Study In Healthy Male Volunteers Research Articles

Pharmacokinetic Interactions Between Bazedoxifene and Cholecalciferol: An Open-Label, Randomized, Crossover Study in Healthy Male Volunteers.

The combined administration of bazedoxifene, a tissue-selective estrogen receptor modulator, and cholecalciferol can be a promising therapeutic option for postmenopausal osteoporosis patients. This study aimed to examine the pharmacokinetic interactions between these two drugs and the tolerability of their combined administration in healthy male subjects. Thirty male volunteers were randomly assigned to one of the six sequences comprised of three treatments: bazedoxifene 20 mg monotherapy, cholecalciferol 1600 IU monotherapy, and combined bazedoxifene and cholecalciferol therapy. For each treatment, a single dose of the investigational drug(s) was administered orally, and serial blood samples were collected to measure the plasma concentrations of bazedoxifene and cholecalciferol. Pharmacokinetic parameters were calculated using the non-compartmental method. The point estimate and 90% confidence interval (CI) of the geometric mean ratio (GMR) were obtained to compare the exposures of combined therapy and monotherapy. The pharmacokinetic parameters compared were the maximum plasma concentration (Cmax) and the area under the plasma concentration-time curve from time zero to the last quantifiable concentration (AUClast). The safety and tolerability of the combined therapy were assessed in terms of the frequency and severity of adverse events (AEs). For bazedoxifene, the GMR (90% CI) of the combined therapy to monotherapy was 1.044 (0.9263-1.1765) for Cmax and 1.1329 (1.0232-1.2544) for AUClast. For baseline-adjusted cholecalciferol, the GMR (90% CI) of the combined therapy to monotherapy was 0.8543 (0.8005-0.9117) for Cmax and 0.8056 (0.7445-0.8717) for AUClast. The frequency of AEs observed was not significantly different between the combined therapy and monotherapy, and their severity was mild in all cases. A mild degree of pharmacokinetic interaction was observed when bazedoxifene and cholecalciferol were administered concomitantly to healthy male volunteers. This combined therapy was well tolerated at the dose levels used in the present study.

Association between Functional Parameters of Coagulation and Conventional Coagulation Tests in the Setting of Fluid Resuscitation with Balanced Crystalloid or Gelatine: A Secondary Analysis of an In Vivo Prospective Randomized Crossover Study.

Functional point-of-care tests (POCTs) have evolved into useful tools for diagnosing disorders of blood coagulation and fibrinolysis. We aimed to describe the in vivo association between standard and functional parameters of coagulation and fibrinolysis in the setting of acute hemodilution induced by an infusion of balanced crystalloid or synthetic gelatine solutions. This prospective randomized crossover in vivo study included healthy male volunteers aged 18–30 years. Enrolled participants were randomly assigned to receive either the Optilyte® or Geloplasma® infusion. Laboratory analysis included conventional coagulation parameters and rotational thromboelastometry (ROTEM) assays. A total of 25 healthy Caucasian males were included. ROTEM viscoelastic assays presented moderate to strong correlations with conventional coagulation tests, regardless of the fluid type utilized. Irrespectively of the extent of hemodilution, significant correlations remained unaffected. The strongest associations were found between the ROTEM clot formation and clot strength and the fibrinogen concentration and platelet count, and between the ROTEM clotting time and the APTT and PT. This in vivo experimental study in healthy male volunteers demonstrated that ROTEM may be used as a credible alternative to standard laboratory tests to assess blood coagulation and fibrinolysis in the setting of fluid resuscitation with both crystalloid and colloid solutions. The study was registered online in the ClinicalTrials.gov database (NCT05148650).

Results From Phase I Studies Investigating the Dose Linearity of Finerenone Tablets and the Influence of Food or pH-Modifying Comedications on its Pharmacokinetics in Healthy Male Volunteers

Finerenone is a nonsteroidal mineralocorticoid receptor antagonist that reduces the risk of adverse kidney and cardiovascular outcomes in patients with chronic kidney disease associated with type 2 diabetesmellitus. Clinical phase I studies with finerenone were carried out to assess its pharmacokinetics and the influence of common covariables on its absorption after oral administration. Three crossover studies in healthy male volunteers with single-dose administration of finerenone investigated the dose linearity of a film-coated tablet (1.25-10 mg [n = 24] and 10-20 mg [n = 18]), the effect of food on the 20 mg tablet (n = 18), and the effects of the proton-pump inhibitor omeprazole (4 days pre-treatment and co-administration 2 h before finerenone) and an aluminum/magnesium hydroxide-containing antacid (10 mL [Maalox®] 70 mVal, simultaneous intake) on the 10mg tablet (n = 10 and n = 11, respectively). Finerenone was rapidly absorbed (time to reach maximum plasma concentration [tmax] was 0.50-0.75 h). Area under the curve from zero to infinity (AUC∞) and the maximum concentration (Cmax) increased in proportion to dose in the range investigated in clinical phase II and phase III studies (1.25-20mg), with point estimates for the ratio of dose-normalized AUC∞ and Cmax (20 mg/10 mg, approved therapeutic doses) of 0.9943 and 0.9301. After the administration of finerenone 20mg with a high-fat, high-calorie meal, AUC∞ increased (+21%), Cmax decreased (-19%), and tmax was prolonged (2.47vs. 0.75 h) when compared with the fasting state. Omeprazole had no effect on finerenone AUC∞ and Cmax. Maalox had no effect on finerenone AUC∞ and led to a non-clinically-relevant decrease in Cmax (-19%). The pharmacokinetics of the finerenone film-coated tablet were linear. High-fat, high-calorie food had no clinically relevant effect on the pharmacokinetics of finerenone. In addition, pH-modifying comedications were not found to alter the pharmacokinetics of finerenone and were deemed safe for co-administration.

Evaluation of 1β-Hydroxylation of Deoxycholic Acid as a Non-Invasive Urinary Biomarker of CYP3A Activity in the Assessment of Inhibition-Based Drug-Drug Interaction in Healthy Volunteers.

In this study, we aimed to evaluate the utility of endogenous 1β-hydroxy-deoxycholic acid/total deoxycholic acid ratio (1β-OH-DCA/ToDCA) in spot urine as a surrogate marker of cytochrome P450 3A (CYP3A) activity in the assessment inhibition-based drug–drug interactions in healthy volunteers. This was accomplished through an open-label, three-treatment parallel-arm study in healthy male volunteers from Zimbabwe. Each group received itraconazole (ITZ; 100 mg once daily; n = 10), fluconazole (FKZ; 50 mg once daily; n = 9), or alprazolam (APZ; 1 mg once daily; n = 8) orally. Midazolam (MDZ), dosed orally and intravenously, was used as a comparator to validate the exploratory measures of CYP3A activity and the effects of known inhibitors. Urinary metabolic ratios of 1β-OH-DCA/ToDCA before and after CYP3A inhibitor treatment showed a similar magnitude of inhibitory effects of the three treatments as that measured by oral MDZ clearance. The maximum inhibition effect of a 75% reduction in the 1β-OH-DCA/ToDCA ratio compared to the baseline was achieved in the ITZ group following six once-daily doses of 100 mg. The correlations of the two markers for CYP3A inhibitor treatment were significant (rs = 0.53, p < 0.01). The half-life of urinary endogenous 1β-OH-DCA/ToDCA was estimated as four days. These results suggested that 1β-OH-DCA/ToDCA in spot urine is a promising convenient, non-invasive, sensitive, and relatively quickly responsive endogenous biomarker that can be used for CYP3A inhibition-based drug–drug interaction in clinical studies.

A pharmacokinetics study of proposed bevacizumab biosimilar MYL-1402O vs EU-bevacizumab and US-bevacizumab

PurposeBevacizumab is a recombinant humanized monoclonal antibody that inhibits vascular endothelial growth factor-specific angiogenesis in some cancers. MYL-1402O is a proposed bevacizumab biosimilar.MethodsThe primary objective of this single-center, randomized, double-blind, three-arm, parallel-group, phase 1 study in healthy male volunteers was to evaluate bioequivalence of MYL-1402O to EU and US-reference bevacizumab, and EU-reference bevacizumab to US-reference bevacizumab. The primary pharmacokinetic parameter was area under the serum concentration–time curve from 0 extrapolated to infinity (AUC0–∞). Pharmacokinetic parameters were analyzed using general linear models of analysis of variance. Secondary endpoints included safety and tolerability.ResultsOf 111 enrolled subjects, 110 were included in the pharmacokinetic analysis (MYL-1402O, n = 37; EU-reference bevacizumab, n = 36; US-reference bevacizumab, n = 37). Bioequivalence was demonstrated between MYL-1402O and EU-reference bevacizumab, MYL-1402O and US-reference bevacizumab, and between EU- and US-reference bevacizumab where least squares mean ratios of AUC0–∞ were close to 1, and 90% CIs were within the equivalence range (0.80–1.25). Secondary pharmacokinetic parameters (AUC from 0 to time of last quantifiable concentration [AUC0–t], peak serum concentration [Cmax], time to Cmax, elimination rate constant, and elimination half-life) were also comparable, with 90% CIs for ratios of AUC0–t and Cmax within 80–125%. Treatment-emergent adverse events were similar across all three treatment groups and were consistent with clinical data for bevacizumab.ConclusionMYL-1402O was well tolerated and demonstrated pharmacokinetic and safety profiles similar to EU-reference bevacizumab and US-reference bevacizumab in healthy male volunteers. No new significant safety issues emerged (ClinicalTrials.gov, NCT02469987; ClinicalTrialsRegister.eu EudraCT, 2014-005621-12; June 12, 2015).

Brief High Oxygen Concentration Induces Oxidative Stress in Leukocytes and Platelets: A Randomized Cross-over Pilot Study in Healthy Male Volunteers.

Supplemental oxygen is administered routinely in the clinical setting to relieve or prevent tissue hypoxia, but excessive exposure may induce oxidative damage or disrupt essential homeostatic functions. It is speculated that oxidative stress in leukocytes and platelets may contribute to vascular diseases by promoting inflammation and cell aggregation. In this pilot study 30 healthy male volunteers (18-65 years) were exposed to high oxygen concentration (non-rebreather mask, 8 L/min, 100% O2) and synthetic air (non-rebreather mask, 8 L/min, 21% O2) in a cross-over design for 20 min at a 3-week interval. Venous blood samples were obtained at baseline and 1, 3, and 6 h postintervention. Primary outcome was generation of reactive oxygen species in leukocytes as measured by the redox-sensitive fluorescent dye dihydrorhodamine 123. Additional outcomes were oxidative stress in platelets and platelet aggregation as measured by thromboelastography (ROTEM) and Multiplate analyses. High oxygen exposure induced oxidative stress in leukocytes as evidenced by significantly higher mean fluorescence intensity (MFI) compared with synthetic air at 3 h postintervention (47% higher, P = 0.015) and 6 h postintervention (37% higher, P = 0.133). Oxidative stress was also detectable in platelets (33% higher MFI in comparison with synthetic air at 6 h, P = 0.024; MFI 20% above baseline at 3 h, P  = 0.036; 37% above baseline at 6 h, P = 0.002). ROTEM analyses demonstrated reduced mean clotting time 1 h postintervention compared with baseline (-4%, P = 0.049), whereas there were no significant effects on other surrogate coagulation parameters. Clinically relevant oxygen exposure induces oxidative stress in leukocytes and platelets, which may influence the immune and clotting functions of these cells.

Evaluation of a Pan-Lysyl Oxidase Inhibitor, Pxs-5505, in Myelofibrosis: A Phase I, Randomized, Placebo Controlled Double Blind Study in Healthy Adults

BACKGROUND: Myeloproliferative neoplasms (MPNs) are clonal stem cell neoplasms characterized by terminal expansion of the myeloid cell lineage and include essential thrombocythemia (ET), polycythemia vera (PV), and myelofibrosis (MF). MF carries the worst prognosis and is characterized by reactive bone marrow fibrosis. Currently bone marrow transplant is the only known therapy that can reverse fibrosis and alter the disease course. Lysyl oxidases (LOX, LOXL1-4) are copper amine oxidase enzymes that facilitate the cross-linking of collagen and elastin through deamination and oxidization of lysine residues, yielding highly reactive aldehydes. This is essential for fibrotic tissue formation. An earlier study identified an important role for LOX in the development of MF in mice (Eliades et al, J. Biol. Chem. 2011; PMID: 21665949). Furthermore, small molecule pan-LOX inhibitors reduced spleen size and bone marrow fibrosis in mouse models of MF (Leiva et al, Int J. Hemat. 2019; PMID: 31637674). This provides clinical rationale for the use of pan-lysyl oxidase inhibition in MF. A Phase 1 study was conducted to establish the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of PXS-5505, a pan-lysyl oxidase inhibitor. Plasma levels of LOX and LOXL2 were investigated in a separate cohort of MPN patients, with the ultimate goal to develop PXS-5505-based therapy in MF patients. METHODS: PXS-5505 was dosed orally in a Phase I, randomized, placebo-controlled, single ascending (Part A) and multiple ascending dose (Part B) double-blind study in healthy male volunteers. Plasma LOX and LOXL2 levels were also measured in a separate cohort of MPN patients using ELISA-based Single Molecule Array technology (Simoa; Quanterix). RESULTS: Forty subjects were enrolled in Part A and 16 were enrolled in Part B. In Part A, there were 5 cohorts consisting of 8 subjects (6 active, 2 placebo) with doses of 10, 50, 100, 200 or 300 mg administered once. In Part B, there were 2 cohorts of 8 subjects each (6 active, 2 placebo) at doses of 100 or 200 mg daily for 14 days. There were no significant treatment-related adverse events. Mean age in Part A was 32.0 years (SD 11.14) and 32.1 years (SD 12.14) in Part B. Cmax and AUC increased linearly across the dose range of 10 to 300 mg for single dose administration. In multiple dosing at 200 mg daily, Cmax was 916 ng/mL and AUC0-24 was 7421 hr*ng/mL on Day 14, with median Tmax of 1 hour and t1/2 of 7 hours. When measured in plasma, LOX was dose-dependently inhibited and achieved very strong inhibition (median 80%) with a 200 mg dose around Tmax. The 300 mg dosing did not significantly increase inhibition. Multiple daily doses of 100-200 mg resulted in 60-70% and 50-60% inhibition of plasma LOX at 12 and 24 hours. Average LOX plasma levels were 3.61 ng/mL (range: 3.20-13.42 ng/mL; SD: 2.92 ng/mL). We measured plasma LOX and LOXL2 levels in a separate MPN cohort of 9 ET, 8 PV, and 13 MF patients (mean age 61.4, range:24-84, 65% males). LOXL2 levels were higher in MF (mean 415 pg/mL) compared to ET (mean 209 pg/mL) and PV (mean 322 pg/ml), although this was not significant. However, LOXL2 levels in all MPN patients (mean 333 pg/mL) were significantly higher than LOXL2 levels in normal controls (mean 152 pg/mL, p&amp;lt;0.01). There were no significant differences in LOX levels in the two groups. DISCUSSION: PXS-5505 demonstrated an excellent safety profile and was well tolerated in healthy human subjects. PK/PD properties are consistent with preclinical data and support once or twice daily &amp;gt;100 mg dosing over 14 days. PXS-5505 achieves long-lasting, strong inhibition of lysyl oxidases. Plasma LOXL2 levels are higher in MF patients compared to healthy controls, and we found no significant disease associations of LOX or LOXL2 among MPN subtypes in our small cohort. LOXL2 is likely a more sensitive MF biomarker as it is present at low concentrations in the blood, while LOX is constantly produced from major organs making detection due to disease more difficult. Based on previous mouse studies, it is possible that LOX levels would be higher in MF patients when compared to age-matched controls, which we will investigate further. We will open a Phase IB/II study of PXS-5505 in MF patients resistant to ruxolitinib. Disclosures Neuberg: Madrigak Pharmaceuticals: Current equity holder in publicly-traded company; Celgene: Research Funding; Pharmacyclics: Research Funding. Ravid:Pharmaxis: Research Funding. Jarolimek:Pharmaxis Ltd: Current Employment. Charlton:Pharmaxis Ltd: Current Employment. Hobbs:Novartis: Honoraria; Constellation: Honoraria, Research Funding; Jazz: Honoraria; Celgene/BMS: Honoraria; Merck: Research Funding; Incyte: Research Funding; Bayer: Research Funding.

Фармакокинетические особенности силденафила в форме спрея для здоровых мужчин в зависимости от приема пищи

In order to evaluate the bioequivalence and benefits of a new dosage form of the type 5 phosphodiesterase inhibitor, sildenafil, two open-label studies in healthy male volunteers were carried out.An open, randomized, crossover study to compare the pharmacokinetics after a single dose of sildenafil at a dosage of 50 mg on an empty stomach in a new spray form (test drug) and in a traditional tablet form (comparison drug) on 44 volunteers (18 to 43 years old) was done. To assess the effect of food intake on pharmacokinetics, an open, non-randomized study was conducted on 6 healthy male volunteers (from 23 to 35 years old) who received sildenafil (50 mg) after a meal in timely fashion: 1) spray, under the tongue, without drinking, 2) spray , in the mouth, drinking water and 3) the tablet form, drinking water. For pharmacokinetic analysis, blood was analyzed for 24 hours. Plasma concentration of sildenafil was determined by high performance liquid chromatography with tandem mass spectrometric detection (HPLC/TM/SD). The main parameters were the rate (maximum concentration; Cmax) and the degree of absorption (area under the pharmacokinetic curve "concentration-time" during the observation period; AUC0-t) after a single dose of drugs. In addition, the pharmacokinetic profiles of the bioavailability of sildenafil and its active metabolite, N-desmethyl sildenafil, as well as the safety of the different dosage forms, were evaluated.When comparing taking drugs on an empty stomach, the 90% confidence intervals (CI) of the ratios of the mean Cmax and AUC0-t values of sildenafil were 82-106% and 82-101%, respectively. An earlier achievement of the maximum concentration of sildenafil was detected when taking the test drug compared with the standard form (51 and 62 minutes, respectively, Z-value=-2.25, p-value=0.0244). In addition, it was shown that when taking Viagra after a meal, the determination of sildenafil in plasma was delayed (after 30 minutes) compared to the tested drugs (after 10 minutes), however, significant differences in Tmax between the dosage forms were not seen. In two studies, most adverse events were mild to moderate and resolved uneventfully.The bioavailability of the new dosage form, the sildenafil spray, is equivalent to the traditional form, however, it has an advantage in terms of onset of action. For example, when taking a spray, an earlier achievement of the maximum concentration of sildenafil and an earlier detection of sildenafil in plasma are shown compared to the traditional tablet form.Our results suggest that the new dosage form of sildenafil is a reliable alternative therapeutic option for the treatment of erectile dysfunction.

Results from Drug-Drug Interaction Studies In Vitro and In Vivo Investigating the Effect of Finerenone on the Pharmacokinetics of Comedications.

In vivo studies were performed with the novel, selective, non-steroidal mineralocorticoid receptor antagonist finerenone to assess the relevance of inductive and/or inhibitory effects on cytochrome P450 (CYP) enzymes observed in vitro. CYP isoenzyme-specific substrates were incubated in vitro with finerenone or its metabolites to investigate reversible and irreversible inhibitory as well as inductive potential. Three crossover studies in healthy male volunteers investigated the effects of finerenone (20mg orally) on the pharmacokinetics of the index substrates midazolam (CYP3A4, n = 30), repaglinide (CYP2C8, n = 28) and warfarin (CYP2C9, n = 24). Finerenone caused direct inhibitory effects on CYP activities in vitro in the rank order CYP2C8, CYP1A1 > CYP3A4 > CYP2C9 and CYP2C19, but not on other major CYP isoforms. Moreover, irreversible inhibition of CYP3A4 was observed. The major metabolites of finerenone demonstrated minor reversible inhibition of CYP1A1, CYP2C9 and CYP3A4 with no hint of time-dependent inhibition of any CYP isoform. Calculations from in vitro data according to regulatory guidelines suggested likely inhibition of CYP2C8 and CYP3A4 in vivo, whereas this was not the case for CYP1A1, CYP2C9 and CYP2C19. Furthermore, finerenone and three of its metabolites were inducers of CYP3A4 in vitro with predicted weak-to-moderate in vivo relevance. Studies in healthy volunteers, prompted by these results, demonstrated no effect of finerenone on CYP isoenzymes for which in vitro data had indicated potential inhibition or induction. Administration of finerenone 20mg once daily confers no risk of clinically relevant drug-drug interactions with substrates of cytochrome P450 enzymes.

Development and validation of a method to confirm the exogenous origin of prednisone and prednisolone by GC-C-IRMS.

Prednisone and prednisolone are two anti-inflammatory steroidal drugs listed by the World Anti-Doping Agency (WADA) within the class of glucocorticoids, which are prohibited "in competition" and when administered systemically. Their presence in collected urine samples may be attributed, if no exogenous administration has occurred, to an in situ microbial formation from endogenous steroids. In this work, a gas chromatography coupled to carbon isotope ratio mass spectrometry (GC-C-IRMS) method was developed and validated to distinguish an exogenous origin from an endogenous one. Eight prednisone/prednisolone pharmaceutical preparations commercially available in Italy were analysed to establish an exogenous δ13 C value reference range (-28.96 ± 0.39‰). No more than 25 mL of urine was processed and no derivatization nor intentional steroids structure modifications were performed before the GC-C-IRMS analysis. A first HPLC purification step was set up to isolate the three endogenous reference compounds (ERCs) selected (tetrahydro-11-deoxycortisol (THS), pregnanediol (PD), and pregnanetriol (PT)), while a second LC purification was necessary to separate prednisone from prednisolone. In the GC-C-IRMS analysis, two different GC run methods were set up to guarantee better sensitivity and selectivity for each compound. Both prednisone and prednisolone showed signals (m/z 44) with amplitudes within the method linearity range to a lower urinary concentration of 20 ng/mL (< WADA reporting level, 30 ng/mL). The method was fully validated according to WADA requirements. As a proof of concept, urine samples collected from two excretion studies in healthy male volunteers, after a prednisone or prednisolone administration, were analysed by the proposed method, demonstrating its applicability for the analysis of real samples.

A Study in Healthy Male Volunteers to Test How the Test Medicine GLPG1972 is Taken up by the Body When Given by Mouth and Into the Vein as an Injection

A Study in Healthy Male Volunteers to Test How the Test Medicine GLPG1972 is Taken up by the Body When Given by Mouth and Into the Vein as an Injection

Single Ascending Dose PK, Oral Bioavailability and Food Effect Study in Healthy Male Volunteers

Single Ascending Dose PK, Oral Bioavailability and Food Effect Study in Healthy Male Volunteers

Comparative single-dose bioavailability study of two 10 mg Zolpidem tablet formulations in healthy volunteers

Zolpidem is a hypnotic agent with a chemical structure unrelated to benzodiazepines, barbiturates, pyrrolopyrazines, pyrazolopyrimidines or other drugs with known hypnotic properties. Zolpidem as conventional tablets is used as a hypnotic agent in the short-term management of insomnia, generally for periods not exceeding 7–10 days in duration. The objective of this study was to evaluate and compare the relative bioavailability, and therefore the bioequivalence of Zolpidem 10 mg test formulation versus a reference Zolpidem 10 mg formulation, following a single dose administration under fasting conditions The study was a single center, open, single dose, randomized, two - way crossover study in healthy male volunteers with a wash - out period of one week between study periods. Twenty-eight male healthy volunteers, aged 20-49 years were included into study. Blood samples for determination of zolpidem plasma concentrations were withdraw at 0 (pre-drug administration), 0.33, 0.66, 1, 1.33, 1.66, 2, 2.5, 3, 3.5, 4, 5, 6, 8, 10, 12, 16 and 24 hours post-drug. The zolpidem concentrations in plasma were determined with HPLC, using fluorescence detection. The test formulation of zolpidem, dosed at 10 mg is bioequivalent for primary zolpidem parameters (Cmax, AUC0-t and AUC0-∞) to the reference formulation after a single oral administration of 10 mg zolpidem. Both medications are well tolerated with no serious adverse events. Thus, in view of the clinical use, both formulations are exchangeable without restrictions. Keywords: Zolpidem, bioavailability, bioequivalence study, single-dose

Comparative single-dose bioavailability study of two 500 mg clarithromycin tablet formulations in healthy volunteers under fasting condition

Clarithromycin is a semi-synthetic macrolide antibiotic, chemically 6-0-methylerythromycin, formulated as immediate-release tablets, extended-release tablets, and granules for oral suspension. The objective of this study was to evaluate and compare the relative bioavailability, and therefore the bioequivalence of Clarithromycin 500 mg test formulation versus a reference Klacid® forte 500 mg formulation, following a single dose administration under fasting conditions. The study was a single center, open, single dose, randomized, two-way crossover study in healthy male volunteers, with a wash-out period of one week between study periods. Twenty-four male healthy volunteers, aged 18-49 years were included into study. Blood samples for determination of clarithromycin and 14-OH clarithromycin concentrations were withdrawn at zero (pre-drug administration), 0.33, 0.66, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 8, 12, 24 and 36 hours post-drug administration. The determination of clarithromycin and 14-OH clarithromycin concentrations in plasma was performed using validated LC/MS/MS method and internal standardization after liquid/liquid extraction with methyl t-butyl ether. The test formulation of clarithromycin, dosed at 500 mg is bioequivalent for primary clarithromycin and 14-OH clarithromycin parameters (Cmax, AUC0-t and AUC0-∞) to the reference formulation after a single oral administration of 500 mg clarithromycin. Both medications were well tolerated with no serious adverse events. Thus, in view of the clinical use, both formulations are exchangeable without restrictions. Keywords: clarithromycin, 14-OH clarithromycin, bioavailability, bioequivalence study, single-dose

Safety, Pharmacokinetics, and Pharmacodynamics of ME-401, an Oral, Potent, and Selective Inhibitor of Phosphatidylinositol 3-Kinase P110δ, Following Single Ascending Dose Administration to Healthy Volunteers

PurposeME-401 is a novel selective inhibitor of phosphatidylinositol 3 kinase p110δ, an enzyme often found overexpressed and overactive in B-cell malignancies. The current study was performed to assess the safety, tolerability, pharmacokinetics, and pharmacodynamics of single ascending oral doses of ME-401 in healthy volunteers. MethodsThis analysis was an open-label, nonrandomized study in healthy male volunteers. Three sequential groups were dosed. Each group received single doses of ME-401 on two occasions; the doses tested ranged from 10 to 150 mg. Blood was drawn at various time points to analyze plasma concentrations of ME-401 and inhibition of basophil activation, a marker of phosphatidylinositol 3 kinase p110δ inhibition. FindingsFifteen subjects received a single dose of ME-401 on two occasions. Three adverse events that were considered possibly related to the study drug were reported: one event of pain, one event of headache, and one event of upper abdominal pain. ME-401 exhibited dose proportionality up to 60 mg, and supra-proportional increases in exposure were observed above doses of 60 mg. In addition, there was a dose-proportional increase in the inhibition of basophil activation up to 60 mg. Mean t1/2 ranged from 9.36 to 29.23 hours across the dose range. A 60 mg dose of ME-401 approached 90% inhibition of basophil activation, and thereafter no further increase to the percent inhibition of basophil activation was observed for higher doses. Once-daily dosing of 60 mg ME-401 was forecasted to result in trough plasma levels exceeding the concentration needed for 90% inhibition of basophil activation. ImplicationsThis first-in-human study showed that ME-401 was well tolerated after single doses up to 150 mg. Pharmacologic activity was confirmed after administration of single ascending oral doses of 10 to 150 mg. ME-401 60 mg, administered once daily, was selected as the starting dose for patient studies. ClinicalTrials.gov identifier: NCT02521389.

Simultaneous analysis of olanzapine, fluoxetine, and norfluoxetine in human plasma using liquid chromatography-mass spectrometry and its application to a pharmacokinetic study

Adjunctive therapy with olanzapine and fluoxetine has been shown to be beneficial in treatment-resistant depression and the depressive phase of bipolar disorder. Consensus guidelines issued by the Arbeitsgemeinschaft für Neuropsychopharmakologie und Pharmakopsychiatrie strongly recommend that patients taking olanzapine undergo therapeutic drug monitoring (TDM), and suggest that TDM is useful for patients taking fluoxetine. The aim of the current study was to develop and validate a sensitive, practical, and robust liquid chromatography-tandem mass spectrometry method (LC-MS/MS) for simultaneous determination of olanzapine, fluoxetine, and norfluoxetine in human plasma for routine TDM. Simple liquid-liquid extraction using ethyl acetate was used to extract olanzapine, fluoxetine, and norfluoxetine from 200 μL of pre-basified human plasma. Analytes were separated on an Agilent Eclipse Plus C18 column (4.6 × 100 mm, 5 μm) eluted with a mobile phase consisting of methanol:20 mM ammonium formate buffer (82.5:17.5, v/v), and then quantified using an electrospray ionization source operated in positive ion multiple reaction monitoring mode. The linear range for the analytes was 0.2–25 ng/mL, covering the vast majority of levels encountered in real-life samples. A weighting factor of 1/x2 best fit the calibration curves. The mean internal standard-normalized matrix effects for all analytes were 99.5%–110%. The extraction recoveries were 75%–85% for olanzapine and olanzapine‑d3, and 58%–69% for fluoxetine, norfluoxetine, and their deuterated internal standards. Accuracy and precision values also met the acceptance criteria. The stability assessments showed that QC samples containing the three analytes were stable for at least 1 d at room temperature, 21 d at −70 °C, and through three freeze-thaw cycles. Post-preparation storage for 2 d in the autosampler did not cause obvious degradation of the investigated compounds. This validated high performance LC-MS/MS method was successfully applied to a pharmacokinetic study in healthy male volunteers.

Pharmacokinetic interactions and tolerability of rosuvastatin and ezetimibe: an open-label, randomized, multiple-dose, crossover study in healthy male volunteers.

PurposeRosuvastatin is a synthetic 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor that effectively reduces low-density lipoprotein cholesterol levels. However, statin monotherapy does not always achieve acceptable low-density lipoprotein cholesterol levels in patients with severe hypercholesterolemia. Ezetimibe, a selective cholesterol-absorption inhibitor, is approved for use as a monotherapy or combination therapy with 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors for patients with hypercholesterolemia. The aim of this study was to examine the pharmacokinetics (PKs) of drug interactions between rosuvastatin and ezetimibe, and the tolerability of combined administration in healthy Korean male volunteers.Subjects and methodsHealthy subjects (n=24) were randomly allocated to 3 treatment groups: rosuvastatin (20 mg) alone, ezetimibe (10 mg) alone, and rosuvastatin (20 mg) plus ezetimibe (10 mg). The drugs were taken once every 24 hours over a period of 10 days. Blood samples were collected to analyze steady-state PKs.ResultsAll adverse events observed during the study were mild, and the frequency was no higher for combined administration than for mono administration. For rosuvastatin, the steady-state mean ratios (90% CI) of the combined over the single dose were 1.076 (1.019–1.136) for AUCτ,ss and 1.099 (1.003–1.204) for concentration at steady-state, respectively. In the case of free and total ezetimibe, the steady-state ratios of AUCτ,ss and concentration at steady-state were 1.131 (1.051–1.218) and 1.182 (1.038–1.346), and 1.055 (0.969–1.148) and 0.996 (0.873–1.135), respectively.ConclusionCombined administration of rosuvastatin and ezetimibe was well tolerated. No clinically significant PK interactions between rosuvastatin and ezetimibe were observed when the 2 drugs were administered concomitantly.

Pharmacokinetics comparison of solifenacin tartrate and solifenacin succinate: a randomized, open-label, single-dose, 2-way crossover study in healthy male volunteers.

Solifenacin is a muscarinic antagonist indicated for the treatment of overactive bladder with symptoms. Solifenacin tartrate is a newly developed salt formulation of solifenacin. This study compared the pharmacokinetic and safety properties after single-dose administration of solifenacin tartrate (test formulation) and solifenacin succinate (reference formulation) in healthy male volunteers. A total of 36 subjects were enrolled in this randomized, open-label, single-dose, two-way crossover study. During each treatment period, subjects received the test formulation or reference formulation. Plasma samples were collected at pre-dose and at 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 24, 48 and 72 hours post-dose. Safety was assessed by adverse events, physical examinations, laboratory assessments, 12-lead electrocardiograms, and vital signs. Thirty-three subjects completed the study and were included in the pharmacokinetic analysis. The mean (standard deviation) values of AUClast for the test and reference formulations were 486.98 (138.47) and 469.07 (128.29) h·ng/mL, respectively. The mean (standard deviation) values of Cmax for the test and reference formulations were 14.66 (3.85) and 14.10 (3.37) ng/mL, respectively. The 90% confidence intervals for AUClast and Cmax were 0.9702 to 1.1097 and 0.9779 to 1.0993, respectively. All adverse events were mild or moderate, and there were no serious adverse events. The pharmacokinetic properties of solifenacin tartrate were similar to those of solifenacin succinate and met the acceptance criteria for bioequivalence. Both formulations were safe, and no significant difference was observed in the safety assessments of the formulations.

Pharmacokinetic Bioequivalence Study of Two Formulations of Teriflunomide in Healthy Male Volunteers under Fasting Conditions

A generic formula containing 14 mg of teriflunomide (Terflimida® test formulation) in oral coated tablets was compared to the reference product (Aubagio®) in a pharmacokinetic, open label, two-periods, two sequences, two-way crossover; block randomized single dose study in healthy male volunteers under fasting conditions.The statistical analysis of the pharmacokinetic data obtained in this study showed that the Teriflunomide formulations: Terflimida® coated tablets 14 (test formulation) and Aubagio® 14 mg coated tablets (reference formulation), were bioequivalent regarding the rate (Cmax) and the extent of absorption (AUC0-72), under fasting conditions. The Teriflunomide treatments (TEST and REFERENCE formulations), administered orally in single dose, to male healthy volunteers, under fasting conditions, were very well tolerated by all the participating subjects.

Pharmacokinetics of intravenous pan-class I phosphatidylinositol 3-kinase (PI3K) inhibitor [14C]copanlisib (BAY 80-6946) in a mass balance study in healthy male volunteers

PurposeTo determine the pharmacokinetics of radiolabeled copanlisib (BAY 80-6946) in healthy male volunteers and to investigate the disposition and biotransformation of copanlisib.MethodsA single dose of 12 mg copanlisib containing 2.76 MBq [14C]copanlisib was administered as a 1-h intravenous infusion to 6 volunteers with subsequent sampling up to 34 days. Blood, plasma, urine and feces were collected to monitor total radioactivity, parent compound and metabolites.ResultsCopanlisib treatment was well tolerated. Copanlisib was rapidly distributed throughout the body with a volume distribution of 1870 L and an elimination half-life of 52.1-h (range 40.4–67.5-h). Copanlisib was the predominant component in human plasma (84% of total radioactivity AUC) and the morpholinone metabolite M1 was the only circulating metabolite (about 5%). Excretion of drug-derived radioactivity based on all 6 subjects was 86% of the dose within a collection interval of 20–34 days with 64% excreted into feces as major route of elimination and 22% into urine. Unchanged copanlisib was the main component excreted into urine (15% of dose) and feces (30% of dose). Excreted metabolites (41% of dose) of copanlisib resulted from oxidative biotransformation.ConclusionsCopanlisib was eliminated predominantly in the feces compared to urine as well as by hepatic biotransformation, suggesting that the clearance of copanlisib would more likely be affected by hepatic impairment than by renal dysfunction. The dual mode of elimination via unchanged excretion of copanlisib and oxidative metabolism decreases the risk of clinically relevant PK-related drug–drug interactions.