Pooled Aquablation Results for American Men with Lower Urinary Tract Symptoms due to Benign Prostatic Hyperplasia in Large Prostates (60–150 cc)

Introduction

To present short-term safety and efficacy data of men with lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH) treated with Aquablation.

Methods

Men with LUTs secondary to BPH (60–150 cc) underwent Aquablation treatment from February 2016 to December 2017 across 17 investigational sites in the USA from two contemporary investigational device exemption (IDE) studies called WATER (NCT02505919) and WATER II (NCT03123250).

Results

One hundred seven males with mean age of 67.3?±?6.5 years were treated with Aquablation; mean prostate volume was 99.4?±?24.1 cc. The pooled results show that large prostates have an average procedure time of less than 36 min and discharge on average 1.6?±?1 days. The IPSS decreased by 16.7?±?8.1 points at 3 months and Q_max increased by 11.2?±?12.4 ml/s. The Clavien-Dindo (CD) grade 2 or higher event rate at 3 months was 29%. A non-hierarchical breakdown for CD events yielded 18% grade 2 and 19% grade 3 or higher.

Conclusion

Men with LUTS secondary to BPH (60–150 cc) in a pooled analysis were treated safely and effectively with Aquablation up to 3 months postoperatively.

Trial Registration

ClinicalTrials.gov identifiers, NCT02505919 and NCT03123250.

Funding

PROCEPT BioRobotics.

     

Pharmacokinetics of a Single Dose of Azilsartan in Pediatric Patients: A Phase 3, Open-Label,Multicenter Study

Introduction

Azilsartan is an angiotensin II receptor blocker indicated for the treatment of patients with hypertension. The efficacy and safety of azilsartan are established in adults, but have not been evaluated in pediatric patients, nor has its pharmacokinetic profile been determined in pediatric patients.

Methods

In this phase 3, open-label, multicenter study, we investigated the pharmacokinetics and safety of single doses of azilsartan in six Japanese patients with hypertension, aged 9–14 years. The dose of azilsartan was 5 mg for three patients weighing less than 50 kg, with mean body weight at baseline of 27.5 kg, and 10 mg for three patients weighing at least 50 kg, with mean body weight at baseline of 65.9 kg.

Results

Mean maximum plasma concentration (C_max) of azilsartan was 888.3 and 831.3 ng/mL and median time to maximum concentration (T_max) of unchanged azilsartan was 3.0 and 4.0 h, in the 5-mg and 10-mg groups, respectively. Mean areas under the plasma concentration–time curve (AUC) from 0–24 h post-dose (AUC_0–24) and 0 h to infinity (AUC_0–inf) were 6350.3 and 6635.7 ng h/mL, respectively, in the 5-mg group, and 6871.7 and 7433.3 ng h/mL, respectively, in the 10-mg group. Both doses were well tolerated; no treatment-emergent adverse events considered to be related to azilsartan occurred during the study.

Conclusion

Our data suggest that pediatric patients weighing less than 50 kg may have? approximately 2-fold greater exposure to azilsartan than those weighing at least 50 kg at the same dose. Exposure to azilsartan in children weighing at least 50 kg is comparable to that in healthy adults at the same dose.

Trial Registration

ClinicalTrials.gov identifier, NCT02451150.

Funding

Takeda Pharmaceutical Co. Ltd.

     

A Randomized Trial Investigating the Pharmacokinetics,Pharmacodynamics, and Safety of Subcutaneous Semaglutide Once-Weekly in Healthy Male Japanese and Caucasian Subjects

Introduction

Semaglutide is a glucagon-like peptide-1 analogue for once-weekly subcutaneous treatment of type 2 diabetes. This trial compared the pharmacokinetics, pharmacodynamics, and safety of semaglutide in Japanese and Caucasian subjects.

Methods

In this single-center, double-blind, parallel-group, 13-week trial, 44 healthy male subjects (22 Japanese, 22 Caucasian) were randomized within each race to semaglutide 0.5 mg (n = 8), 1.0 mg (n = 8), placebo 0.5 mg (n = 3) or 1.0 mg (n = 3). The primary endpoint was semaglutide exposure at steady state [area under the curve (AUC_0–168h)].

Results

Steady-state exposure of semaglutide was similar for both populations: AUC_0–168h estimated race ratio (ERR), Japanese/Caucasian: 0.5 mg, 1.06; 1.0 mg, 0.99; maximum concentration (C_max) ERR: 0.5 mg, 1.06; 1.0 mg, 1.02. Exposure after the first dose (0.25 mg) was slightly higher in Japanese versus Caucasian subjects (AUC_0–168h ERR 1.11; C_max ERR 1.14). Dose-dependent increases in AUC_0–168h and C_max occurred in both populations. Accumulation was as expected, based on the half-life (t_1/2, ~ 1 week) and dosing interval of semaglutide. Significant body weight reductions were observed with semaglutide 0.5 mg and 1.0 mg in Japanese (both p ≤ 0.05) and Caucasian (both p ≤ 0.05) subjects versus placebo. No new safety issues were identified.

Conclusions

The pharmacokinetic, pharmacodynamic, and safety profiles of semaglutide were similar in Japanese and Caucasian subjects, suggesting that no dose adjustment is required for the clinical use of semaglutide in Japanese subjects.

Funding

Novo Nordisk A/S, Denmark.

Trial registration

ClinicalTrials.gov identifier NCT02146079. Japanese trial registration number JapicCTI-142550.

     

700-nm Zwitterionic Near-Infrared Fluorophores for Dual-Channel Image-Guided Surgery

Purpose

The purpose of this study was to develop a family of 700-nm zwitterionic pentamethine indocyanine near-infrared fluorophores that would permit dual-channel image-guided surgery.

Procedures

Three complementary synthetic schemes were used to produce novel zwitterionic chemical structures. Physicochemical, optical, biodistribution, and clearance properties were compared to Cy5.5, a conventional pentamethine indocyanine now used for biomedical imaging.

Results

ZW700-1a, ZW700-1b, and ZW700-1c were synthesized, purified, and analyzed extensively in vitro and in vivo. All molecules had extinction coefficients ≥199,000 M^?1 cm^?1, emission ≥660 nm, and stability ≥99 % after 24 h in warm serum. In mice, rats, and pigs, ≥80 % of the injected dose was completely eliminated from the body via renal clearance within 4 h. Either alone or conjugated to a tumor targeting ligand, ZW700-1a permitted dual-channel, high SBR, and simultaneous imaging with 800-nm NIR fluorophores using the FLARE® imaging system.

Conclusions

Novel 700-nm zwitterionic NIR fluorophores enable dual-NIR image-guided surgery.

     

A Single-Dose,Crossover-Design Bioequivalence Study Comparing Two Nicotine Gum Formulations in Healthy Subjects

Introduction

Nicotine replacement therapy (NRT) benefits smokers who wish to quit; nicotine gum represents one NRT. New formulations of nicotine gum have been developed to consider consumer preferences and needs. A new mint-flavored nicotine gum with a different texture was developed that may provide a more appealing taste and chewing experience. This study evaluated this new nicotine gum (2 and 4 mg strengths) for bioequivalence versus the original flavor sugar-free nicotine gum at corresponding dosages.

Methods

All subjects randomized in this crossover study received a single dose of all treatments, i.e., 2 and 4 mg doses of test and reference gums, separated by 2–7 days of washout between treatments. Subjects’ maximal plasma nicotine concentration (C_max) and extent of nicotine absorption (AUC_0–t) following the administration of each treatment were calculated from plasma nicotine concentrations. Ratios of test/reference for C_max and AUC_0–t were calculated to evaluate bioequivalence between the two products.

Results

Both 2 and 4 mg doses of the new mint-flavored nicotine gum were bioequivalent to the dose-matched reference product as determined by the ratio of the geometric means and their 90% confidence intervals for C_max and AUC_0–t as well as secondary pharmacokinetic parameters. The safety profiles of the test and reference gums were similar; all treatments were well tolerated.

Conclusions

A new mint-flavored nicotine gum with modified taste and texture is bioequivalent to the original flavor sugar-free nicotine gum at both the 2 and 4 mg dosage strengths and has a similar safety profile.

Funding

GlaxoSmithKline.

Trial Registration

ClinicalTrials.gov identifier NCT01847443.

     

Correlation Between Aquaporin 4 Expression and Different DWI Parameters in Grade I Meningioma

Purpose

Diffusion-weighted imaging (DWI) measures water diffusion in biological tissues. Cellular water transport depends on aquaporins (AQPs). The expression of aquaporins might differ in several pathologic disorders. Therefore, the aim of this study was to evaluate the associations between AQP4 expression and different DWI parameters in meningioma.

Procedures

Twenty-three patients with meningioma grade I were included in this retrospective study. DWI was obtained with three b values (0; 500; 1000) using a 1.5-T device. ADC_mean, ADC_min, ADC_max, and true diffusion coefficients (D) were obtained in every patient. Aquaporin 4 expression was quantified immunohistochemically in four immunoreactivity levels.

Results

The estimated DWI parameters (mean value ± standard deviation, 10^?3 mm² s^?1) of the tumors were as follows: ADC_min 0.67 ± 0.16, ADC_mean 0.94 ± 0.23, ADC_max 1.29 ± 0.50, and D 0.65 ± 0.23. The mean level of the AQP4 expression was 2.02 ± 0.75 points. A statistically significant correlation between AQP4 expression and ADC_max was identified (r = 0.508, p = 0.013). No significant correlations between AQP4 and other DWI parameters were found.

Conclusions

A clear correlation between AQP4 expression and ADC_max values in grade I meningioma was identified. There were no significant correlations between AQP4 expression and other DWI parameters, such as ADC_min, ADC_mean, and D.

     

Effects of Ketoconazole on the Pharmacokinetics of Mifepristone,a Competitive Glucocorticoid Receptor Antagonist,in Healthy Men

Introduction

Mifepristone, a competitive glucocorticoid receptor antagonist approved for Cushing syndrome, and ketoconazole, an antifungal and steroidogenesis inhibitor, are both inhibitors of and substrates for cytochrome P450 (CYP3A4). This study evaluated the pharmacokinetic effects of concomitant ketoconazole, a strong CYP3A4 inhibitor, on mifepristone.

Methods

In an open-label, two-period, single-center study, healthy adult men received mifepristone 600 mg orally daily for 12 days (period 1) followed by mifepristone 600 mg daily plus ketoconazole 200 mg orally twice daily for 5 days (period 2). Serial pharmacokinetic blood samples were collected predose and over 24 h postdose on days 12 (period 1) and 17 (period 2). A cross-study comparison (using data on file) further examined whether systemic exposure to mifepristone plus ketoconazole exceeded the exposure following mifepristone 1200 mg orally administered for 7 days.

Results

Sixteen subjects were enrolled and 14 completed the study. Concomitant administration with ketoconazole increased the systemic exposure to mifepristone, based on geometric least squares mean ratios, by 28% for C _max and 38% for AUC_0–24. This increase was 85% and 87% of the exposure observed following mifepristone’s highest label dose of 1200 mg/day for C _max and AUC_0–24, respectively. Adverse events (AEs) were reported in 56.3% (9/16) of subjects during administration of mifepristone alone and in 57.1% (8/14) during combination with ketoconazole. No serious AEs were reported.

Conclusion

Systemic exposure to mifepristone increased following multiple doses of mifepristone 600 mg daily plus ketoconazole 200 mg twice daily. Little to no increase in AEs occurred. Dose adjustment of mifepristone may be needed when given with ketoconazole.

Funding

Corcept Therapeutics.

     

Outcomes Following Implantation of Two Second-Generation Trabecular Micro-Bypass Stents in Patients with Open-Angle Glaucoma on One Medication: 18-Month Follow-Up

Introduction

The study objective was to evaluate the intraocular pressure (IOP) and medication-lowering effect of 2 second-generation trabecular micro-bypass stents in eyes with open-angle glaucoma (OAG) on one preoperative medication.

Methods

Fifty-seven qualified phakic eyes with OAG on 1 medication, preoperative medicated IOP of 18–30 mmHg, and preoperative unmedicated (post-washout) IOP of 22–38 mmHg underwent implantation of 2 second-generation trabecular micro-bypass stents in a standalone procedure. Evaluations included IOP, best-corrected visual acuity, medication use, fundus and slit lamp examinations, visual field, cup to disc ratio, pachymetry, and complications and interventions. Subjects have been followed for 18 months, and follow-up is ongoing.

Results

At Month 12 postoperative, 100% of eyes had achieved an IOP reduction ≥20% (100% had IOP ≤18 mmHg and 67% had IOP ≤15 mmHg) without medication versus preoperative unmedicated IOP, and 75% had IOP reduction ≥20% without medication versus preoperative medicated IOP. The Month 12 mean unmedicated IOP had decreased by 42%, to 14.2 ± 1.9 mmHg vs 24.4 ± 1.3 mmHg preoperatively, and this reduction was maintained through 18 months (14.4 ± 2.1 mmHg). A high safety profile was observed.

Conclusion

In this prospective, open-label, single-arm study, the standalone implantation of two second-generation trabecular micro-bypass stents in OAG patients on 1 preoperative medication resulted in IOP reduction to ≤15 mmHg and elimination of medication through 18 months, with favorable safety.

Trial Registration

ClinicalTrials.gov identifier, NCT02868190.

Funding

Glaukos Corporation, San Clemente, CA.

     

Comparison of the Systemic and Local Pharmacokinetics of Clonidine Mucoadhesive Buccal Tablets with Reference Clonidine Oral Tablets in Healthy Volunteers: An Open-Label Randomised Cross-Over Trial

Introduction

The clonidine mucoadhesive buccal tablet (MBT) is a novel delivery system resulting in high and sustained concentrations of clonidine in the oral cavity. In a phase II clinical trial, clonidine MBT reduced the incidence of severe oral mucositis (OM) compared to placebo in head and neck cancer patients undergoing chemoradiation. This study compared the pharmacokinetics (PK), safety and tolerability of clonidine MBT with a reference oral tablet (OT).

Methods

This was a randomised, three-period, single-dose crossover study in 36 healthy subjects aged 18–50 years. Eligibility was assessed within 14 days of the first dose. IMP was administered in the fasted state on day 1 of each treatment period. PK samples were collected up to 24 h (saliva)/96 h (blood) for measurement of the clonidine concentration. Safety and tolerability were evaluated at specified times throughout the study. A washout period of at least 7 days was observed between administrations.

Results

Clonidine MBT (50 and 100 µg) applied to the upper gum resulted in a dose-proportional increase in saliva (C _max and AUC_0–t ) and plasma (C_max and AUC_0–inf) clonidine levels. Clonidine MBT was considered to mimic a continuous release of clonidine in plasma, significantly decreasing the C _max and AUC and increasing the T _max when compared with the reference clonidine HCl tablets. Clonidine MBT exhibited high and prolonged concentrations in saliva where concentrations with the clonidine HCl tablet were negligible. Clonidine MBT exhibited a favourable safety profile with significantly fewer subjects reporting AEs (dry mouth and fatigue) and a reduction in blood pressure when compared to the reference clonidine HCl tablets.

Conclusion

Clonidine MBT is well tolerated and exhibits proportional saliva and plasma PK over the 50–100-µg dose level. The MBT results in higher saliva concentrations and lower systemic exposure than OT, which was associated with a trend towards fewer adverse events and less dry mouth, fatigue and hypotensive effect.

Funding

Onxeo SA.

Trial Registration

ClinicalTrials.gov identifier, NCT02548806.

     

Severe hypercapnia and outcome of mechanically ventilated patients with moderate or severe acute respiratory distress syndrome

Purpose

To analyze the relationship between hypercapnia developing within the first 48 h after the start of mechanical ventilation and outcome in patients with acute respiratory distress syndrome (ARDS).

Patients and methods

We performed a secondary analysis of three prospective non-interventional cohort studies focusing on ARDS patients from 927 intensive care units (ICUs) in 40 countries. These patients received mechanical ventilation for more than 12 h during 1-month periods in 1998, 2004, and 2010. We used multivariable logistic regression and a propensity score analysis to examine the association between hypercapnia and ICU mortality.

Main outcomes

We included 1899 patients with ARDS in this study. The relationship between maximum PaCO₂ in the first 48 h and mortality suggests higher mortality at or above PaCO₂ of ≥50 mmHg. Patients with severe hypercapnia (PaCO₂ ≥50 mmHg) had higher complication rates, more organ failures, and worse outcomes. After adjusting for age, SAPS II score, respiratory rate, positive end-expiratory pressure, PaO₂/FiO₂ ratio, driving pressure, pressure/volume limitation strategy (PLS), corrected minute ventilation, and presence of acidosis, severe hypercapnia was associated with increased risk of ICU mortality [odds ratio (OR) 1.93, 95% confidence interval (CI) 1.32 to 2.81; p = 0.001]. In patients with severe hypercapnia matched for all other variables, ventilation with PLS was associated with higher ICU mortality (OR 1.58, CI 95% 1.04–2.41; p = 0.032).

Conclusions

Severe hypercapnia appears to be independently associated with higher ICU mortality in patients with ARDS.

Trial registration

Clinicaltrials.gov identifier, NCT01093482.

     

Pivotal Bioequivalence Study of Clopacin<Superscript>®</Superscript>, a Generic Formulation of Clopidogrel 75 mg Film-Coated Tablets

Introduction

Clopacin^® (Acino Pharma AG) is a proprietary, besylate salt and lactose-free formulation of the widely-used anti-platelet treatment, clopidogrel. This study aimed to evaluate the bioequivalence of Clopacin^® with the originator as reference drug, using a guideline-compliant trial design: open-labeled, randomized, single-dose (clopidogrel 75 mg tablet), two-period, crossover trial in 48 healthy male volunteers, with a 7 day wash-out period.

Methods

Plasma samples were collected at intervals and extracted before quantifying clopidogrel concentrations using a fully validated LC–MS/MS method. Bioequivalence of Clopacin^® and the reference drug was established by comparison of the primary pharmacokinetic parameters, C _max, AUC_0–t, and AUC_0–∞.

Results

The parameter values were similar for the two products (analysis of variance) and provided Clopacin/reference ratios (least squares means) of >90% and 90% confidence intervals (CIs 84.64–105.50%, 90.43–111.22%, 88.75–110.71%, respectively) that were well within the limits set for defining bioequivalence, according to international guidelines. The respective Clopacin^® and reference drug values for mean time to maximal plasma clopidogrel concentration (t _max) were 0.83 and 0.91 h, and for terminal elimination half-life were 3.99 and 3.51 h. The intra-subject coefficients of variability for maximal plasma clopidogrel concentration (C _max), area under the plasma clopidogrel concentration versus time curve, at 48 h (AUC_0–t) and extrapolated to infinity (AUC_0–∞) were 32.2%, 30.2%, and 28.9% (least square means), respectively, and the respective power values were 99.5%, 97.1%, and 95.3%.

Conclusion

This bioequivalence study provided robust clopidogrel pharmacokinetic data that established the bioequivalence of Clopacin^® and the reference originator drug.

Funding

Acino Pharma AG (formerly Cimex AG)

     

Efficacy and Safety of Vedolizumab in Ulcerative Colitis and Crohn’s Disease Patients Stratified by Age

Introduction

The efficacy and safety of vedolizumab, a gut-selective α₄β₇ integrin antibody, were demonstrated in the GEMINI 1 and GEMINI 2 clinical trials of adults aged 18–80 years. We investigated the efficacy and safety of vedolizumab in patients stratified by age from the GEMINI trials.

Methods

Safety and efficacy, including clinical response, clinical remission, and corticosteroid-free remission, at week 6 and/or 52 were determined post hoc in patients aged <35, 35 to <55, and ≥55 years.

Results

At baseline, 353, 412, and 130 ulcerative colitis (UC) and 582, 443, and 90 Crohn’s disease (CD) patients were aged <35, 35 to <55, and ≥55. Of these patients, 56 were aged ≥65 years (UC: 33, CD: 23). Trends favoring vedolizumab over placebo were observed for most efficacy endpoints irrespective of patient age; some variability between subgroups was observed. Safety profiles of vedolizumab and placebo were similar in all age groups. Vedolizumab-treated patients aged ≥55 had the lowest incidence of serious infections (0.9 per 100 person–years) and adverse events leading to hospitalization (14.8 per 100 person–years). There were no age-related differences in the incidence of adverse hematological events, malignancy, or death.

Conclusions

The safety and efficacy of vedolizumab in patients with UC or CD were similar for all age groups. The number of patients in the oldest age group in these analyses was small; thus further studies of vedolizumab in larger cohorts of elderly patients are warranted.

Funding

Millennium Pharmaceuticals, Inc. (d/b/a Takeda Pharmaceuticals International Co.).

     

Nonclinical Evaluation of PF-06438179: A Potential Biosimilar to Remicade<Superscript>®</Superscript> (Infliximab)

Introduction

PF-06438179, a potential biosimilar to Remicade^® (infliximab, Janssen Biotech, Inc.), is a chimeric mouse–human monoclonal antibody targeting human tumor necrosis factor alpha (TNF).

Methods

Analytical (small subset reported here) and nonclinical studies compared the structural, functional, and in vivo nonclinical similarity of PF-06438179 with Remicade sourced from the United States (infliximab-US) and/or European Union (infliximab-EU).

Results

The peptide map profiles were superimposable, and peptide masses were the same, indicating identical amino acid sequences. Data on post-translational modifications, biochemical properties, and biological function provided strong support for analytical similarity. Administration of a single intravenous (IV) dose (10 or 50 mg/kg) of PF-06438179 or infliximab-EU to male rats was well tolerated. There were no test article-related clinical signs or effects on body weight or food consumption. Systemic exposures [maximum drug concentration (C _max) and area under the concentration–time curve (AUC)] in rats administered PF-06438179 or infliximab-EU were similar, with mean exposure ratio of PF-06438179 relative to infliximab-EU ranging from 0.88 to 1.16. No rats developed anti-drug antibodies. A 2-week IV toxicity study was conducted with once-weekly administration of 10 or 50 mg/kg of PF-06438179 to male and female rats. PF-06438179-related hyperplasia of sinusoidal cells occurred in the liver in rats administered 50 mg/kg, but was not adverse based on its minimal to mild severity. The no-observed adverse-effect level for PF-06438179 was 50 mg/kg. At this dose, C _max was 1360 µg/mL and AUC at 168 h was 115,000 µg h/mL on day 8.

Conclusions

The analytical and nonclinical studies have supported advancement of PF-06438179 into global comparative clinical trials.

Funding

Pfizer Inc.

     

Automatic adjustment of pressure support by a computer-driven knowledge-based system during noninvasive ventilation: a feasibility study

Objective

To evaluate the feasibility of using a knowledge-based system designed to automatically titrate pressure support (PS) to maintain the patient in a “respiratory comfort zone” during noninvasive ventilation (NIV) in patients with acute respiratory failure.

Design and setting

Prospective crossover interventional study in an intensive care unit of a university hospital.

Patients

Twenty patients.

Interventions

After initial NIV setting and startup in conventional PS by the chest physiotherapist NIV was continued for 45?min with the automated PS activated.

Measurements and results

During automated PS minute-volume was maintained constant while respiratory rate decreased significantly from its pre-NIV value (20?±?3 vs. 25?±?3?bpm). There was a trend towards a progressive lowering of dyspnea. In hypercapnic patients PaCO₂ decreased significantly from 61?±?9 to 51?±?2?mmHg, and pH increased significantly from 7.31?±?0.05 to 7.35?±?0.03. Automated PS was well tolerated. Two system malfunctions occurred prompting physiotherapist intervention.

Conclusions

The results of this feasibility study suggest that the system can be used during NIV in patients with acute respiratory failure. Further studies should now determine whether it can improve patient-ventilator interaction and reduce caregiver workload.

     

Preliminary Results that Assess Metformin Treatment in a Preclinical Model of Pancreatic Cancer Using Simultaneous [<Superscript>18</Superscript>F]FDG PET and acidoCEST MRI

Purpose

We sought to determine if the synergy between evaluations of glucose uptake in tumors and extracellular tumor acidosis measured with simultaneous positron emission tomography (PET)/magnetic resonance imaging (MRI) can improve longitudinal evaluations of the response to metformin treatment.

Procedures

A standard 2-deoxy-2-[¹⁸F]fluoro-D-glucose ([¹⁸F]FDG) PET protocol that evaluates glucose uptake in tumors, and a standard acidoCEST MRI protocol that measures extracellular pH (pHe) in tumors, were simultaneously performed to assess eight vehicle-treated (control) mice and eight metformin-treated mice 1 day before treatment, 1 day after initiating daily treatment with metformin, and 7 days after initiating treatment. Longitudinal changes in SUV_max and extracellular pH (pHe) were evaluated for each treatment group, and differences in SUV_max and pHe between metformin-treated and control groups were also evaluated.

Results

MRI acquisition protocols had little effect on the PET count rate, and the PET instrumentation had little effect on image contrast during acidoCEST MRI, verifying that [¹⁸F]FDG PET and acidoCEST MRI can be performed simultaneously. The average SUV_max of the tumor model had a significant decrease after 7 days of treatment with metformin, as expected. The average tumor pHe decreased after 7 days of metformin treatment, which reflected the inhibition of the consumption of cytosolic lactic acid caused by metformin. However, the average SUV_max of the tumor model was not significantly different between the metformin-treated and control groups after 7 days of treatment, and average pHe was also not significantly different between these groups. For comparison, the combination of average SUV_max and pHe measurements significantly differed between the treatment group and control group on Day 7.

Conclusions

[¹⁸F]FDG PET and acidoCEST MRI studies can be performed simultaneously. The synergistic combination of assessing glucose uptake and tumor acidosis can improve differentiation of a drug-treated group from a control group during drug treatment of a tumor model.

     

Effects of mannitol alone and mannitol plus furosemide on renal oxygen consumption,blood flow and glomerular filtration after cardiac surgery

Objective

Imbalance of the renal medullary oxygen supply/demand relationship can cause hypoxic medullary damage and ischaemic acute renal failure (ARF). The use of mannitol for prophylaxis/treatment of clinical ischaemic ARF is controversial and the effect of mannitol on renal oxygenation in man has not yet been investigated. We evaluated the effects of mannitol on renal oxygen consumption (RVO₂)_, renal blood flow (RBF) and glomerular filtration rate (GFR) in postoperative patients.

Design

Prospective interventional study.

Setting

University hospital cardiothoracic ICU.

Patients

Ten uncomplicated mechanically ventilated and sedated postcardiac surgery patients with preoperatively normal renal function.

Interventions

Mannitol infusion (225 mg/kg + 75 mg/kg/h) and combined mannitol and furosemide infusion (0.25 mg/kg + 0.25 mg/kg/h).

Measurements and results

Systemic haemodynamics were evaluated by a pulmonary artery catheter. RBF and GFR were measured by the renal vein thermodilution technique and by renal extraction of ⁵¹Cr–EDTA, respectively. Mannitol increased urine flow (60%), GFR (20%) and filtration fraction (FF) (20%) with no change in RBF. This was accompanied by an increase in renal sodium reabsorption (18%), RVO₂ (19%) and renal oxygen extraction (21%). When combined with mannitol, furosemide normalised sodium reabsorption, RVO₂, renal oxygen extraction with no change in RBF, while GFR and FF were still elevated compared to control.

Conclusions

In patients with normal renal function, mannitol increases GFR, which increases tubular sodium load, sodium reabsorption and RVO₂ after cardiac surgery. The lack of effect on RBF, indicates that mannitol impairs the renal oxygen supply/demand relationship. Furosemide normalised renal oxygenation when combined with mannitol.

     

Pharmacokinetics and Safety of Amenamevir in Healthy Subjects: Analysis of Four Randomized Phase 1 Studies

Introduction

Amenamevir (ASP2151) is a nonnucleoside antiherpesvirus compound available for the treatment of varicella–zoster virus infections. In this article we summarize the findings of four phase 1 studies in healthy participants.

Methods

Four randomized phase 1 studies investigated the safety and pharmacokinetics of single and multiple doses of amenamevir, including the assessment of age group effect (nonelderly vs elderly), food effect, and the relative bioavailability of two formulations. Amenamevir was administered orally at various doses as a single dose (5–2400 mg) or daily (300 or 600 mg/day) for 7 days.

Results

Following single and multiple oral doses, amenamevir demonstrated a less than dose proportional increase in the pharmacokinetic parameters area under the plasma drug concentration versus time curve from time zero to infinity (AUC_inf) and C _max. After single and multiple oral 300-mg doses of amenamevir, no apparent differences in pharmacokinetics were observed between nonelderly and elderly participants. In contrast, with the amenamevir 600-mg dose both the area under the plasma drug concentration versus time curve from time zero to 24 h and C _max were slightly increased and renal clearance was decreased in elderly participants. The pharmacokinetics of amenamevir was affected by food, with AUC_inf increased by about 90%. In the bioavailability study, AUC_inf and C _max were slightly lower following tablet versus capsule administration (decreased by 14 and 12%, respectively), with relative bioavailability of 86%. The different amenamevir doses and formulations were safe and well tolerated; no deaths or serious adverse events were reported.

Conclusion

Amenamevir had less than dose proportional pharmacokinetic characteristics. Age may have an influence on amenamevir pharmacokinetics; however, the effect was considered minimal. The pharmacokinetics of amenamevir were affected by food, with AUC_inf almost doubling when amenamevir was administered with food. The concentration versus time profile of the tablet was slightly lower than that of the capsule; the relative bioavailability of the tablet versus the capsule was 86%. Amenamevir was safe and well tolerated in the dose range investigated.

Funding

Astellas Pharma.

Trial registration

ClinicalTrials.gov identifiers NCT02852876 (15L-CL-002) and NCT02796118 (15L-CL-003).

     

A Phase 1 Pharmacokinetic Study of Cysteamine Bitartrate Delayed-Release Capsules Following Oral Administration with Orange Juice,Water, or Omeprazole in Cystinosis

Introduction

Cystinosis is a rare, metabolic, autosomal recessive, genetic lysosomal storage disorder characterized by an accumulation of cystine in various organs and tissues. Cysteamine bitartrate (CB) is a cystine-depleting aminothiol agent approved in the United States and Europe in immediate-release and delayed-release (DR) formulations for the treatment of nephropathic cystinosis in children and adults. It is recommended that CBDR be administered with fruit juice (except grapefruit juice) for maximum absorption. Omeprazole is a proton pump inhibitor that inhibits gastric acid secretion and, theoretically, may cause the premature release of cysteamine by increasing intragastric pH, thereby affecting the PK of CBDR.

Methods

This open-label, three-period, randomized study in healthy adult subjects was designed primarily to compare the pharmacokinetics of CBDR capsules after a single oral dose administered with orange juice, water, or multiple oral doses of omeprazole with water at steady state. A total of 32 subjects were randomly assigned to receive study agents in one of two treatment sequences.

Results

All subjects completed the study and baseline characteristics of the overall population and the two treatment sequence populations were similar. Peak mean plasma cysteamine concentrations following co-administration of CBDR capsules with orange juice (1892 ng/mL) were higher compared with co-administration with water (1663 ng/mL) or omeprazole 20 mg and water (1712 ng/mL). Mean time to peak plasma concentration was shorter with omeprazole co-administration (2.5 h) compared with orange juice (3.5 h) or water (3.0 h). Statistical comparisons between treatment groups indicated that exposure as assessed by AUC_0–t, AUC_0–∞, and C_max were all within the 80–125% bioequivalence ranges for all comparisons. All treatments were generally well tolerated.

Conclusion

Overall, the pharmacokinetics of cysteamine bitartrate DR capsules are not significantly impacted by co-administration with orange juice, water only, or omeprazole (with water).

Funding

Horizon Pharma, Inc.

     

Pharmacokinetics and safety of single and multiple doses of Asacol tablets in Japanese healthy volunteers

Introduction

The pharmacokinetics and safety of Asacol^® (Tillotts Pharma AG, Ziefen, Switzerland), which has been used worldwide to treat ulcerative colitis and Crohn’s disease, were studied in Japanese healthy male volunteers.

Methods

Drug plasma concentrations and urinary and fecal excretions after a single dose (400–4800 mg) and multiple doses (3600 mg/day for 7 days) were investigated.

Results

All adverse events were “not serious.” The peak plasma concentration (C_max) was reached at 12.3–18.0 hours after a single dose, and the C_max and area under the plasma concentration-time curve (AUC) of mesalazine and its N-acetyl metabolite were proportional to the doses. The C_max and AUC in non-Japanese subjects reported in the literature were closely correlated to findings in Japanese subjects, and external excretions were also similar in the Japanese and non-Japanese subjects.

Conclusions

Asacol was safe and well tolerated in this Japanese population, and the non-Japanese clinical data could be extrapolated to the Japanese population.