaluate the PK and safety of siponimod, a substrate of CYP2C9/3A4, in the presence or absence of a CYP3A4 inhibitor, itraconazole. METHODS: This was an open-label study in healthy subjects (aged 18-50 years; genotype: CYP2C9 *1*2 [cohort 1; n = 17] or *1*3 [cohort 2; n = 13]). Subjects received siponimod 0.25-mg single dose in treatment period 1 (days 1-14), itraconazole 100 mg twice daily in treatment period 2 (days 15-18), and siponimod 0.25-mg single dose (day 19) with itraconazole until day 31 (cohort 1) or day 35 (cohort 2) in treatment period 3. PK of siponimod alone and with itraconazole and safety were assessed. RESULTS: Overall, 29/30 subjects completed the study. In treatment period 1, geometric mean AUCinf, T1/2, and median Tmax were higher while systemic clearance was lower in cohort 2 than cohort 1. In treatment period 3, siponimod AUC decreased by 10% (geo-mean ratio [90% confidence intervals]: 0.90 [0.84; 0.96]) and 24% (0.76 [0.69; 0.82]) in cohorts 1 and 2, respectively. Siponimod Cmax was similar between treatment periods 1 and 3. In both cohorts, the Cmax and AUC of the metabolites (M17, M3, and M5) decreased in the presence of itraconazole. All adverse events were mild. CONCLUSIONS: The minor albeit significant reduction in plasma exposure of siponimod and its metabolites by itraconazole was unexpected. While the reason is unclear, the results suggest that coadministration of the two drugs would not cause a considerable increase of siponimod exposure independent of CYP2C9 genotype.

Comparative pharmacokinetic evaluation of extended release itopride HCl pellets with once daily tablet formulation in healthy human subjects: a two treatment, four period crossover study in fasted and fed condition.

OBJECTIVE: In this study, pharmacokinetics (PKs) and bioavailability of newly developed extended release (ER) Itopride HCl 150 mg encapsulated ER pellets (test) and 150 mg Ganaton ER once-daily (OD) tablets (reference) were compared and evaluated under fasted and fed conditions. METHODS: Twelve healthy human subjects were enrolled in a single dose, randomized; two treatments, two sequences, four period crossover study. A modified and validated liquid chromatographic method was used for the estimation of Itopride HCl in plasma samples. The data were analyzed through non-compartmental model using PK software Phoenix Winnonlin version 7. The outcome was measured on logarithmically transformed data, where p > 0.05 was considered as non-significant with 90% CI limit of 0.8-1.25. RESULTS: The Cmax, AUC0-t, and AUC0-∞ values of Itopride HCl 150 mg ER pellets versus that of OD 150 mg tablets, in fed and fasted states, were within the limits specified by FDA to establish bioequivalence. The relative bioavailability of Itopride HCl 150 mg ER pellets were 1.019 (fed) and 1.081(fasted). The 90% CIs of AUC values for Itopride HCl 150 mg ER pellets and OD 150 mg tablets in fed versus fast were significantly greater and were not within 80-125% limit. CONCLUSION: The test and reference formulations had similar pharmacokinetic parameters in each condition studied. However, an increase in the amount of drug was observed in the fed state.

Siponimod pharmacokinetics, safety, and tolerability in combination with rifampin, a CYP2C9/3A4 inducer, in healthy subjects.

PURPOSE: To assess the potential pharmacokinetic (PK) interactions between siponimod and rifampin, a strong CYP3A4/moderate CYP2C9 inducer, in healthy subjects. METHODS: This was a confirmatory, open-label, multiple-dose two-period study in healthy subjects (aged 18-45 years). In Period 1 (Days 1-12), siponimod was up-titrated from 0.25 to 2 mg over 5 days (Days 1-6) followed by 2 mg once daily on days 7-12. In Period 2, siponimod 2 mg qd was co-administered with rifampin 600 mg qd (Days 13-24). Primary assessments included PK of siponimod (Days 12 and 24; maximum steady-state plasma concentration [Cmax,ss], median time to achieve Cmax,ss [Tmax, ss], and area under the curve at steady state [AUCtau,ss]). Key secondary assessments were PK of M3 and M5 metabolites, and safety/tolerability including absolute lymphocyte count (ALC). RESULTS: Of the 16 subjects enrolled (age, mean ± standard deviation [SD] 31 ± 8.3 years; men, n = 15), 15 completed the study. In Period 1, siponimod geometric mean Cmax,ss (28.6 ng/mL) was achieved in 4 h (median Tmax,ss; range, 1.58-8.00) and the geometric mean AUCtau,ss was 546 h × ng/mL. In Period 2, the siponimod geometric mean Cmax,ss and AUCtau,ss decreased to 15.7 ng/mL and 235 h × ng/mL, respectively; median Tmax remained unchanged (4 h). Rifampin co-administration increased M3 Cmax,ss by 53% while M5 Cmax,ss remained unchanged. The AUCtau,ss of M3 and M5 decreased by 10% and 37%, respectively. The majority of adverse events reported were mild, with a higher frequency during Period 2 (86.7%) versus Period 1 (50%). The mean ALC increased slightly under rifampin co-administration but remained below 1.0 × 109/L. CONCLUSIONS: The study findings suggest that in the presence of rifampin, a strong CYP3A4/moderate CYP2C9 inducer, siponimod showed significant decrease in Cmax,ss (45%) and AUCtau,ss (57%) in healthy subjects.

In vitro studies and in silico predictions of fluconazole and CYP2C9 genetic polymorphism impact on siponimod metabolism and pharmacokinetics.

PURPOSE: The purpose of the study is to investigate the enzyme(s) responsible for siponimod metabolism and to predict the inhibitory effects of fluconazole as well as the impact of cytochrome P450 (CYP) 2C9 genetic polymorphism on siponimod pharmacokinetics (PK) and metabolism. METHODS: In vitro metabolism studies were conducted using human liver microsomes (HLM), and enzyme phenotyping was assessed using a correlation analysis method. SimCYP, a physiologically based PK model, was developed and used to predict the effects of fluconazole and CYP2C9 genetic polymorphism on siponimod metabolism. Primary PK parameters were generated using the SimCYP and WinNonlin software. RESULTS: Correlation analysis suggested that CYP2C9 is the main enzyme responsible for siponimod metabolism in humans. Compared with the CYP2C9*1/*1 genotype, HLM incubations from CYP2C9*3/*3 and CYP2C9*2/*2 donors showed ~ 10- and 3-fold decrease in siponimod metabolism, respectively. Simulations of enzyme contribution predicted that in the CYP2C9*1/*1 genotype, CYP2C9 is predominantly responsible for siponimod metabolism (~ 81%), whereas in the CYP2C9*3/*3 genotype, its contribution is reduced to 11%. The predicted exposure increase of siponimod with fluconazole 200 mg was 2.0-2.4-fold for CYP2C9*1/*1 genotype. In context of single dosing, the predicted mean area under the curve (AUC) is 2.7-, 3.0- and 4.5-fold higher in the CYP2C9*2/*2, CYP2C9*2/*3 and CYP2C9*3/*3 genotypes, respectively, compared with the CYP2C9*1/*1 genotype. CONCLUSION: .Enzyme phenotyping with correlation analysis confirmed the predominant role of CYP2C9 in the biotransformation of siponimod and demonstrated the functional consequence of CYP2C9 genetic polymorphism on siponimod metabolism. Simulation of fluconazole inhibition closely predicted a 2-fold AUC change (ratio within ~ 20% deviation) to the observed value. In silico simulation predicted a significant reduction in siponimod clearance in the CYP2C9*2/*2 and CYP2C9*3/*3 genotypes based on the in vitro metabolism data; the predicted exposure was close (within 30%) to the observed results for the CYP2C9*2/*3 and CYP2C9*3/*3 genotypes.

Characterization and Prediction of Cardiovascular Effects of Fingolimod and Siponimod Using a Systems Pharmacology Modeling Approach.

Sphingosine 1-phosphate (S1P) receptor agonists are associated with cardiovascular effects in humans. This study aims to develop a systems pharmacology model to identify the site of action (i.e., primary hemodynamic response variable) of S1P receptor agonists, and to predict, in a quantitative manner, the cardiovascular effects of novel S1P receptor agonists in vivo. The cardiovascular effects of once-daily fingolimod (0, 0.1, 0.3, 1, 3, and 10 mg/kg) and siponimod (3 and 15 mg/kg) were continuously recorded in spontaneously hypertensive rats and Wistar-Kyoto rats. The results were analyzed using a recently developed systems cardiovascular pharmacology model, i.e. the CVS model; total peripheral resistance and heart rate were identified as the site of action for fingolimod. Next, the CVS model was interfaced with an S1P agonist pharmacokinetic-pharmacodynamic (PKPD) model. This combined model adequately predicted, in a quantitative manner, the cardiovascular effects of siponimod using in vitro binding assays. In conclusion, the combined CVS and S1P agonist PKPD model adequately describes the hemodynamic effects of S1P receptor agonists in rats and constitutes a basis for the prediction, in a strictly quantitative manner, of the cardiovascular effects of novel S1P receptor agonists.

Recent progress in prodrug design strategies based on generally applicable modifications.

The development of prodrugs has progressed with the aim of improving drug bioavailability by overcoming various barriers that reduce drug benefits in clinical use, such as stability, duration, water solubility, side effect profile, and taste. Many conventional drugs act as the precursors of an active agent in vivo; for example, the anti-HIV agent azidothymidine (AZT) is converted into its corresponding active triphosphate ester in the body, meaning that AZT is a prodrug in the broadest sense. However prodrug design is generally difficult owing to the lack of general versatility. Thus, these prodrugs, broadly defined, are often discovered by chance or trial-and-error. Recently, many prodrugs that could release the corresponding parent drugs with or without enzymatic action under physiological conditions have been reported. These prodrugs can be easily designed and synthesized because of their generally applicable modifications. This digest paper provides an overview of recent development in prodrug strategies for drugs with a carboxylic acid or hydroxyl/amino group on the basis of a generally applicable modification strategy, such as esterification, amidation, or benzylation.

Physiologically based kinetic modeling of the bioactivation of myristicin.

The present study describes physiologically based kinetic (PBK) models for the alkenylbenzene myristicin that were developed by extension of the PBK models for the structurally related alkenylbenzene safrole in rat and human. The newly developed myristicin models revealed that the formation of the proximate carcinogenic metabolite 1'-hydroxymyristicin in liver is at most 1.8 fold higher in rat than in human and limited for the ultimate carcinogenic metabolite 1'-sulfoxymyristicin to (2.8-4.0)-fold higher in human. In addition, a comparison was made between the relative importance of bioactivation for myristicin and safrole. Model predictions indicate that for these related compounds, the formation of the 1'-sulfoxy metabolites in rat and human liver is comparable with a difference of <2.2-fold over a wide dose range. The results from this PBK analysis support that risk assessment of myristicin may be based on the BMDL10 derived for safrole of 1.9-5.1 mg/kg bw per day. Using an estimated daily intake of myristicin of 0.0019 mg/kg bw per day resulting from the use of herbs and spices, this results in MOE values for myristicin that amount to 1000-2700, indicating a priority for risk management. The results obtained illustrate that PBK modeling provides insight into possible species differences in the metabolic activation of myristicin. Moreover, they provide an example of how PBK modeling can facilitate a read-across in risk assessment from a compound for which in vivo toxicity studies are available to a related compound for which tumor data are not reported, thus contributing to alternatives in animal testing.

Pharmacokinetics, safety, and tolerability of siponimod (BAF312) in subjects with severe renal impairment: A single-dose, open-label, parallel-group study
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OBJECTIVE: To investigate the pharmacokinetics (PK), safety, and tolerability of siponimod and selected inactive metabolites (M3 and M5) in subjects with varying degrees of renal impairment (RI) compared to demographically matched healthy subjects (HS). METHODS: The study enrolled subjects with severe RI (n = 8) and matched HS (n = 8). Subjects with moderate and mild RI were to be enrolled only if interim analysis showed ≥ 50% increase in maximum plasma concentration (Cmax) or area under the curve (AUC) of total and/or unbound siponimod in severe RI subjects vs. HS. All subjects received a single oral dose of siponimod 0.25 mg on day 1; PK and safety were evaluated during the follow-up (~ 13 days). RESULTS: PK of siponimod was marginally affected in severe RI subjects vs. HS: Cmax decreased by 8%, and AUClast and AUCinf increased by 23% and 24%, respectively; half-life (37 vs. 26 hours) and systemic clearance (2.9 vs. 3.4 L/h) were comparable. Siponimod plasma unbound (u) fraction at 4 hours post-dose was similar between the two groups (range: 0.0172 - 0.0550%). Cmax(u) was comparable while AUClast(u) and AUCinf(u) were increased by 33% compared to HS. M3 exposure was similar (Cmax decreased by 9%; AUClast and AUCinf increased by 11%) and M5 exposure was slightly lower (Cmax decreased by 26%; AUClast decreased by 16%) in subjects with severe renal impairment (RI) compared with matched HS. No adverse events were reported during this study. CONCLUSIONS: Changes in the plasma exposure of total and unbound siponimod and metabolites M3 and M5 were not considered to be clinically relevant. Further to severe RI, investigation of PK in subjects with mild and moderate RI was not warranted.
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Pharmacokinetics, safety, and tolerability of siponimod (BAF312) in subjects with different levels of hepatic impairment: a single-dose, open-label, parallel-group study
.

OBJECTIVE: To assess the pharmacokinetics (PK), safety, and tolerability of siponimod and major metabolites in subjects with mild, moderate, and severe hepatic impairment (HI) compared with demographically-matched healthy subjects (HS). METHODS: This open-label, parallel-group study enrolled 40 subjects (each HI group, n = 8; HS group, n = 16). A staged design was employed starting with the enrollment of subjects with mild HI, followed by those with moderate and severe HI. All subjects received single oral doses of 0.25 mg siponimod on day 1; PK and safety data were collected during the 21-day follow-up. RESULTS: All subjects had similar baseline characteristics and completed the study. No significant differences were observed in the plasma exposure of siponimod in mild, moderate, and severe HI groups vs. HS: Cmax changed by 16%, -13%, and -16%; AUC by 5%, -13%, and 15%, respectively. The unbound siponimod PK parameters vs. HS were similar in the mild HI, and increased in the moderate (Cmax, 15%; AUC, 17%) and severe HI groups (Cmax, 11%; AUC, 50%). Exposure of M3 and M5 also showed 2- to 5-fold increase, particularly in the moderate and severe HI groups vs HS. There were no clinically-relevant safety findings. CONCLUSIONS: Single oral doses of 0.25 mg siponimod were well tolerated, and HI did not significantly alter exposure to siponimod. Increase in the M3 and M5 metabolites requires further evaluation. These results do not warrant any dose adjustments of siponimod in subjects with HI.
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Development of a physiologically based pharmacokinetic model to predict the effects of flavin-containing monooxygenase 3 (FMO3) polymorphisms on itopride exposure.

Itopride, a substrate of FMO3, has been used for the symptomatic treatment of various gastrointestinal disorders. Physiologically based pharmacokinetic (PBPK) modeling was applied to evaluate the impact of FMO3 polymorphism on itopride pharmacokinetics (PK). The Asian populations within the Simcyp simulator were updated to incorporate information on the frequency, activity and abundance of FMO3 enzyme with different phenotypes. A meta-analysis of relative enzyme activities suggested that FMO3 activity in subjects with homozygous Glu158Lys and Glu308Gly mutations (Lys158 and Gly308) in both alleles is ~47% lower than those carrying two wild-type FMO3 alleles. Individuals with homozygous Lys158 and Gly308 mutations account for about 5% of the total population in Asian populations. A CLint of 9 µl/min/pmol was optimised for itopride via a retrograde approach as human liver microsomal results would under-predict its clearance by ~7.9-fold. The developed itopride PBPK model was first verified with three additional clinical studies in Korean and Japanese subjects resulting in a predicted clearance of 52 to 69 l/h, which was comparable to those observed (55 to 88 l/h). The model was then applied to predict plasma concentration-time profiles of itopride in Chinese subjects with wild type or homozygous Lys158 and Gly308 FMO3 genotypes. The ratios of predicted to observed AUC of itopride in subjects with each genotype were 1.23 and 0.94, respectively. In addition, the results also suggested that for FMO3 metabolised drugs with a safety margin of 2 or more, proactive genotyping FMO3 to exclude subjects with homozygous Lys158/Gly308 alleles may not be necessary.

Pharmacokinetic and pharmacodynamic interaction of siponimod (BAF312) and propranolol in healthy subjects.

OBJECTIVE: To evaluate the cardiac and pulmonary effects of siponimod (BAF312) and propranolol co-administration in healthy subjects. METHODS: Healthy subjects (n=76) were randomized in a doubleblind manner to receive propranolol at siponimod steady state (group A), siponimod at propranolol steady state (group B), placebo (group C) and propranolol (group D). Pharmacodynamic evaluations included maximum change from baseline in time-matched hourly average heart rate (Emax HR) and mean arterial blood pressure (Emax MABP) over 24 hours postdose, change from baseline in PR intervals, cardiac rhythm, and forced expiratory volume in 1 second (FEV1). Pharmacokinetic and safety parameters were also assessed. RESULTS: Siponimod and propranolol when administered alone resulted in similar HR decrease at steady state. Compared to propranolol alone, the combination at steady state had an additional 6.21 bpm (95%CI: 2.32, 10.11) decrease of mean EmaxHR, a decrease of 5.04 bpm (0.52, 9.56) for group A and 7.39 bpm (2.87, 11.90) for group B. A minor decrease in MABP and a trend towards PR interval increase were noted with co-administration treatment vs. propranolol alone. There were no episodes of second-degree atrioventricular blocks or sinus pauses>3 seconds. Baseline-corrected FEV1 was reduced by -0.07 L (95% CI: -0.17, 0.03) for group A and -0.05 L (-0.15, 0.05) for group B vs. propranolol alone. There were no cardiovascular adverse events during coadministration treatment. CONCLUSIONS: Coadministration of siponimod and propranolol was well tolerated. Bradyarrhythmic effects were less pronounced when propranolol was added to siponimod steady-state therapy compared with siponimod addition to propranolol.

A Minimal ß-Lactone Fragment for Selective ß5c or ß5i Proteasome Inhibitors.

Broad-spectrum proteasome inhibitors are applied as anticancer drugs, whereas selective blockage of the immunoproteasome represents a promising therapeutic rationale for autoimmune diseases. We here aimed at identifying minimal structural elements that confer ß5c or ß5i selectivity on proteasome inhibitors. Based on the natural product belactosin C, we synthesized two ß-lactones featuring a dimethoxybenzyl moiety and either a methylpropyl (pseudo-isoleucin) or an isopropyl (pseudo-valine) P1 side chain. Although the two compounds differ only by one methyl group, the isoleucine analogue is six times more potent for ß5i (IC50=14 nM) than the valine counterpart. Cell culture experiments demonstrate the cell-permeability of the compounds and X-ray crystallography data highlight them as minimal fragments that occupy primed and non-primed pockets of the active sites of the proteasome. Together, these results qualify ß-lactones as a promising lead-structure motif for potent nonpeptidic proteasome inhibitors with diverse pharmaceutical applications.

Effect of two-linked mutations of the FMO3 gene on itopride metabolism in Chinese healthy volunteers.

PURPOSE: Itopride is an effective gastroprokinetic agent mainly used for the treatment of functional dyspepsia. Flavin-containing monooxygenase 3 (FMO3) has been confirmed to be the key enzyme involved in the main itopride metabolic pathway. We investigated whether the FMO3 genotypes can affect itopride metabolism in Chinese healthy volunteers. METHODS: Twelve healthy volunteers who had been genotyped for FMO3 gene were selected to participate in our study. Volunteers were given 50 mg itopride orally and then blood samples were collected from 0 to 24 h. The plasma concentrations of itopride and itopride N-oxide were determined by HPLC-MS/MS method. RESULTS: Itopride and itopride N-oxide both exhibit FMO3 genotype-dependent pharmacokinetic profiles. The area under the plasma concentration-time curve (AUC) of itopride increased by 127.82 ± 41.99 % (P < 0.001) and the AUC of itopride N-oxide decreased by 30.30 ± 25.70 % (P < 0.05) in homozygous FMO3 hhdd subjects (n = 6) compared with the HHDD group (n = 6). The CL/F value was lower in the hhdd group than that in the HHDD group (36.60 ± 7.06 vs. 80.20 ± 15.34 L/h, P < 0.001). But no significant differences in t1/2 value and tmax of itopride and itopride N-oxide were observed between these two genotypes. CONCLUSION: The FMO3 allele can significantly affect the metabolism of itopride. The pharmacokinetic parameters of both itopride and itopride N-oxide were significantly different between these two genotypes.

Dose titration of BAF312 attenuates the initial heart rate reducing effect in healthy subjects.

AIM: Previous studies have shown transient decreases in heart rate (HR) following administration of sphingosine 1-phosphate (S1P) receptor modulators including BAF312. This study was conducted to determine whether dose titration of BAF312 reduces or eliminates these effects. METHODS: Fifty-six healthy subjects were randomized 1:1:1:1 to receive BAF312 in one of two dose titration (DT) regimens (DT1 and DT2: 0.25-10 mg over 9-10 days), no titration (10 mg starting dose) or placebo. Pharmacodynamic and pharmacokinetic parameters were assessed. RESULTS: Neither DT1 nor DT2 resulted in clinically significant bradycardia or atrioventricular conduction effects. Both titration regimens showed a favourable difference on each of days 1-12 vs. the non-titration regimen on day 1 for HR effects (P < 0.0001). On day 1, the geometric mean ratio of the fraction from the previous day in minimum daily HR between DT1 and non-titration was 1.18 (95% confidence interval [CI] 1.13, 1.23) and 1.14 (95% CI 1.09, 1.18) for DT2 (both P < 0.05) with significant differences noted through to day 12. Non-titration HRs showed considerable separation from placebo throughout the study. There was no statistically significant reduction in HR vs. placebo on day 1 in either titration regimen. On days 3-7 subjects in DT1 and DT2 experienced minor reductions in HR vs. placebo (approximately 5 beats min⁻¹; P ≤ 0.0001). From days 9-12, HRs in both titration regimens were comparable with placebo. CONCLUSION: Both titration regimens effectively attenuated the initial bradyarrhythmia observed on day 1 of treatment with BAF312 10 mg.

Oxidative ipso substitution of 2,4-difluoro-benzylphthalazines: identification of a rare stable quinone methide and subsequent GSH conjugate.

In vitro metabolite identification and GSH trapping studies in human liver microsomes were conducted to understand the bioactivation potential of compound 1 [2-(6-(4-(4-(2,4-difluorobenzyl)phthalazin-1-yl)piperazin-1-yl)pyridin-3-yl)propan-2-ol], an inhibitor of the Hedgehog pathway. The results revealed the formation of a unique, stable quinone methide metabolite (M1) via ipso substitution of a fluorine atom and subsequent formation of a GSH adduct (M2). The stability of this metabolite arises from extensive resonance-stabilized conjugation of the substituted benzylphthalazine moiety. Cytochrome P450 (P450) phenotyping studies revealed that the formation of M1 and M2 were NADPH-dependent and primarily catalyzed by CYP3A4 among the studied P450 isoforms. In summary, an unusual and stable quinone methide metabolite of compound 1 was identified, and a mechanism was proposed for its formation via an oxidative ipso substitution.

In vivo drug interactions of itopride and trimethylamine mediated by flavin-containing monooxygenase 3 in humanized-liver mice.

Flavin-containing monooxygenase (FMO) catalyzes the oxygenation of a wide variety of medicines and dietary-derived compounds. However, little information is available regarding drug interactions mediated by FMO3 in vivo. Consequently, we investigated interactions between FMO substrates in humanized-liver mice. Trimethylamine-d9 and itopride were, respectively, intravenously and orally administered to humanized-liver mice (n = 5-7). The pharmacokinetic profiles of itopride (the victim drug) in the presence of trimethylamine (the perpetrator drug) were determined for 24 h after co-administration using liquid chromatography/tandem mass spectrometry. Itopride (10 mg/kg) was extensively oxygenated in humanized-liver mice to its N-oxide. The plasma concentrations of itopride N-oxide after co-administration of itopride and trimethylamine (10 and 100 mg/kg) were significantly suppressed in a dose-dependent manner, but only during the early phase, i.e., up to 2 h after co-administration. With the higher dose of trimethylamine, the areas under the concentration-time curves of itopride and its N-oxide significantly increased (1.6-fold) and decreased (to 60%), respectively; modeling suggested that these modified pharmacokinetics resulted from suppression of the in vivo hepatic intrinsic clearance (to 67%). These results suggest that food-derived trimethylamine may result in interactions with FMO drug substrates immediately after administration; however, the potential for this to occur in vivo may be limited.

Neuroprotective effects of macamide from maca (Lepidium meyenii Walp.) on corticosterone-induced hippocampal impairments through its anti-inflammatory, neurotrophic, and synaptic protection properties.

The present study aims to investigate the protective effects of N-(3-methoxybenzyl)-(9Z,12Z,15Z)-octadecatrienamide (M 18:3) on corticosterone-induced neurotoxicity. A neurotoxic model was established by subcutaneous injection of corticosterone (40 mg per kg bw) for 21 days. Depressive behaviors (the percentage of sucrose consumption, the immobility time in the forced swimming test, and the total distance in the open field test) were observed. The levels of the brain-derived neurotrophic factor, the contents of tumor necrosis factor-α and interleukin-6, and the numbers of positive cells of doublecortin and bromodeoxyuridine in the hippocampus were measured. The density of hippocampal neurons was calculated. The morphological changes of hippocampal neurons (the density of dendritic spines, the dendritic length, and the area and volume of dendritic cell bodies) were observed. The expression levels of synaptophysin, synapsin I, and postsynaptic density protein 95 were measured. Behavioral experiments showed that M 18:3 (5 and 25 mg per kg bw) could remarkably improve the depressive behaviors. The enzyme-linked immunosorbent assay showed that M 18:3 could considerably reduce hippocampal neuroinflammation and increase hippocampal neurotrophy. Nissl staining showed that M 18:3 could remarkably improve the corticosterone-induced decrease in the hippocampal neuron density. Immunofluorescence analysis showed that M 18:3 could considerably promote hippocampal neurogenesis. Golgi staining showed that M 18:3 could remarkably improve the corticosterone-induced changes in the hippocampal dendritic structure. Western blotting showed that M 18:3 could considerably increase the expression levels of synaptic-structure-related proteins in the hippocampus. In conclusion, the protective effects of M 18:3 may be attributed to the anti-inflammatory, neurotrophic, and synaptic protection properties.

Evaluation of anti-GERD activity of gastro retentive drug delivery system of itopride hydrochloride.

The present work describes the formulation and evaluation of the gastroretentive system of Itopride hydrochloride. In this research, we have formulated floating hydrogel-based microspheres employing calcium carbonate (CaCO(3)) as a gas forming agent dispersed in alginate matrix. In vitro characterizations such as drug content, particle size, and drug release were carried out. GI motility was determined by administration of charcoal meal to rats. Results demonstrated that prepared microspheres were spherical in shape with smooth surface, good loading efficiency, and excellent buoyancy. The gastro retentive dosage form of itiopride demonstrated significant antacid, anti-ulcer, and anti-GERD activity after 12 hours in comparison with the conventional dosage form.

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.

Nanoparticle BAF312@CaP-NP Overcomes Sphingosine-1-Phosphate Receptor-1-Mediated Chemoresistance Through Inhibiting S1PR1/P-STAT3 Axis in Ovarian Carcinoma.

PURPOSE: Platinum/paclitaxel-based chemotherapy is the strategy for ovarian cancer, but chemoresistance, inherent or acquired, occurs and hinders therapy. Therefore, further understanding of the mechanisms of drug resistance and adoption of novel therapeutic strategies are urgently needed. METHODS: In this study, we report that sphingosine-1-phosphate receptor-1 (S1PR1)-mediated chemoresistance for ovarian cancer. Then we developed nanoparticles with a hydrophilic PEG2000 chain and a hydrophobic DSPE and biodegradable CaP (calcium ions and phosphate ions) shell with pH sensitivity as a delivery system (CaP-NPs) to carry BAF312, a selective antagonist of S1PR1 (BAF312@CaP-NPs), to overcome the cisplatin (DDP) resistance of the ovarian cancer cell line SKOV3DR. RESULTS: We found that S1PR1 affected acquired chemoresistance in ovarian cancer by increasing the phosphorylated-signal transduction and activators of transcription 3 (P-STAT3) level. The mean size and zeta potential of BAF312@CaP-NPs were 116 ± 4.341 nm and -9.67 ± 0.935 mV, respectively. The incorporation efficiency for BAF312 in the CaP-NPs was 76.1%. The small size of the nanoparticles elevated their enrichment in the tumor, and the degradable CaP shell with smart pH sensitivity of the BAF312@CaP-NPs ensured the release of BAF312 in the acidic tumor niche. BAF312@CaP-NPs caused substantial cytotoxicity in DDP-resistant ovarian cancer cells by downregulating S1PR1 and P-STAT3 levels. CONCLUSION: We found that BAF312@CaP-NPs act as an effective and selective delivery system for overcoming S1PR1-mediated chemoresistance in ovarian carcinoma by inhibiting S1PR1 and P-STAT3.