Time-Varying Clearance in Milrinone Pharmacokinetics from Premature Neonates to Adolescents.

BACKGROUND AND OBJECTIVES: Milrinone is an inotrope and vasodilator used for prophylaxis or treatment of low cardiac output syndrome after weaning from cardiopulmonary bypass (CPB). It is renally eliminated and has an acceptable therapeutic range of 100-300 µg/L, but weight-based dosing alone is associated with poor target attainment. We aimed to develop a population pharmacokinetic model for milrinone from premature neonates to adolescents, and to evaluate how age, renal function and recovery from CPB may impact dose selection. METHODS: Fifty paediatric patients (aged 4 days to 16 years) were studied after undergoing cardiac surgery supported by CPB. Data from 29 premature neonates (23-28 weeks' postmenstrual age) treated for prophylaxis of low systemic blood flow were available for a pooled pharmacokinetic analysis. Population parameters were estimated using non-linear mixed effects modelling (NONMEM 7.5.1). RESULTS: There were 369 milrinone measurements available for analysis. A one-compartment model with zero-order input and first-order elimination was used to describe milrinone disposition. Population parameters were clearance 17.8 L/70 kg [95% CI 15.8-19.9] and volume 20.4 L/h/70 kg [95% CI 17.8-22.1]. Covariates included size, postmenstrual age and renal function for clearance, and size and postnatal age for volume. Milrinone clearance is reduced by 39.5% [95% CI 24.0-53.7] immediately after bypass, and recovers to baseline clearance with a half-time of 12.0 h [95% CI 9.7-15.2]. Milrinone volume was 2.07 [95% CI 1.87-2.27] times greater at birth than the population standard and decreased over the first days of life with a half-time of 0.977 days [95% CI 0.833-1.12]. CONCLUSION: Milrinone is predominately renally eliminated and so renal function is an important covariate describing variability in clearance. Increasing clearance over time likely reflects increasing cardiac output and renal perfusion due to milrinone and return to baseline following CPB.

Impact of fedratinib on the pharmacokinetics of transporter probe substrates using a cocktail approach.

INTRODUCTION: Fedratinib, an oral, selective Janus kinase 2 inhibitor, has been shown to inhibit P-glycoprotein (P-gp), breast cancer resistance protein (BCRP), organic anion transporting polypeptide (OATP) 1B1, OATP1B3, organic cation transporter (OCT) 2, and multidrug and toxin extrusion (MATE) 1 and MATE2-K in vitro. The objective of this study was to evaluate the influence of fedratinib on the pharmacokinetics (PK) of digoxin (P-gp substrate), rosuvastatin (OATP1B1/1B3 and BCRP substrate), and metformin (OCT2 and MATE1/2-K substrate). METHODS: In this nonrandomized, fixed-sequence, open-label study, 24 healthy adult participants received single oral doses of digoxin 0.25 mg, rosuvastatin 10 mg, and metformin 1000 mg administered as a drug cocktail (day 1, period 1). After a 6-day washout, participants received oral fedratinib 600 mg 1 h before the cocktail on day 7 (period 2). An oral glucose tolerance test (OGTT) was performed to determine possible influences of fedratinib on the antihyperglycemic effect of metformin. RESULTS: Plasma exposure to the three probe drugs was generally comparable in the presence or absence of fedratinib. Reduced metformin renal clearance by 36% and slightly higher plasma glucose levels after OGTT were observed in the presence of fedratinib. Single oral doses of the cocktail ± fedratinib were generally well tolerated. CONCLUSIONS: These results suggest that fedratinib has minimal impact on the exposure of P-gp, BCRP, OATP1B1/1B3, OCT2, and MATE1/2-K substrates. Since renal clearance of metformin was decreased in the presence of fedratinib, caution should be exercised in using coadministered drugs that are renally excreted via OCT2 and MATEs. TRIAL REGISTRATION: Clinicaltrials.gov NCT04231435 on January 18, 2020.

Increasing the Power of Polyphenols through Nanoencapsulation for Adjuvant Therapy against Cardiovascular Diseases.

Polyphenols play a therapeutic role in vascular diseases, acting in inherent illness-associate conditions such as inflammation, diabetes, dyslipidemia, hypertension, and oxidative stress, as demonstrated by clinical trials and epidemiological surveys. The main polyphenol cardioprotective mechanisms rely on increased nitric oxide, decreased asymmetric dimethylarginine levels, upregulation of genes encoding antioxidant enzymes via the Nrf2-ARE pathway and anti-inflammatory action through the redox-sensitive transcription factor NF-κB and PPAR-γ receptor. However, poor polyphenol bioavailability and extensive metabolization restrict their applicability. Polyphenols carried by nanoparticles circumvent these limitations providing controlled release and better solubility, chemical protection, and target achievement. Nano-encapsulate polyphenols loaded in food grade polymers and lipids appear to be safe, gaining resistance in the enteric route for intestinal absorption, in which the mucoadhesiveness ensures their increased uptake, achieving high systemic levels in non-metabolized forms. Nano-capsules confer a gradual release to these compounds, as well as longer half-lives and cell and whole organism permanence, reinforcing their effectiveness, as demonstrated in pre-clinical trials, enabling their application as an adjuvant therapy against cardiovascular diseases. Polyphenol entrapment in nanoparticles should be encouraged in nutraceutical manufacturing for the fortification of foods and beverages. This study discusses pre-clinical trials evaluating how nano-encapsulate polyphenols following oral administration can aid in cardiovascular performance.

Dietary Flavonoids: Cardioprotective Potential with Antioxidant Effects and Their Pharmacokinetic, Toxicological and Therapeutic Concerns.

Flavonoids comprise a large group of structurally diverse polyphenolic compounds of plant origin and are abundantly found in human diet such as fruits, vegetables, grains, tea, dairy products, red wine, etc. Major classes of flavonoids include flavonols, flavones, flavanones, flavanols, anthocyanidins, isoflavones, and chalcones. Owing to their potential health benefits and medicinal significance, flavonoids are now considered as an indispensable component in a variety of medicinal, pharmaceutical, nutraceutical, and cosmetic preparations. Moreover, flavonoids play a significant role in preventing cardiovascular diseases (CVDs), which could be mainly due to their antioxidant, antiatherogenic, and antithrombotic effects. Epidemiological and in vitro/in vivo evidence of antioxidant effects supports the cardioprotective function of dietary flavonoids. Further, the inhibition of LDL oxidation and platelet aggregation following regular consumption of food containing flavonoids and moderate consumption of red wine might protect against atherosclerosis and thrombosis. One study suggests that daily intake of 100 mg of flavonoids through the diet may reduce the risk of developing morbidity and mortality due to coronary heart disease (CHD) by approximately 10%. This review summarizes dietary flavonoids with their sources and potential health implications in CVDs including various redox-active cardioprotective (molecular) mechanisms with antioxidant effects. Pharmacokinetic (oral bioavailability, drug metabolism), toxicological, and therapeutic aspects of dietary flavonoids are also addressed herein with future directions for the discovery and development of useful drug candidates/therapeutic molecules.

Impact of interleukin-6 on drug transporters and permeability in the hCMEC/D3 blood-brain barrier model.

The blood-brain barrier (BBB) is a highly selective membrane composed predominantly of brain capillary endothelial cells expressing drug efflux transporters that prevent substrates from accessing the brain. Inflammation is associated with central nervous system diseases and can impair BBB permeability via several mechanisms, including altered transporter and cell junction expression. This can modify the brain's exposure to drugs. However, comprehensive genomic analysis of the impact of interleukin (IL)-6, which plays a key role in the inflammatory response, on the BBB is lacking. In the present study, we analyzed the effects of exposure of hCMEC/D3 cells to 20 ng/mL IL-6 for 72 h. We performed RNA sequencing and ABC transporter efflux assays. Physiologically based pharmacokinetics (PBPK) simulations were conducted to evaluate the potential impact of IL-6 on the digoxin pharmacokinetics profile and brain exposure by decreasing BBB ABCB1 efflux activity. Exposure of hCMEC/D3 cells to IL-6 triggered the deregulation of numerous genes involved in barrier permeability, such as cell junctions, focal adherens complex, and cell adhesion molecules. We observed mild modification of the mRNA expression and efflux activities of ABC transporters. PBPK simulation showed that, if we only consider the impact of IL-6 on ABCB1 transporter, the modification of the digoxin pharmacokinetics profile and brain exposure is slight. IL-6 slightly affected the gene expression levels and activities of ABC transporters on BBB cells, exhibiting a weaker effect than on hepatic cells. However, inflammation may cause other modifications, such as altered BBB permeability, that could modify drug pharmacokinetics.

Isofraxidin: Synthesis, Biosynthesis, Isolation, Pharmacokinetic and Pharmacological Properties.

Isofraxidin (7-hydroxy-6, 8-dimethoxy coumarin) (IF) is a hydroxy coumarin with several biological and pharmacological activities. The plant kingdom is of the most prominent sources of IF, which, among them, Eleutherococcus and Fraxinus are the well-known genera in which IF could be isolated/extracted from their species. Considering the complex pathophysiological mechanisms behind some diseases (e.g., cancer, neurodegenerative diseases, and heart diseases), introducing IF as a potent multi-target agent, which possesses several herbal sources and the multiple methods for isolation/purification/synthesis, along with the unique pharmacokinetic profile and low levels of side effects, could be of great importance. Accordingly, a comprehensive review was done without time limitations until February 2020. IF extraction methods include microwave, mechanochemical, and ultrasound, along with other conventional methods in the presence of semi-polar solvents such as ethyl acetate (EtOAc). In addition to the isolation methods, related synthesis protocols of IF is also of great importance. From the synthesis point of view, benzaldehyde derivatives are widely used as precursors for IF synthesis. Along with the methods of isolation and biosynthesis, IF pharmacokinetic studies showed hopeful in vivo results of its rapid absorption after oral uses, leading to different pharmacological effects. In this regard, IF targets varieties of inflammatory mediators including nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), tumor necrosis factor-α (TNF-α), and matrix metalloproteinases (MMPs). thereby indicating anticancer, cardioprotective, and neuroprotective effects. This is the first review on the synthesis, biosynthesis, isolation, and pharmacokinetic and pharmacological properties of IF in combating different diseases.

Action of iron chelator on intramyocardial hemorrhage and cardiac remodeling following acute myocardial infarction.

Intramyocardial hemorrhage is an independent predictor of adverse outcomes in ST-segment elevation myocardial infarction (STEMI). Iron deposition resulting from ischemia-reperfusion injury (I/R) is pro-inflammatory and has been associated with adverse remodeling. The role of iron chelation in hemorrhagic acute myocardial infarction (AMI) has never been explored. The purpose of this study was to investigate the cardioprotection offered by the iron-chelating agent deferiprone (DFP) in a porcine AMI model by evaluating hemorrhage neutralization and subsequent cardiac remodeling. Two groups of animals underwent a reperfused AMI procedure: control and DFP treated (N = 7 each). A comprehensive MRI examination was performed in healthy state and up to week 4 post-AMI, followed by histological assessment. Infarct size was not significantly different between the two groups; however, the DFP group demonstrated earlier resolution of hemorrhage (by T2* imaging) and edema (by T2 imaging). Additionally, ventricular enlargement and myocardial hypertrophy (wall thickness and mass) were significantly smaller with DFP, suggesting reduced adverse remodeling, compared to control. The histologic results were consistent with the MRI findings. To date, there is no effective targeted therapy for reperfusion hemorrhage. Our proof-of-concept study is the first to identify hemorrhage-derived iron as a therapeutic target in I/R and exploit the cardioprotective properties of an iron-chelating drug candidate in the setting of AMI. Iron chelation could potentially serve as an adjunctive therapy in hemorrhagic AMI.

A review of pharmacological and pharmacokinetic properties of stachydrine.

Stachydrine is extracted from the leaves of Leonurus japonicus Houtt (or Motherwort, "Yi Mu Cao" in Traditional Chinese Medicine) and is the major bioactive ingredient. So far, stachydrine has demonstrated various bioactivities for the treatment of fibrosis, cardiovascular diseases, cancers, uterine diseases, brain injuries, and inflammation. The pharmacological and pharmacokinetic properties of stachydrine up to 2019 have been comprehensively searched and summarized. This review provides an updated summary of recent studies on the pharmacological activities of stachydrine. Many studies have demonstrated that stachydrine has strong anti-fibrotic properties (on various types of fibrosis) by inhibiting ECM deposition and decreasing inflammatory and oxidative stress through multiple molecular mechanisms (including TGF-ß, ERS-mediated apoptosis, MMPs/TIMPs, NF-κB, and JAK/STAT). The cardioprotective and vasoprotective activities of stachydrine are related to its inhibition of ß-MHC, excessive autophagy, SIRT1, eNOS uncoupling and TF, promotion of SERCA, and angiogenesis. In addition to its anticancer action, regulation of the uterus, neuroprotective effects, etc. the pharmacokinetic properties of stachydrine are also discussed.

Pirfenidone is a cardioprotective drug: Mechanisms of action and preclinical evidence.

Myocardial fibrosis is an endogenous response to different cardiac insults that may become maladaptive over time and contribute to the onset and progression of heart failure (HF). Fibrosis is a direct and indirect target of established HF therapies, namely inhibitors of the renin-angiotensin-aldosterone system, but its resilience to therapy warrants a search for novel, more targeted approaches to myocardial fibrosis. Pirfenidone is a drug approved for idiopathic pulmonary fibrosis, a severe form of idiopathic interstitial pneumonias. Pirfenidone is a small synthetic molecule with high oral bioavailability, exerting an antifibrotic activity, but also anti-oxidant and anti-inflammatory effects. These effects have been attributed to the inhibition of several growth factors (in particular transforming growth factor-ß, but also platelet-derived growth factor and beta fibroblast growth factor), matrix metalloproteinases, and pro-inflammatory mediators (such as interleukin-1ß and tumour necrosis factor-α), and possibly also an improvement of mitochondrial function and modulation of lymphocyte activation. Given the activation of similar profibrotic pathways in lung and heart disease, the crucial role of fibrosis in several cardiac disorders, and the wide spectrum of activity of pirfenidone, this drug has been evaluated with interest as a potential treatment for cardiac disorders. In animal studies, pirfenidone has shown cardioprotective effects across different species and in a variety of models of cardiomyopathy. In the present review we summarize the pharmacological characteristics of pirfenidone and the data from animal studies supporting its cardioprotective effects.

Improved cardioprotective effects of hesperidin solid lipid nanoparticles prepared by supercritical antisolvent technology.

Doxorubicin (DOX) is commonly used for the treatment of many types of cancers but its cardiotoxicity, owing to free radical formation, limits its clinical use. Hesperidin (HES), a flavanone glycoside, has been shown to exert multiple pharmacological actions including cardioprotective effects. Herein, we aim to formulate HES loaded solid lipid nanoparticles (SLNs) using supercritical antisolvent (SAS) technology to improve the oral delivery of HES. Process parameters were optimized to produce small size (175.3 ±â€¯3.6 nm) HES-SLNs with high encapsulation efficiency (87.6 ±â€¯3.8 %). DSC and XRD showed that HES is amorphously dispersed in SLNs. Compared to HES, HES-SLNs resulted in a nearly 20-fold increase in aqueous solubility and a nearly 5-fold increase in apparent permeability. Pharmacokinetics in rats revealed nearly 4.5-fold higher bioavailability of HES from SLN formulation compared to HES suspension. Data showed that HES-SLN significantly attenuated DOX-induced cardiotoxicity through lowering creatine kinase-muscle/brain, cardiac troponin I and improving histopathological scores as compared to the DOX group. HES-SLN also decreased malondialdehyde, increased catalase and superoxide dismutase of rats' heart to levels relatively comparable to control. Marked reductions in caspase-3 were also observed following HES-SLN treatment. Conclusively, these results describe a cardioprotective effect for HES-SLN against DOX-induced cardiotoxicity likely facilitated via suppression of oxidative stress and apoptosis.

Sesquiterpene lactone potentiates the immunomodulatory, antiparasitic and cardioprotective effects on anti-Trypanosoma cruzi specific chemotherapy.

We investigated the immunomodulatory, antiparasitic and cardioprotective effects of a sesquiterpene lactone (SL) administered alone or combined with benznidazole (Bz), in a murine model of Chagas' disease by in vitro and in vivo assays. Antiparasitic and cytotoxic potential of tagitinin C (SL) and Bz were tested in vitro against T. cruzi epimastigotes and cardiomyocytes. Swiss mice challenged with T. cruzi were also treated for 20 days with tagitinin C (10 mg/kg) alone and combined with Bz (100 mg/kg). Tagitinin C exhibited a higher antiparasitic (IC50: 1.15 µM) and cytotoxic (CC50 at 6.54 µM) potential than Bz (IC50: 35.81 µM and CC50: 713.5 µM, respectively). When combined, these drugs presented an addictive interaction, determining complete suppression of parasitemia and parasitological cure in all infected mice (100%) compared to those receiving Bz alone (70%). Anti-T. cruzi immunoglobulin G, and pro-inflammatory cytokines IFN-γ and TNF-α levels were reduced in animals treated with tagitinin C combined with Bz, while IL-10 production was unaffected. Heart inflammation was undetectable in 90% of the animals receiving this combination, while only 50% of the animals receiving Bz alone showed no evidence of myocarditis. Together, our findings indicated that the combination of tagitinin C and Bz exerts potent antiparasitic, immunomodulatory and cardioprotective effects. Due to the remarkable suppression of parasitemia and high parasitological cure, this combination was superior to Bz monotherapy, indicating a high potential for the treatment of Chagas's disease.

Population Pharmacokinetics of Milrinone in Infants, Children, and Adolescents.

Milrinone is a type 3 phosphodiesterase inhibitor used to improve cardiac output in critically ill infants and children. Milrinone is primarily excreted unchanged in the urine, raising concerns for toxic accumulation in the setting of renal dysfunction of critical illness. We developed a population pharmacokinetic model of milrinone using nonlinear mixed-effects modeling in NONMEM to perform dose-exposure simulations in children with variable renal function. We included children aged <21 years who received intravenous milrinone per clinical care. Plasma milrinone concentrations were measured using a validated liquid chromatography-tandem mass spectrometry assay (range 1-5000 ng/mL). We performed dose-exposure simulations targeting steady-state therapeutic concentrations of 100-300 ng/mL previously established in adults and children with cardiac dysfunction. We simulated concentrations over 48 hours in typical subjects with decreasing creatinine clearance (CrCl), estimated using the updated bedside Schwartz equation. Seventy-four patients contributed 111 plasma samples (concentration range, 4-634 ng/mL). The median (range) postmenstrual age (PMA) was 3.7 years (0-18), and median weight (WT) was 13.1 kg (2.6-157.7). The median serum creatinine and CrCl were 0.5 mg/dL (0.1-3.1) and 117.2 mL/min/1.73 m2 (13.1-261.3), respectively. A 1-compartment model characterized the pharmacokinetic data well. The final model parameterization was: Clearance (L/h) = 15.9*(WT [kg] / 70)0.75 * (PMA1.12 / (67.71.12 +PMA1.12 )*(CrCl / 117)0.522 ; and Volume of Distribution (L) = 32.2*(WT [kg] / 70). A loading dose of 50 µg/kg followed by a continuous infusion of 0.5 µg/kg/min resulted in therapeutic concentrations, except when CrCl was severely impaired at ≤30 mL/min/1.73 m2 . In this setting, a 25 µg/kg loading dose and 0.25 µg/kg/min continuous infusion resulted in therapeutic exposures.

Toxicity, bioactivity, release of H2S in vivo and pharmaco-kinetics of H2S-donors with thiophosphamide structure.

H2S donors are substitutes of H2S with various biological activities like inhibiting the inflammatory response and protecting myocardial cells from injury. In order to confirm whether the H2S donors have drug-like properties, two series thiophosphamide H2S donors were evaluated including toxicity, bioactivity and pharmacokinetic properties in vivo and in vitro. The following results were obtained. Firstly, all the compounds released H2S under measuring condition; with the increase of pH value, the H2S release rate of all the compounds decreased and the amount reduced, but pH value had little effect on the maximum release of H2S. Secondly, in the organs and tissues of rats, the compounds released H2S in the same way as in PBS. In plasma, compound 1 reached the Cmax after administration 55 min, and no compound 1 was detected after 12 h; for compound 18, the Cmax reached only after administration 100 min, and after 6 h, compound 18 was not detected; in organs and tissues, the H2S-release rates were different from those in PBS, but the mechanism of H2S release was the same. Thirdly, in the test of toxicity, all the compounds displayed low toxicities to 5 cancer cells and W138 cell lines; compounds 1 and 18 had slight effect on the physiological tissue and function of rat liver at low concentration; the compounds had almost no effect on the hatching rate, survival rate of zebrafish embryos, and the spontaneous movement of zebrafish embryos at below 0.5 µM, but when they were over 1 µM, the compounds displayed inhibitory effect in the manner of concentration dependence. Fourthly, in the course of anti-inflammatory test, all the tested compounds significantly reduced the level of TNF-α and increased the level of IL-10; when they were 100 µM, the levels of IL-10 were three times as high as those in the control group. Among them, compounds 10 and 18 displayed stronger activities than the others. In addition, the compounds protected H9c2 cells from injure and improved myocardial injury through anti-oxidation pathway. In summary, the compounds have druglike properties due to low toxicity, better activity and good pharmacokinetic property. Therefore, they have potential to be as candidates to investigate further.

Effect of Oral Semaglutide on the Pharmacokinetics of Lisinopril, Warfarin, Digoxin, and Metformin in Healthy Subjects.

BACKGROUND: Oral semaglutide is a tablet co-formulation of the human glucagon-like peptide-1 (GLP-1) analog semaglutide with the absorption enhancer sodium N-(8-[2-hydroxybenzoyl] amino) caprylate (SNAC). The absorption of coadministered oral drugs may be altered due to enhancement by SNAC, potential gastric emptying delay by semaglutide, or other mechanisms. Two one-sequence crossover trials investigated the effect of oral semaglutide on the pharmacokinetics of lisinopril, warfarin, digoxin, and metformin. METHODS: In trial 1, 52 healthy subjects received lisinopril (20 mg single dose) or warfarin (25 mg single dose) with subsequent coadministration with SNAC alone (300 mg single dose), followed by oral semaglutide 20 mg once daily (steady state). In trial 2, 32 healthy subjects received digoxin (500 µg single dose) or metformin (850 mg twice daily for 4 days), with subsequent coadministration with SNAC alone followed by oral semaglutide, as in trial 1. RESULTS: There were no apparent effects of oral semaglutide on area under the plasma concentration-time curve (AUC) and maximum plasma concentration (Cmax) for lisinopril, warfarin, and digoxin. The AUC of metformin was increased by 32% (90% confidence interval 1.23-1.43) by oral semaglutide coadministration versus metformin alone, whereas the Cmax was unaffected. SNAC alone did not affect exposure of lisinopril, warfarin, digoxin, or metformin. Adverse events were in line with those previously observed for GLP-1 receptor agonists. CONCLUSIONS: Oral semaglutide or SNAC alone did not appear to affect the exposure of lisinopril, warfarin, or digoxin, and, based on its wide therapeutic index, the higher metformin exposure with oral semaglutide was not considered clinically relevant.

Nanotechnology-based formulations for resveratrol delivery: Effects on resveratrol in vivo bioavailability and bioactivity.

Resveratrol (RES), also known as 3,5,4'-trihydroxystilbene, is a polyphenolic phytoalexin that has been widely researched in the past decade due to its recognized numerous biological activities. Despite the potential benefits of RES, its effective use is limited due to its poor solubility, photosensitivity and rapid metabolism, which strongly undermine RES bioavailability and bioactivity. Thereby, recently, nanotechnology appeared as a potential strategy to circumvent RES physicochemical and pharmacokinetics constrains. However, only few studies have addressed the crucial in vivo suitability of the developed delivery systems to improve RES efficacy. Facing this scenario, in the present review, it is intended to present and discuss the in vivo resveratrol bioavailability and bioactivity, following its encapsulation or conjugation in nanotechnology-based carriers, contemplating their pharmacokinetics effectiveness.

Assessment of Drug-Drug Interactions between Taspoglutide, a Glucagon-Like Peptide-1 Agonist, and Drugs Commonly Used in Type 2 Diabetes Mellitus: Results of Five Phase I Trials.

BACKGROUND AND OBJECTIVE: Taspoglutide, a glucagon-like peptide-1 agonist, like native glucagon-like peptide-1, delays gastric emptying time and prolongs intestinal transit time, which may alter the pharmacokinetics of concomitantly administered oral drugs. The effect of taspoglutide on the pharmacokinetics of five oral drugs commonly used in patients with type 2 diabetes mellitus was assessed in healthy subjects. METHODS: Five clinical pharmacology studies evaluated the potential drug-drug interaction between multiple subcutaneous taspoglutide doses and a single dose of lisinopril, warfarin, and simvastatin and multiple doses of digoxin and an oral contraceptive containing ethinylestradiol and levonorgestrel. The extent of interaction was quantified using geometric mean ratios and 90% confidence intervals for the maximum plasma concentration and area under the plasma concentration-time curve. In addition to pharmacokinetics, pharmacodynamic effects were assessed for warfarin and the oral contraceptive. RESULTS: Among the tested drugs, the effect of taspoglutide on the pharmacokinetics of simvastatin was most pronounced, on the day of taspoglutide administration, the average exposure to simvastatin was decreased by - 26% and - 58% for the area under the plasma concentration-time curve and maximum plasma concentration, respectively, accompanied by an increase in average exposure to its active metabolite, simvastatin ß-hydroxy acid (+ 74% and + 23% for area under the plasma concentration-time curve and maximum plasma concentration, respectively). Although statistically significant changes in exposure were observed for other test drugs, the 90% confidence intervals for the geometric mean ratio for maximum plasma concentration and area under the plasma concentration-time curve were within the 0.7-1.3 interval. No clinically relevant changes on coagulation (for warfarin) and ovulation-suppressing activity (for the oral contraceptive) were apparent. CONCLUSION: Overall, multiple doses of taspoglutide did not result in changes in the pharmacokinetics of digoxin, an oral contraceptive containing ethinylestradiol and levonorgestrel, lisinopril, warfarin, and simvastatin that would be considered of clinical relevance. Therefore, no dose adjustments are warranted upon co-administration.

Population Pharmacokinetics and Dosing of Milrinone After Patent Ductus Arteriosus Ligation in Preterm Infants.

OBJECTIVES: The postoperative course of patent ductus arteriosus ligation is often complicated by postligation cardiac syndrome, occurring in 10-45% of operated infants. Milrinone might prevent profound hemodynamic instability and improve the recovery of cardiac function in this setting. The present study aimed to describe the population pharmacokinetics of milrinone in premature neonates at risk of postligation cardiac syndrome and give dosing recommendations. DESIGN: A prospective single group open-label pharmacokinetics study. SETTINGS: Two tertiary care neonatal ICUs: Tallinn Children's Hospital and Tartu University Hospital, Estonia. PATIENTS: Ten neonates with postmenstrual age of 24.6-30.1 weeks and postnatal age of 5-27 days undergoing patent ductus arteriosus ligation and at risk of postligation cardiac syndrome, based on echocardiographic assessment of left ventricular output of less than 200 mL/kg/min 1 hour after the surgery. INTERVENTIONS: Milrinone at a dose of 0.73 µg/kg/min for 3 hours followed by 0.16 µg/kg/min for 21 hours. Four blood samples from each patient for milrinone plasma concentration measurements were collected. MEASUREMENTS AND MAIN RESULTS: Concentration-time data of milrinone were analyzed with nonlinear mixed-effects modeling software (NONMEM Version 7.3 [ICON Development Solutions, Ellicott City, MD]). Probability of target attainment simulations gave a dosing schedule that maximally attains concentration targets of 150-250 µg/L. Milrinone pharmacokinetics was described by a one-compartmental linear model with allometric scaling to bodyweight and an age maturation function of glomerular filtration rate. Parameter estimates for a patient with the median weight were 0.350 (L/hr) for clearance and 0.329 (L) for volume of distribution. The best probability of target attainment was achieved with a loading dose of 0.50 µg/kg/min for 3 hours followed by 0.15 µg/kg/min (postmenstrual age < 27 wk) or 0.20 µg/kg/min (postmenstrual age ≥ 27 wk). CONCLUSIONS: Population pharmacokinetic modeling and simulations suggest a slow loading dose followed by maintenance infusion to reach therapeutic milrinone plasma concentrations within the timeframe of the postligation cardiac syndrome.

Is the combinational administration of doxorubicin and glutathione a reasonable proposal?

The combinational administration of antioxidants and chemotherapeutic agents during conventional cancer treatment is among one of the most controversial areas in oncology. Although the data on the combinational usage of doxorubicin (DOX) and glutathione (GSH) agents have been explored for over 20 years, the duration, administration route, and authentic rationality have not yet been fully understood yet. In the current study, we systematically investigated the pharmacokinetics (PK) and pharmacodynamics (PD) with both in vivo and in vitro models to elucidate the influence of GSH on the toxicity and efficacy of DOX. We first studied the cardioprotective and hepatoprotective effects of GSH in Balb/c mice, H9c2, and HL7702 cells. We showed that coadministration of exogenous GSH (5, 50, and 500 mg/kg per day, intragastric) significantly attenuated DOX-induced cardiotoxicity and hepatotoxicity by increasing intracellular GSH levels, whereas the elevated GSH concentrations did not affect the exposure of DOX in mouse heart and liver. From PK and PD perspectives, then the influences of GSH on the chemotherapeutic efficacy of DOX were investigated in xenografted nude mice and cancer cell models, including MCF-7, HepG2, and Caco-2 cells, which revealed that administration of exogenous GSH dose-dependently attenuated the anticancer efficacy of DOX in vivo and in vitro, although the elevated GSH levels neither influenced the concentration of DOX in tumors in vivo, nor the uptake of DOX in MCF-7 tumor cells in vitro. Based on the results we suggest that the combined administration of GSH and DOX should be contraindicated during chemotherapy unless DOX has caused serious hepatotoxicity and cardiotoxicity.

Prophylactic use of levosimendan in pediatric patients undergoing cardiac surgery: a prospective randomized controlled trial.

BACKGROUND: The administration of levosimendan prophylactically to patients undergoing cardiac surgery remains a controversial practice, and few studies have specifically assessed the value of this approach in pediatric patients. This study therefore sought to explore the safety and efficacy of prophylactic levosimendan administration to pediatric patients as a means of preventing low cardiac output syndrome (LCOS) based upon hemodynamic, biomarker, and pharmacokinetic readouts. METHODS: This was a single-center, double-blind, randomized, placebo-controlled trial. Patients ≤ 48 months old were enrolled between July 2018 and April 2019 and were randomly assigned to groups that received either placebo or levosimendan infusions for 48 h post-surgery, along with all other standard methods of care. LCOS incidence was the primary outcome of this study. RESULTS: A total of 187 patients were enrolled, of whom 94 and 93 received levosimendan and placebo, respectively. LCOS incidence did not differ significantly between the levosimendan and placebo groups (10 [10.6%] versus 18 [19.4%] patients, respectively; 95% confidence interval [CI] 0.19-1.13; p = 0.090) nor did 90-day mortality (3 [3.2%] versus 4 [4.3%] patients, CI 0.14-3.69, p = 0.693), duration of mechanical ventilation (median, 47.5 h and 39.5 h, respectively; p = 0.532), ICU stay (median, 114.5 h and 118 h, respectively; p = 0.442), and hospital stay (median, 20 days and 20 days, respectively; p = 0.806). The incidence of hypotension and cardiac arrhythmia did not differ significantly between the groups. Levels of levosimendan fell rapidly without any plateau in plasma concentrations during infusion. A multiple logistic regression indicated that randomization to the levosimendan group was a predictor of LCOS. CONCLUSIONS: Prophylactic levosimendan administration was safe in pediatric patients and had some benefit to postoperative hemodynamic parameters, but failed to provide significant benefit with respect to LCOS or 90-day mortality relative to placebo. TRIAL REGISTRATION: Name of the registry: Safety evaluation and therapeutic effect of levosimendan on the low cardiac output syndrome in patients after cardiopulmonary bypass. TRIAL REGISTRATION NUMBER: ChiCTR1800016594. Date of registration: 11 June 2018. URL of trial registry record: http://www.chictr.org.cn/index.aspx.