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Oral endocrine therapies (OET) for breast cancer treatment need to be taken over a long period of time and are associated with considerable side effects. Therefore, adherence to OET is an important issue and of high clinical significance for breast cancer patients' caregivers. We hypothesized that a new bioanalytical strategy based on liquid chromatography and high-resolution mass spectrometry might be suitable for unbiased adherence monitoring (AM) of OET. Four different biomatrices (plasma, urine, finger prick blood by volumetric absorptive microsampling (VAMS), oral fluid (OF)) were evaluated regarding their suitability for AM of the OET abemaciclib, anastrozole, exemestane, letrozole, palbociclib, ribociclib, tamoxifen, and endoxifen. An analytical method was developed and validated according to international recommendations. The analytical procedures were successfully validated in all sample matrices for most analytes, even meeting requirements for therapeutic drug monitoring. Chromatographic separation of analytes was achieved in less than 10 min and limits of quantification ranged from 1 to 1000 ng/mL. The analysis of 25 matching patient samples showed that AM of OET is possible using all four matrices with the exception of, e.g., letrozole and exemestane in OF. We were able to show that unbiased bioanalytical AM of OET was possible using different biomatrices with distinct restrictions. Sample collection of VAMS was difficult in most cases due to circulatory restraints and peripheral neuropathy in fingers and OF sampling was hampered by dry mouth syndrome in some cases. Although parent compounds could be detected in most of the urine samples, metabolites should be included when analyzing urine or OF. Plasma is currently the most suitable matrix due to available reference concentrations., (© 2024. The Author(s).)

Background: Population pharmacokinetic methods were used to characterize the pharmacokinetics of fluticasone furoate (FF), umeclidinium (UMEC), and vilanterol (VI) in patients with chronic obstructive pulmonary disease (COPD) when administered as a fixed-dose combination via a single closed inhaler., Methods: Plasma concentration data from three studies were analyzed using non-linear mixed-effects modeling in NONMEM ® ., Results: The pooled dataset consisted of 2948, 2589, and 3331 FF, UMEC, and VI observations from 714, 622, and 817 patients with COPD, respectively. There were 41%, 13%, and 21% of observations below the quantification limit for FF, UMEC, and VI, respectively. The pharmacokinetics of FF, UMEC, and VI were all adequately described by a two-compartment model with first-order absorption. The following covariates were statistically significant, but none were considered to be clinically relevant. For FF, Japanese heritage and FF/VI treatment on apparent inhaled clearance (CL/F) with FF CL/F 35% lower in patients of Japanese heritage across all treatments and FF CL/F 42% higher in patients with COPD following FF/VI administration. This is in line with the product label. For UMEC, weight, age, and smoking status on CL/F and weight on apparent volume of distribution (V2/F) with every 10% increase in age from 60 years of age leading to approximately a 6% decrease in UMEC CL/F and every 10% increase in weight from 70 kg leading to approximately a 6% increase in UMEC CL/F and approximately an 8% increase in UMEC V2/F. For a subject with COPD who smoked, UMEC CL/F was 28% higher. For VI, weight on CL/F and smoking status on V2/F with an approximately 4% increase in VI CL/F for every 10% increase in weight from 70 kg, and for a subject with COPD who smoked, VI V2/F was 46% higher. The majority of these covariates have been previously identified in historical analyses. None of these effects were clinically relevant in terms of systemic exposures and do not warrant dose adjustment., Conclusions: All FF, UMEC, and VI plasma concentrations were well interspersed with historical data and were all adequately described by a two-compartment model with first-order absorption. There were no clinically relevant differences in FF, UMEC, or VI systemic exposures when administered as FF/UMEC/VI, FF/VI + UMEC, or the dual combinations FF/VI and/or UMEC/VI.

Fluticasone furoate (FF) and vilanterol trifenatate (VT) is a widely prescribed combination in the management of asthma and chronic obstructive pulmonary disease. In the present study, two quantitative methods based on HPLC-UV and spectrofluorimetric analysis had been developed and validated for simultaneous estimation of FF and VT in rabbit plasma using baclomethasone as internal standard (ISTD). Analytes and ISTD were separated from plasma using simple step of protein precipitation with acetonitrile. Chromatographic separation was achieved on Spherisorb S5 ODS2 (250 mm × 4.6 mm, 5.0 µm) column using mobile phase that constitute acetonitrile-0.01% glacial acetic acid in water (70:30, v/v) and then detected on a UV detector at 235 nm wavelength. Spectrofluorimetric detection was performed using absorption/emission wavelength (λ abs/em ) of 286/352 nm and 362/407 nm for FF and VT, respectively. For both analytes, linearity ranged from 4-200 ng/mL to 10-200 ng/mL using HPLC-UV and spectrofluorimetric method, respectively. Methods were validated as per FDA recommendations. Statistical analysis revealed that these detection methods are statistically insignificant difference and can be used interchangeably without any bias. Further, these methods were applied in pharmacokinetic study for simultaneous estimation of FF and VT in rabbit plasma., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: Previous studies have highlighted a relationship between reduction in rate of exacerbations with therapies containing inhaled corticosteroids (ICS) and baseline blood eosinophil count in patients with chronic obstructive pulmonary disease (COPD). The IMPACT trial showed that once-daily single-inhaler triple therapy significantly reduced exacerbations versus dual therapies. Blood eosinophil counts and smoking status could be important modifiers of treatment response to ICS. We aimed to model these relationships and their interactions, including outcomes other than exacerbations., Methods: IMPACT was a phase 3, randomised, double-blind, parallel-group, 52-week global study comparing once-daily single-inhaler triple therapy (fluticasone furoate-umeclidinium-vilanterol) with dual inhaled therapy (fluticasone furoate-vilanterol or umeclidinium-vilanterol). Eligible patients had moderate-to-very-severe COPD and at least one moderate or severe exacerbation in the previous year. We used fractional polynomials to model continuous blood eosinophil counts. We used negative binomial regression for numbers of moderate and severe exacerbations, severe exacerbations, and pneumonia. We modelled differences at week 52 in trough FEV 1 , St George's Respiratory Questionnaire (SGRQ) total score, and Transition Dyspnoea Index using repeated measurements mixed effect models. IMPACT was registered with ClinicalTrials.gov, number NCT02164513., Findings: The magnitude of benefit of regimens containing ICS (fluticasone furoate-umeclidinium-vilanterol n=4151 and fluticasone furoate-vilanterol n=4134) in reducing rates of moderate and severe exacerbations increased in proportion with blood eosinophil count, compared with a non-ICS dual long-acting bronchodilator (umeclidinium-vilanterol n=2070). The moderate and severe exacerbation rate ratio for triple therapy versus umeclidinium-vilanterol was 0·88 (95% CI 0·74 to 1·04) at blood eosinophil count less than 90 cells per μL and 0·56 (0·47 to 0·66) at counts of 310 cells per μL or more; the corresponding rate ratio for fluticasone furoate-vilanterol versus umeclidinium-vilanterol was 1·09 (0·91 to 1·29) and 0·56 (0·47 to 0·66), respectively. Similar results were observed for FEV 1 , Transition Dyspnoea Index, and SGRQ total score; however, the relationship with FEV 1 was less marked. At blood eosinophil counts less than 90 cells per μL and at counts of 310 cells per μL or more, the triple therapy versus umeclidinium-vilanterol treatment difference was 40 mL (95% CI 10 to 70) and 60 mL (20 to 100) for trough FEV 1 , -0·01 (-0·68 to 0·66) and 0·30 (-0·37 to 0·97) for Transition Dyspnoea Index score, and -0·01 (-1·81 to 1·78) and -2·78 (-4·64 to -0·92) for SGRQ total score, respectively. Smoking status modified the relationship between observed efficacy and blood eosinophil count for moderate or severe exacerbations, Transition Dyspnoea Index, and FEV 1 , with former smokers being more corticosteroid responsive at any eosinophil count than current smokers., Interpretation: This analysis of the IMPACT trial shows that assessment of blood eosinophil count and smoking status has the potential to optimise ICS use in clinical practice in patients with COPD and a history of exacerbations., Funding: GlaxoSmithKline., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Exemestane (EXE) is an aromatase inhibitor used for the prevention and treatment of estrogen receptor-positive breast cancer. Although the known major metabolic pathway for EXE is reduction to form the active 17 β -dihydro-EXE (17 β -DHE) and subsequent glucuronidation to 17 β -hydroxy-EXE-17-O- β -D-glucuronide (17 β -DHE-Gluc), previous studies have suggested that other major metabolites exist for exemestane. In the present study, a liquid chromatography-mass spectrometry (LC-MS) approach was used to acquire accurate mass data in MS E mode, in which precursor ion and fragment ion data were obtained simultaneously to screen novel phase II EXE metabolites in urine specimens from women taking EXE. Two major metabolites predicted to be cysteine conjugates of EXE and 17 β -DHE by elemental composition were identified. The structures of the two metabolites were confirmed to be 6-methylcysteinylandrosta-1,4-diene-3,17-dione (6-EXE-cys) and 6-methylcysteinylandrosta-1,4-diene-17 β -hydroxy-3-one (6-17 β -DHE-cys) after comparison with their chemically synthesized counterparts. Both underwent biosynthesis in vitro in three stepwise enzymatic reactions, with the first involving glutathione conjugation. The cysteine conjugates of EXE and 17 β -DHE were subsequently quantified by liquid chromatography-mass spectrometry in the urine and matched plasma samples of 132 subjects taking EXE. The combined 6-EXE-cys plus 6-17 β -DHE-cys made up 77% of total EXE metabolites in urine (vs. 1.7%, 0.14%, and 21% for EXE, 17 β -DHE, and 17 β -DHE-Gluc, respectively) and 35% in plasma (vs. 17%, 12%, and 36% for EXE, 17 β -DHE, and 17 β -DHE-Gluc, respectively). Therefore, cysteine conjugates of EXE and 17 β -DHE appear to be major metabolites of EXE in both urine and plasma., (Copyright © 2018 The Author(s).)

Exemestane (EXE) is an aromatase inhibitor used for the prevention and treatment of breast cancer. The major metabolic pathway for EXE is reduction to form the active 17β-dihydro-EXE (17β-DHE) and subsequent glucuronidation to 17β-hydroxy-EXE-17-O-β-D-glucuronide (17β-DHE-Gluc) by UGT2B17. The aim of the present study was to determine the effects of UGT2B17 copy number variation on the levels of urinary and plasma 17β-DHE-Gluc and 17β-DHE in patients taking EXE. Ninety-six post-menopausal Caucasian breast cancer patients with ER+ breast tumors taking 25 mg EXE daily were recruited into this study. UGT2B17 copy number was determined by a real-time PCR copy number variant assay and the levels of EXE, 17β-DHE and 17β-DHE-Gluc were quantified by UPLC/MS in patients' urine and plasma. A 39-fold decrease (P<0.0001) in the levels of creatinine-adjusted urinary 17β-DHE-Gluc was observed among UGT2B17 (*2/*2) subjects vs subjects with the UGT2B17 (*1/*1) genotype. The plasma levels of 17β-DHE-Gluc was decreased 29-fold (P<0.0001) in subjects with the UGT2B17 (*2/*2) genotype vs subjects with UGT2B17 (*1/*1) genotype. The levels of plasma EXE-adjusted 17β-DHE was 28% higher (P=0.04) in subjects with the UGT2B17 (*2/*2) genotype vs subjects with the UGT2B17 (*1/*1) genotype. These data indicate that UGT2B17 is the major enzyme responsible for 17β-DHE-Gluc formation in vivo and that the UGT2B17 copy number variant may play a role in inter-individual variability in 17β-DHE levels in vivo.

Discovery of clinical and genetic predictors of exemestane pharmacokinetics was attempted in 246 postmenopausal patients with breast cancer enrolled on a prospective clinical study. A sample was collected 2 h after exemestane dosing at a 1- or 3-month study visit to measure drug concentration. The primary hypothesis was that patients carrying the low-activity CYP3A4*22 (rs35599367) single-nucleotide polymorphism (SNP) would have greater exemestane concentration. Additional SNPs in genes relevant to exemestane metabolism (CYP1A1/2, CYP1B1, CYP3A4, CYP4A11, AKR1C3/4, AKR7A2) were screened in secondary analyses and adjusted for clinical covariates. CYP3A4*22 was associated with a 54% greater exemestane concentration (P<0.01). Concentration was greater in patients who reported White race, had elevated aminotransferases, renal insufficiency, lower body mass index and had not received chemotherapy (all P<0.05), and CYP3A4*22 maintained significance after adjustment for covariates (P<0.01). These genetic and clinical predictors of exemestane concentration may be useful for treatment individualization in patients with breast cancer.

This study was envisaged to demonstrate the potential of exemestane loaded phospholipid/sodium deoxycholate solid dispersions (EXE-PL/SDC-SDs) on the solubility and oral bioavailability of EXE. Initial studies were performed to screen the best suitable phospholipid among lysophosphatidylcholine, Phospholipon® P80H and Lipoid® E80S for solid dispersion preparation. Further studies were carried out to optimize the molar concentration of phospholipid and sodium deoxycholate (SDC) for EXE-PL/SDC-SDs preparation. Optimized EXE-PL/SDC-SDs was prepared using Lipoid® E80S and SDC in 1:4M concentration, respectively and lyophilized using 10% w/w 2-hydroxypropyl-β-cyclodextrin (2-HPCD). The physical state of EXE in lyophilized formulation was confirmed by DSC and PXRD. Lyophilized formulation exhibits a significant increase in solubility and dissolution rate as compared to free drug EXE. Apparent permeability study was performed on Caco-2 cell line for 2h. The lyophilized EXE-PL/SDC-SDs exhibits 4.6-fold increase in absorptive transport as compared to EXE. Pharmacokinetic study in fasted female Sprague-Dawley rats revealed a 2.3-fold increase in AUC 0-72h . Thus, the results suggest that PL/SDC-SDs is a promising carrier for EXE delivery., (Copyright © 2017 Elsevier B.V. All rights reserved.)

In this study, we present a case of falsely elevated oestradiol (E 2 ) concentration, determined by two immunoassays, in a breast cancer patient receiving exemestane therapy. The positive bias of immunochemical measurements was revealed using liquid chromatography tandem mass spectrometry which showed undetectable E 2 concentration. The discrepancy is expected to be a consequence of the structural resemblance of E 2 and exemestane sharing the same steroidal backbone. Inaccurate laboratory findings in therapy monitoring, as in this case, may lead to unnecessary changes of therapy.

A highly sensitive and rapid ultra performance liquid chromatography-tandem mass spectrometry method has been developed for the simultaneous determination of fluticasone propionate (FP) and its major metabolite, fluticasone propionate-17beta-carboxylic acid (FP 17β-CA) in human plasma. The analytes and their deuterated internal standards, FP-d3 and FP 17β-CA-d3 were extracted from 500μL plasma samples by solid phase extraction on Oasis MAX cartridges. The chromatographic analysis was performed on ACQUITY UPLC BEH C18 (50mm×2.1mm, 1.7μm) column using methanol-acetonitrile (50:50, v/v) and 2.0mM ammonium trifluroacetate (ATFA) (85:15, v/v) as the mobile phase. Following separation of the analytes, protonated precursor→product ion transitions (FP: m/z 501.1→293.2, FP17β-CA: m/z 453.3→293.2, FP-d3: m/z 504.2→293.2, FP 17β-CA-d3: m/z 456.3→293.2) were monitored on FP 17β-CA a triple quadrupole mass spectrometer, operating in multiple reaction monitoring (MRM) and positive ionization mode. The calibration curves were established in the range of 0.5-100pg/mL with a correlation coefficient (r 2 )≥0.9992 for both the analytes. The intra-batch and inter-batch accuracy and precision varied from 95.5-103.4% and 0.74-5.06% across quality controls for both the analytes. The mean assay recoveries for FP and FP 17β-CA were 84.2% and 93.5% respectively. The validated method was successfully applied to support a bioequivalence study of 200μg FP, administered using nasal spray formulation in 18 healthy Indian subjects. Reproducibility of the method was assessed by reanalysis of 98 incurred study samples., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background and Objectives: Previous pharmacokinetic studies of the inhaled corticosteroid, fluticasone furoate (FF), and the long-acting, beta2-receptor agonist, vilanterol (VI) have been performed in relatively small populations using non-compartmental pharmacokinetic methods and censored data (due to low drug exposure relative to assay sensitivity). This paper presents a population pharmacokinetic analysis, utilizing pooled concentration-time data from clinical studies in healthy subjects and from global trials in patients with chronic obstructive pulmonary disease (COPD). The objective of this analysis was to characterize the population pharmacokinetics of FF and VI following once-daily inhalation dosing of FF/VI or the individual components (FF and VI) and to identify significant covariates that impact systemic exposure to FF and VI in this population., Methods: Population pharmacokinetic methods that maximize the likelihood of all data were developed to describe systemic exposure to FF and VI following once-daily FF/VI, FF, or VI, and to identify significant covariates that impact the pharmacokinetics. COPD patients (N = 1225 for the FF analysis and N = 1091 for the VI analysis; 94 and 93 % of total data, respectively) and healthy subjects contributed to the analysis., Results: FF data were described by a two-compartment model with first-order absorption and elimination. The population grouping "race" was a significant covariate on inhaled clearance (CL/F). The area under the curve over 24 h (AUC 0-24 ) for FF was higher for East Asian, Japanese, and South East Asian (average 23-30 %) and Asian Central, White Arabic, American Indian/Native Alaskan, and 'other' (10-26 %) subjects compared with White/Caucasians. VI pharmacokinetics were described by a three-compartment model with zero-order absorption and first-order elimination. Significant demographic covariates identified to affect pharmacokinetics of VI were age [on CL/F and central volume (V 1 /F)], bodyweight (on CL/F), sex and smoking (on V 1 /F)., Conclusions: While significant effects of the covariates were observed in this study, the magnitude of these effects on systemic exposure is not large enough to warrant FF/VI dosage adjustment in patients with COPD., Competing Interests: Compliance with Ethical Standards Funding All of the studies used in this analysis were funded by GSK. Conflict of interest Sarah Siederer and Shuying Yang are employed by and hold shares in GSK. Ann Allen was an employee of GSK at the time of these analyses. Ethical approval All procedures were carried out in accordance with the International Conference on Harmonisation E6 guidelines for Good Clinical Practice and the principles of the Declaration of Helsinki. The studies described in this paper were approved by independent institutional review boards and ethics committees at all study sites. A full list of approving bodies is included in Appendix 1. Informed consent Written informed consent was obtained from each subject prior to the performance of any study-specific procedures.

Background: The short-term benefits of inhaled corticosteroids for patients with chronic obstructive pulmonary disease (COPD) are greater in patients with evidence of eosinophilic airway inflammation. We investigated whether blood eosinophil count is a useful biomarker of the long-term effect of the inhaled corticosteroid fluticasone furoate on exacerbation frequency., Methods: We did a post-hoc analysis of data from two replicate, randomised, double-blind trials of 12 months' duration (Sept 25, 2009 to Oct 21, 2011 and Oct 17, 2011) in which once a day vilanterol 25 μg was compared with 25 μg vilanterol plus 50 μg, 100 μg, or 200 μg fluticasone furoate in patients with moderate-to-severe COPD and a history of one or more exacerbation in the previous year. We compared exacerbation rates according to two baseline eosinophil cell count strata (<2% and ≥2%), and according to four baseline percentage groupings. We also assessed lung function and incidence of pneumonia per strata in treatment groups., Findings: We included 3177 patients in the analyses, with 2083 patients (66%) having an eosinophil count of 2% or higher at study entry. Across all doses of inhaled corticosteroids, fluticasone furoate and vilanterol reduced exacerbations by 29% compared with vilanterol alone (mean 0·91 vs 1·28 exacerbations per patient per year; p<0·0001) in patients with eosinophil counts of 2% or higher, and by 10% (0·79 vs 0·89; p=0·2827) in patients with eosinophil counts lower than 2%. Reductions in exacerbations with fluticasone furoate and vilanterol, compared with vilanterol alone, were 24% in patients with baseline eosinophil counts of ≥2-<4%, 32% for those with counts of 4-<6%, and 42% for those with eosinophil counts of ≥6%. In patients treated with vilanterol alone, exacerbation rates increased progressively with increasing eosinophil count percentage category. Improvement in trough forced expiratory volume in 1 s (FEV1) and the increased risk of pneumonia with fluticasone furoate and vilanterol compared with vilanterol alone were not associated with eosinophil count., Interpretation: Blood eosinophil count is a promising biomarker of response to inhaled corticosteroids in patients with COPD. Blood eosinophil count could potentially be used to stratify patients for different exacerbation rate reduction strategies., Funding: GlaxoSmithKline (study ID 201595)., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

A novel, rapid and sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed and validated for the evaluation of exemestane pharmacokinetics and its metabolites, 17β-dihydroexemestane (active metabolite) and 17β-dihydroexemestane-17-O-β-D-glucuronide (inactive metabolite) in human plasma. Their respective D3 isotopes were used as internal standards. Chromatographic separation of analytes was achieved using Thermo Fisher BDS Hypersil C18 analytic HPLC column (100 × 2.1 mm, 5 μm). The mobile phase was delivered at a rate of 0.5 mL/min by gradient elution with 0.1% aqueous formic acid and acetonitrile. The column effluents were detected by API 4000 triple quadrupole mass spectrometer using electrospray ionisation (ESI) and monitored by multiple reaction monitoring (MRM) in positive mode. Mass transitions 297 > 121 m/z, 300 > 121 m/z, 299 > 135 m/z, 302 > 135 m/z, 475 > 281 m/z, and 478 > 284 m/z were monitored for exemestane, exemestane-d3, 17β-dihydroexemestane, 17β-dihydroexemestane-d3, 17β-dihydroexemestane-17-O-β-D-glucuronide, and 17β-dihydroexemestane-17-O-β-D-glucuronide-d3 respectively. The assay demonstrated linear ranges of 0.4-40.0 ng/mL, for exemestane; and 0.2-15.0 ng/mL, for 17β-dihydroexemestane and 17β-dihydroexemestane-17-O-β-D-glucuronide, with coefficient of determination (r2) of > 0.998. The precision (coefficient of variation) were ≤10.7%, 7.7% and 9.5% and the accuracies ranged from 88.8 to 103.1% for exemestane, 98.5 to 106.1% for 17β-dihydroexemestane and 92.0 to 103.2% for 17β-dihydroexemestane-17-O-β-D-glucuronide. The method was successfully applied to a pharmacokinetics/dynamics study in breast cancer patients receiving exemestane 25 mg daily orally. For a representative patient, 20.7% of exemestane in plasma was converted into 17β-dihydroexemestane and 29.0% of 17β-dihydroexemestane was inactivated as 17β-dihydroexemestane-17-O-β-D-glucuronide 24 hours after ingestion of exemestane, suggesting that altered 17-dihydroexemestane glucuronidation may play an important role in determining effect of exemestane against breast cancer cells.

Purpose: To investigate the potential for systemic pharmacokinetic (PK) and pharmacodynamic (PD) interactions between inhaled fluticasone furoate (FF) and vilanterol (VI) when delivered simultaneously via the ELLIPTA™ dry powder inhaler (DPI)., Methods: Randomized, double-blind, placebo-controlled, crossover study. Healthy subjects (n = 16) received single doses of FF (800 mcg), VI (100 mcg), FF/VI (800/100 mcg), and placebo. Endpoints measured were systemic PD (FF: serum cortisol; VI: heart rate), FF and VI plasma PK (0-48 hours), pharyngometry, inhalation and breath hold profiles and safety assessments., Results: Treatment differences [90% confidence interval (CI)] in weighted mean serum cortisol (0-24 hours) were 12.3% [4.4, 20.9] (FF/VI vs. FF) and for maximum heart rate (0-4 hours) were -1.2 bpm [-4.6, 2.1] (FF/VI vs. VI). When delivered simultaneously, FF and VI systemic exposures were slightly lower (<20%) versus delivery of either agent alone (although this was not a formal bioequivalence study). In vitro simulation of selected inhalation profiles and modeling supported the PK and PD findings. FF/VI, FF and VI were well tolerated with an AE incidence comparable to placebo., Conclusions: These results suggest there was a slight PK interaction and no PD interactions of concern between inhaled FF and VI when delivered simultaneously via the ELLIPTA DPI in healthy subjects., (© 2014, The American College of Clinical Pharmacology.)

Purpose: Some patients are unable to generate the peak inspiratory flow rate (PIFR) necessary to de-agglomerate drug particles from dry powder inhalers (DPIs). In this study we tested the hypothesis that the acoustic parameters of an inhalation are related to the PIFR and hence reflect drug delivery., Methods: A sensitivity analysis of the relationship of the acoustics of inhalation to simultaneously recorded airflow, in a cohort of volunteers (n = 92) was performed. The Next Generation Impactor (NGI) was used to assess in vitro drug delivery from salmeterol/fluticasone and salbutamol Diskus™ DPIs. Fine particle fraction, FPF, (<5 μm) was measured at 30-90 l/min for 2-6 s and correlated with acoustically determined flow rate (IFRc). In pharmacokinetic studies using a salbutamol (200 μg) Diskus™, volunteers inhaled either at maximal or minimal effort on separate days., Results: PIFRc was correlated with spirometrically determined values (R (2) = 0.88). In in vitro studies, FPF increased as both flow rate and inhalation duration increased for the salmeterol/fluticasone Diskus™ (Adjusted R (2) = 0.95) and was proportional to flow rate only for the salbutamol Diskus™ (Adjusted R (2) = 0.71). In pharmacokinetic studies, blood salbutamol levels measured at 20 min were significantly lower when PIFRc was less than 60 l/min, p < 0.0001., Conclusion: Acoustically-determined PIFR is a suitable method for estimating drug delivery and for monitoring inhalation technique over time.

Background: The object of this study was to assess whether a capsule-based and multidose dry powder inhaler containing salmeterol (as xinafoate salt) 50 μg plus fluticasone propionate (FP) 250 μg [combination (SFC 50/250)] could be equivalent in terms of in vivo drug delivery and systemic exposure., Methods: This was a randomized, double-blind, double-dummy, replicate treatment design comparative bioavailability study of SFC 50/250 delivered in a capsule-based inhaler (Rotahaler®) and a multidose dry powder inhaler (Diskus®). Subjects with asthma or chronic obstructive pulmonary (COPD) disease (n=60) were randomized to receive twice-daily SFC 50/250 via a Rotahaler and via Diskus each for two 10-day treatment periods (GlaxoSmithKline Protocol ASR114334)., Results: For FP and salmeterol, the in vitro aerodynamic particle size profiles were within±15% of Diskus for the fine particle mass (FPM) and emitted dose (ED) using the Andersen Cascade Impactor, and ED, mass median aerodynamic diameter, and geometric standard deviation using the New Generation Impactor (NGI). This was also the case for FP but not salmeterol for FPM and fine particle dose using the NGI. For the combined asthma and COPD subjects, the plasma AUC and Cmax for FP and salmeterol were higher for Rotahaler:Rotahaler/Diskus geometric mean ratios (90% confidence intervals) for FP AUC0-τ of 1.52 (1.37-1.67) and Cmax of 1.94 (1.75-2.10) and salmeterol AUC0-τ of 1.15 (1.09-1.21) and Cmax of 1.56 (1.42-1.67). Corresponding values for the primary pharmacodynamic endpoint, weighted mean (0-12 hr) serum cortisol, were 0.928 (0.886-0.971). Inhaled FP/salmeterol via both inhalers was well-tolerated. One serious adverse event, considered possibly related to study medication, resulted in subject withdrawal from the study., Conclusions: The in vitro tests and systemic pharmacodynamic endpoints revealed no major differences between the two inhalers, but lacked predictive power and sensitivity to guide in vivo drug delivery performance and systemic exposure. Based on pharmacokinetic endpoints, the inhalers were not considered bioequivalent in terms of systemic exposure. Further studies to refine the Rotahaler performance are ongoing.

Three open-label, single-dose studies investigated the impact of hepatic or renal impairment on abiraterone acetate pharmacokinetics and safety/tolerability in non-cancer patients. Patients (n = 8 each group) with mild/moderate hepatic impairment or end-stage renal disease (ESRD), and age-, BMI-matched healthy controls received a single oral 1,000 mg abiraterone acetate (tablet dose); while patients (n = 8 each) with severe hepatic impairment and matched healthy controls received 125- and 2,000-mg abiraterone acetate (suspension doses), respectively (systemic exposure of abiraterone acetate suspension is approximately half to that of tablet formulation). Blood was sampled at specified timepoints up to 72 or 96 hours postdose to measure plasma abiraterone concentrations. Abiraterone exposure was comparable between healthy controls and patients with mild hepatic impairment or ESRD, but increased by 4-fold in patients with moderate hepatic impairment. Despite a 16-fold reduction in dose, abiraterone exposure in patients with severe hepatic impairment was about 22% and 44% of the Cmax and AUC∞ of healthy controls, respectively. These results suggest that abiraterone pharmacokinetics were not changed markedly in patients with ESRD or mild hepatic impairment. However, the capacity to eliminate abiraterone was substantially compromised in patients with moderate or severe hepatic impairment. A single-dose administration of abiraterone acetate was well-tolerated., (© 2014, The American College of Clinical Pharmacology.)

A novel spectrofluorimetric method to determine abiraterone acetate and its active metabolite, abiraterone was developed, based on the fact that fluorescence intensity of abiraterone acetate and abiraterone could be enhanced in β-cyclodextrin (β-CD) due to the formation of the inclusion complex. The inclusion interaction of β-CD and abiraterone acetate and the β-cyclodextrin sensitized spectrofluorimetry was examined. The various factors influencing fluorescence were discussed in details. The results showed that under the optimized conditions, the linear range of calibration curve for the determination of biraterone acetate and abiraterone was 0.20 ~ 6.0 μg/mL, and the detection limit (LOD) was 6.8 (r = 0.997) or 6.6 ng/mL (r = 0.996), respectively. No interference was observed from common co-existing substances or pharmaceutical excipient. The method was successfully applied to the analysis of abiraterone acetate in pharmaceutical formulation and abiraterone in human serum/urine.

Background: The isolated perfused rat lung (IPL) is a suitable model for studying lung-specific pharmacokinetics (PK) of inhaled drugs. So far, little has been known, however, whether the PK measured in the ex vivo organ corresponds to the PK measured in similarly exposed animals in vivo, in particular the endotracheally intubated rat (EIR). The purpose of the current research was to compare the PK of inhaled corticosteroid fluticasone furoate (FF) in the IPL and the EIR., Method: Aerosols of FF with mass median aerodynamic diameters ranging from 2.2 to 3.2 μm were generated with the DustGun aerosol generator. The IPL, perfused in the single-pass mode, was exposed via inhalation to 5.6 and 46 μg of FF. Following inhalation, the perfusate was repeatedly sampled for 100 min, after which the lungs were recovered for quantitation of remaining FF. Two groups of EIR were also exposed via inhalation to 7 μg of FF. One group was immediately euthanized for determination of the initial deposition of FF in the lungs. From the second group, four venous blood samples were drawn up to 4 hr after exposure. The animals were then sacrificed for determination of FF remaining in the lungs., Results: Following inhalation, FF was slowly disappearing from both the IPL and the lungs of the EIR, with a half-life of pulmonary retention of 4.3-4.9 hr for all three exposure series. For the low exposure levels, the concentration curve of FF in the IPL perfusate was similar in shape to that in venous blood of the EIR, with a Cmax of 1.0 and 0.8 nM for the IPL and the EIR, respectively., Conclusions: The results indicate that the IPL and the EIR, when used jointly in PK studies, can provide a detailed characterization of inhaled drugs or toxicants.

In vitro measures of aerosol particles size, such as the fine particle mass, play a pivotal role for approval of inhaled anti-asthmatic drugs. However, the validity as a measure of dose to the lungs in children lacks evidence. In this study we investigated for the first time the association between an in vivo estimate of lung dose of inhaled drug in children and the corresponding particle size segments assessed ex vivo. Lung dose of fluticasone propionate after inhalation from a dry powder inhaler (Diskus®) was studied in 23 children aged 4-7 and 12-15 years with mild asthma. Six-hour pharmacokinetics was assessed after single inhalation. The corresponding emitted mass of drug in segments of aerosol particle size was assessed ex vivo by replicating the inhalation flows recorded by transducers built into the Diskus® inhaler and re-playing them in a breathing simulator. There was no correlation between any inhaled particle size segment and lung dose assessed by pharmacokinetics and adjusted for age and body size. Measures of particles size segments were not related to lung dose in children. Until further evidence is provided it may be warranted to emphasize pharmacokinetic or pharmacodynamic assessments of drug delivery to the lung., (© The Author(s) 2013.)

Fluticasone propionate (FP) is an anti-inflammatory agent with topical and inhaled applications commonly used in the treatment of asthma in steroid-dependent individuals. The drug is used in racehorses to treat Inflammatory Airway Disease; this work was performed in order to advise on its use and detect potential misuse close to racing. Methods were developed for the extraction and analysis of FP from horse plasma and a carboxylic acid metabolite (FP-17βCOOH) from horse urine. The methods utilize ultra high performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) in order to detect the extremely low concentrations of analyte present in both matrices. The developed methods were used to analyse plasma and urine samples collected following inhaled administration of FP to six thoroughbred horses. FP was detected in plasma for a minimum of 72 h post-administration and FP-17βCOOH was detected in urine for approximately 18 h post-administration. The results show that it is possible to detect FP in the horse following inhaled administration., (Copyright © 2012 John Wiley & Sons, Ltd.)

The occurrence of several polyunsaturated testosterone related compounds (including 4,6-androstadien-3,17-dione and 4,6-androstadien-17β-ol-3-one) in urine after alkaline treatment of the sample has been recently reported. Although several experiments seem to indicate that they are testosterone metabolites, their origin is still unknown. In this study, it is demonstrated that these metabolites are produced from the degradation of cysteine conjugates. Several testosterone metabolites conjugated with cysteine have been synthesized and characterized by NMR techniques. Their detection in human urine has been performed by LC-MS/MS. The acquisition of several transitions in the SRM mode and the comparison between ion ratios and retention times allowed for the unequivocal confirmation of the presence of cysteine conjugates in urine. The analysis of urine samples collected after testosterone administration confirmed that synthesized cysteine conjugates are testosterone metabolites. The fact that these conjugates result in polyunsaturated compounds in urine after alkaline treatment was demonstrated by fraction collection and alkaline treatment of each fraction. Besides, the presence of these metabolites was also confirmed in human plasma. The formation of these metabolites implies an unreported metabolic biotransformation: 6,7-dehydrogenation as phase I metabolism followed by conjugation with glutathione and subsequent transformation to cysteine conjugates. Finally, the existence of similar metabolites for cortisol and progesterone was also confirmed by LC-MS/MS indicating that the presented metabolic pathway is not exclusively active in androgens, but common to progestagens and glucocorticoids., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background: To develop and validate an ultrasensitive bioanalytical assay for quantitation of fluticasone propionate in human plasma, aliquots of 0.6 ml of K(3)EDTA human plasma were treated with zinc sulfate solution and loaded onto a preconditioned SPE plate. The sample solutions were washed, eluted, dried and reconstituted. The extracted sample was injected onto a LC-MS/MS system and separated by a reverse-phase HPLC column with a 5 min gradient program, and detected by MS/MS for fluticasone propionate quantitation., Results: Linearity was from 1 to 200 pg/ml. The intra- and inter-day accuracy and precision of the assay met validation acceptance criteria. Various stabilities were established and interference drug assessment was evaluated. The assay has been used for clinical studies., Conclusion: This ultrasensitive method has been successfully validated using LC-MS/MS for determination of fluticasone propionate in human plasma at low pg/ml level.

A new method for the fast simultaneous quantification of fluticasone propionate and salmeterol from plasma samples by liquid chromatography-tandem mass spectrometry, with adequate sensitivity for pharmacokinetic applications, was developed and validated. The chromatographic separation and mass-spectrometric parameters were optimized for the retention and detection of the two compounds, despite quite different structures and properties. Two columns connected in series were used, cation-exchange (Zorbax 300-SCX, 5 cm x 2.1 mm, 5 μm) and octadecyl (Discovery HSC₁₈, 10 cm x 2.1 mm, 5 μm). The mass-spectrometric interface was operated in negative electrospray ionization mode; high sensitivity and lesser matrix effects were obtained, permitting smaller consumption of plasma. The sample preparation was based on supported liquid-liquid extraction in 96-well format plates that provided clean samples with a simplified procedure that was suitable for automation. The method was validated according to regulatory guidelines, by assessing lower limits of quantification, selectivity, linearity, accuracy, precision, extraction recoveries and matrix effects. A comparison with two other methods for the separate determination of fluticasone propionate and salmeterol in plasma samples, previously developed by our group, is presented. The statistical evaluation of the results obtained with the three methods on a set of unknown samples from treated patients demonstrated good correlation (R² 0.987 for fluticasone propionate and 0.967 for salmeterol).

Background: This randomized, double-blind, multicenter study was designed to evaluate the efficacy of inhaled once-daily fluticasone furoate (FF) administered in the evening in patients with persistent asthma not controlled by short-acting beta(2) agonists, and to determine the dose(s) suitable for further development., Methods: Of 1459 patients screened, 598 received one of six treatments: placebo, FF (25 μg, 50 μg, 100 μg or 200 μg) once daily each evening, or fluticasone propionate (FP) 100 μg twice daily for 8 weeks. The primary endpoint was change from baseline in pre-dose evening forced expiratory volume in 1 s (FEV(1))., Results: A dose-response effect was observed for once-daily FF 25-200 μg including (p < 0.001) and excluding placebo (p = 0.03). FF 50-200 μg once daily significantly increased FEV(1) from baseline (p < 0.05 vs placebo), by >200 mL for FF 100 μg and 200 μg. Significant improvements were also achieved for peak expiratory flow, and percentage symptom-free and rescue-free 24 h periods. The magnitude of effect was at least as good as twice-daily FP. Overall, once-daily FF was well tolerated with no systemic corticosteroid effects., Conclusion: FF 50-200 μg/day once daily in the evening demonstrated dose-related efficacy in asthma with 100-200 μg appearing to be the optimal doses for further evaluation. ClinicalTrials.gov: NCT00603382., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

A sensitive method for the determination of fluticasone in plasma was developed using high performance liquid chromatography with tandem mass spectrometric detection, whereas beclomethasone was used as internal standard. The analytes were extracted with a simple liquid-liquid extraction from the plasma samples and separated on an ACE C(18) 50 × 4.6 mm i.d.; 5 μm particle size column with a mobile phase consisting of acetonitrile - 0.01% formic acid (48:52, v/v) at a flow rate of 1 ml/min. Detection was achieved by an Applied Biosystems API 5000 mass spectrometer (LC-MS/MS) set at unit resolution in the multiple reaction monitoring mode. Atmospheric pressure chemical ionization (APCI) was used for ion production. The mean recovery for fluticasone propionate was 85%, with a lower limit of quantification set at 2 pg/mL. The validated analytical method was applied to a bioequivalence study of fluticasone propionate administered by nasal spray formulations in human volunteers., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Prediction of pharmacokinetic (PK) profile for inhaled drugs in humans provides valuable information to aid toxicology safety assessment, evaluate the potential for systemic accumulation on multiple dosing and enable an estimate for the clinical plasma assay requirements. The accuracy in prediction of inhaled human PK profiles for seven inhaled drugs or drug candidates (salmeterol, salbutamol, formoterol, fluticasone propionate, budesonide, CP-325366 and UK-432097) was assessed using rat oratracheal solution and dry powder PK data. The prediction methodology incorporates allometric scaling and mean residence time (MRT) principles with a two compartmental PK approach. Across the range of compounds tested, the prediction of human inhaled maximum concentration (C(max)) and MRT was within 2-fold for 5 of the 7 compounds, providing an accuracy of prediction similar to the current methodologies used to predict human oral C(max) from preclinical data ( De Buck et al. 2007 ). Administering as a dry powder formulation slowed the rat lung absorption rate of the least soluble compound (fluticasone propionate), impacting the prediction of C(max) and MRT. This flags the potential for preclinical studies with dry powder formulations to positively influence predictive accuracy, although further studies with low solubility inhaled drugs are required to confirm this. This study illustrates the value of preclinical assessment of PKs following administration to the lung, and provides a viable means of predicting the human PK profile for inhaled drugs.

Exemestane, irreversible steroidal aromatase inhibitor, acts as a false substrate for aromatase enzyme and significantly lowers circulating estrogen concentrations in postmenopausal women with hormone-sensitive breast cancer. A sensitive bioanalytical method was developed and validated to study pharmacokinetics of exemestane. The method was based on liquid-liquid extraction of exemestane with methyl t-butyl ether followed by reversed-phase liquid chromatography. Positive electrospray ionization tandem mass spectrometry in multiple reaction monitoring mode was applied for detection of exemestane. Anastrozole was used as internal standard. Calibration curve, fitted to 1/x² weighted linear regression model, was linear in the range of 0.1-40.0 ng/mL. Intra-run precision and accuracy were 1.80-3.17% and 103.4-111.5%, respectively. Inter-run precision and accuracy measured within 3 days were 3.37-4.19% and 101.8-109.6%, respectively. Extraction recoveries of exemestane and internal standard were 79.7-86.2% and 82.9-83.6%, respectively. The method was fully validated and may be applied to pharmacokinetic studies in humans after a single dose administration of 25mg exemestane tablets., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Background: Airway absorption and bioavailability of inhaled corticosteroids (ICSs) may be influenced by differences in pharmacokinetic properties such as lipophilicity and patient characteristics such as lung function. This study aimed to further investigate and clarify the distribution of budesonide and fluticasone in patients with severe chronic obstructive pulmonary disease (COPD) by measuring the systemic availability and sputum concentration of budesonide and fluticasone, administered via combination inhalers with the respective long-acting beta2-agonists, formoterol and salmeterol., Methods: This was a randomized, double-blind, double-dummy, two-way crossover, multicenter study. Following a run-in period, 28 patients with severe COPD (mean age 65 years, mean forced expiratory volume in 1 second [FEV1] 37.5% predicted normal) and 27 healthy subjects (mean age 31 years, FEV1 103.3% predicted normal) received two single-dose treatments of budesonide/formoterol (400/12 microg) and salmeterol/fluticasone (50/500 microg), separated by a 4-14-day washout period. ICS concentrations were measured over 10 hours post-inhalation in plasma in all subjects, and over 6 hours in spontaneously expectorated sputum in COPD patients. The primary end point was the area under the curve (AUC) of budesonide and fluticasone plasma concentrations in COPD patients relative to healthy subjects., Results: Mean plasma AUC values were lower in COPD patients versus healthy subjects for budesonide (3.07 microM x hr versus 6.21 microM x hr) and fluticasone (0.84 microM x hr versus 1.50 microM x hr), and the dose-adjusted AUC (geometric mean) ratios in healthy subjects and patients with severe COPD for plasma budesonide and fluticasone were similar (2.02 versus 1.80; primary end point). In COPD patients, the Tmax and the mean residence time in the systemic circulation were shorter for budesonide versus fluticasone (15.5 min versus 50.8 min and 4.41 hrs versus 12.78 hrs, respectively) and Cmax was higher (1.08 microM versus 0.09 microM). The amount of expectorated fluticasone (percentage of estimated lung-deposited dose) in sputum over 6 hours was significantly higher versus budesonide (ratio 5.21; p = 0.006). Both treatments were well tolerated., Conclusion: The relative systemic availabilities of budesonide and fluticasone between patients with severe COPD and healthy subjects were similar. In patients with COPD, a larger fraction of fluticasone was expectorated in the sputum as compared with budesonide., Trial Registration: Trial registration number NCT00379028.

A simple and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been developed and validated for the quantitation of exemestane (Exe) and its main metabolite 17-dihydroexemestane (DhExe) in human plasma. The analytes were extracted by protein precipitation with acetonitrile, containing stable 13C-labelled Exe (13C3-Exe) as internal standard, and measured by LC-MS/MS. The best chromatographic separation of the analytes from the interferences was achieved by using a Phenyl column operating under isocratic regime conditions. The total chromatographic runtime was 5.0 min and the elution of Exe and DhExe occurred at 2.5 min and 2.9 min, respectively. Quantitation was performed by employing the positive electrospray ionization (ESI) technique and multiple reaction monitoring mode (MRM). The monitored precursor to product-ion transitions for Exe, DhExe and 13C3-Exe internal standard were m/z 297.0 --> 120.8, m/z 299.1 --> 134.9 and m/z 300.0 --> 123.2, respectively. The lower limit of quantitation (LLOQ) was 0.1 ng/ml for DhExe and 0.2 ng/ml for Exe. The method was linear up to 36-51 ng/ml with r2 > or = 0.998. The intra- and inter-assay precision were < or = 7.7% and 5.1% for Exe and < or = 8.1 and 4.9% for DhExe while deviations from nominal values were in the 1.5-13.2% and - 9.0-5.8% ranges for Exe and DhExe, respectively. The analytical method resulted robust and suitable for pharmacokinetic monitoring of Exe and its main metabolite during adjuvant therapy in patients with breast cancer., (Copyright 2009 John Wiley & Sons, Ltd.)

This paper reports an LC/MS/MS method for analysis of salemeterol and fluticasone propionate in human plasma based on combined SPE-based extraction and separate LC/MS/MS conditions. Previously reported interaction between analytes was confirmed and eliminated by their separation in the sample preparation step to ensure no negative impact on their quantitation. The method was validated per FDA guidelines in the range of 2.5-500 pg/mL for salmeterol and 5-500 pg/mL for fluticasone propionate. The method is suitable for plasma analysis of combined salmeterol/fluticasone formulation without adverse effects of inter-analyte interactions on quantitation.

The purpose of this study was to investigate the metabolism and disposition of fluticasone furoate, an enhanced-affinity glucocorticoid receptor agonist, in humans. In a two-part, open-label design study, five healthy male subjects received a p.o. dose of 2 mg of [(14)C]fluticasone furoate, followed 4 weeks later by an i.v. dose of 0.25 mg of [(14)C]fluticasone furoate (as a 30-min infusion). Oral absorption was rapid and estimated at approximately 30%, although the oral bioavailability was markedly lower at 1.6%, limited by extensive first-pass metabolism. Plasma clearance was 58.3 l/h, with a volume of distribution of 642 liters and a terminal elimination half-life of 15.3 h. The major circulating component identified in plasma extracts after i.v. and p.o. dosing was unchanged parent compound, with 17beta-carboxylic acid (GW694301X; M10) also being notable after p.o. administration. Mean recovery of radioactivity was approximately 92 and 102% at 216 and 168 h after i.v. and p.o. administration, respectively, with most (at least 90%) recovered in the feces. Fluticasone furoate was extensively metabolized, with only trace amounts of unchanged parent compound observed in feces following either route of administration. The predominant pathway was removal of the S-fluoromethyl carbothioate group to yield GW694301X (M10). Other pathways included oxidative defluorination to yield a hydroxyl at the C6 position. There was no evidence for metabolic loss of the furoate group from fluticasone furoate or any of its metabolites. Evidence presented suggests that enterocytes have a role in the metabolism of unabsorbed fluticasone furoate.

A new and very sensitive analytical method has been developed and validated to jointly determine the anti-inflammatory drug ciclesonide (CIC), its active principle metabolite M1 (CIC-M1) and fluticasone propionate (FP) in human serum, in the low concentration range from 10 to 1000 pg/mL. This was accomplished by high-performance liquid chromatography and tandem mass spectrometry using atmospheric pressure photo ionisation (HPLC-MS/MS with APPI) using 0.5 mL of serum. Serum was mixed with the internal standards (IS) D11-CIC and D11-CIC-M1 and extracted with diisopropylether. A gradient with acetonitrile (containing 10 mM of acetic acid and 10% of acetone) was used. HPLC-MS/MS of the acetic acid adducts of the analytes was performed in negative mode. The novel aspect of this method is that instead of the dopant being introduced directly into the source by means of an external HPLC pump, it was added to the mobile phase. This provided significantly better sensitivity than the usual method of in-source addition of the dopant, and with no loss in HPLC performance. Sensitivity for the analytes was about four times greater than with either APCI or ESI. Validation was performed in three batches. The inter-batch precision (CV) of the quality control samples in human serum ranged from 4.08% to 6.78% for CIC, from 2.57% to 7.74% for CIC-M1, and from 2.38% to 9.61% for FP. The inter-batch accuracy (with reference to the mean value) of the quality control samples in human serum ranged from 99.3% to 110.0% for CIC, from 101.8% to 104.7% for CIC-M1, and from 100.4% to 101.8% for FP. Calibration data and LLOQ data are also presented in this paper. The analytes were stable in human serum over three freeze/thaw cycles, or for 4h at room temperature, or for at least 18 months when stored at below -20 degrees C. This method was used for quantifying the analytes after inhalation of low-mug amounts of the drugs by patients.

Background: Intranasal corticosteroids are recommended as first-line therapy for allergic rhinitis (AR), and because of their pharmacologic class, hypothalamic-pituitary-adrenal (HPA) axis function is evaluated., Objective: To evaluate whether cortisol production was suppressed (as a measure of HPA axis function) by 6 weeks of treatment with fluticasone furoate nasal spray, 110 microg once daily, in patients with perennial AR., Methods: A double-blind, randomized, placebo- and active-controlled (prednisone), parallel-group study. Outpatients aged 12 to 65 years with perennial AR for 2 years or more were from 1 center in the United States and 1 center in Canada. Pharmacodynamic and pharmacokinetic samples were collected during 24-hour domiciled visits (overnight in clinic). Measurements included change from baseline in 24-hour serum cortisol weighted mean and 24-hour urinary free cortisol excretion, total 24-hour urinary free cortisol excretion and 6-beta hydroxycortisol excretion, and plasma concentration of fluticasone furoate., Results: A total of 112 of 183 patients were randomized. Fluticasone furoate was noninferior to placebo with respect to the ratio from baseline in serum cortisol weighted mean (treatment ratio, 0.98; 95% confidence interval, 0.89 to 1.07). In contrast, use of prednisone, 10 mg once daily, significantly reduced the ratio from baseline compared with placebo. Change from baseline in 24-hour urinary cortisol excretion was similar in the fluticasone furoate and placebo groups. Plasma levels of fluticasone furoate were undetectable after 6 weeks of treatment., Conclusion: Fluticasone furoate nasal spray, 110 microg once daily, was not associated with HPA axis suppression in patients 12 years and older with perennial AR.

The systemic exposure of fluticasone propionate with hydrofluoroalkane propellant compared with chlorofluoro-carbon propellant and the effect of fluticasone propionate hydrofluoroalkane on 24-hour urinary cortisol in children aged 4 to 11 years with asthma were evaluated. Study 1 was an open-label, 2-way crossover study in which 16 subjects were randomized to 7.5 days each of fluticasone propionate hydrofluoroalkane 88 mug twice a day or fluticasone propionate chlorofluorocarbon 88 mug twice a day. In study 2, 63 subjects received 13.5 days of placebo followed by 27.5 days of fluticasone propionate hydrofluoroalkane 88 mug twice a day. The main outcome measure for study 1 was the difference between fluticasone propionate hydrofluoroalkane and fluticasone propionate chlorofluorocarbon in fluticasone propionate AUC(last) (area under the plasma fluticasone propionate concentration-time curve from zero up to the last quantifiable plasma concentration), and for study 2, 24-hour overnight urinary cortisol excretion. In study 1, fluticasone propionate systemic exposure was significantly lower (55%) with hydrofluoroalkane metered dose inhaler compared with chlorofluorocarbon metered dose inhaler. Study 2 showed no statistically significant changes in 24-hour overnight urinary cortisol excretion and no relationship to fluticasone propionate systemic exposure at this dose. The results of these 2 studies showed that in children aged 4 to 11 years with asthma, fluticasone propionate hydrofluoroalkane has lower systemic exposure compared with chlorofluorocarbon and no hypothalamic-pituitary-adrenal axis effects as measured by 24-hour urinary cortisol excretion.

Aims: To determine whether and to what extent bronchoconstriction affects plasma concentrations of fluticasone and budesonide following inhalation., Methods: Twenty people with mild asthma inhaled 1000 microg fluticasone (Accuhaler) plus 800 microg budesonide (Turbohaler) on two visits. On one occasion, prior to drug inhalation, FEV(1) was decreased by at least 25% using inhaled methacholine. Plasma drug concentrations were measured for each drug over 5 h and area under the plasma concentration-time curve (AUC(0,5 h)) compared between visits., Results: The mean difference in FEV(1) prior to drug inhalation on the 2 days was 33%. AUC(0,5 h) values for fluticasone and budesonide were lower by a median of 60% (IQR 36-75) and 29% (IQR 2-44), respectively, when administered following bronchoconstriction; the reduction was greater for fluticasone than for budesonide, P = 0.007., Conclusions: The lower plasma concentrations of fluticasone and, to a lesser extent, budesonide seen when the drugs were inhaled following induced bronchoconstriction, is likely to reflect variations that will occur with fluctuations in airway caliber in asthma.

Surveillance of illegal use of steroids hormones in cattle breeding is a key issue to preserve human health. To this purpose, an integrated approach has been developed for the analysis of plasma and urine from calves treated orally with a single dose of a combination of the androgenic steroids boldenone and boldione. A quantitative estimation of steroid hormones was obtained by LC-APCI-Q-MS/MS analysis of plasma and urine samples obtained at various times up to 36 and 24 h after treatment, respectively. These experiments demonstrated that boldione was never found, while boldenone alpha- and beta-epimers were detected in plasma and urine only within 2 and 24 h after drug administration, respectively. Parallel proteomic analysis of plasma samples was obtained by combined 2-DE, MALDI-TOF-MS and muLC-ESI-IT-MS/MS procedures. A specific protein, poorly represented in normal plasma samples collected before treatment, was found upregulated even 36 h after hormone treatment. Extensive mass mapping experiments proved this component as an N-terminal truncated form of apolipoprotein A1 (ApoA1), a protein involved in cholesterol transport. The expression profile of ApoA1 analysed by Western blot analysis confirmed a significant and time dependent increase of this ApoA1 fragment. Then, provided that further experiments performed with a growth-promoting schedule will confirm these preliminary findings, truncated ApoA1 may be proposed as a candidate biomarker for steroid boldenone and possibly other anabolic androgens misuse in cattle veal calves, when no traces of hormones are detectable in plasma or urine.

Background: Fluticasone furoate (drug code GW685698) is an enhanced-affinity glucocorticoid that has been developed for the treatment of allergic rhinitis., Objectives: The objectives of this study were to estimate the absolute bioavailability of fluticasone furoate nasal spray and to describe the intranasal (IN) and IV pharmacokinetics of fluticasone furoate in healthy subjects., Methods: This was a single-center, randomized, open label, 2-period crossover study. Healthy male and female subjects were randomized to receive supra-therapeutic doses of fluticasone furoate 880 microg IN qSh for 10 doses in 1 treatment period, and a single IV dose of 250 pg fluticasone furoate given as an infusion over 20 minutes in the other treatment period. Each treatment period was separated by a 4- to 5-day washout period. Blood sampling was carried out over 8 hours following the final IN dose and 24 hours following the IV dose to determine plasma fluticasone furoate concentrations. Plasma samples were analyzed for fluticasone furoate using online solid-phase extraction with high-performance liquid chromatography with tandem mass-spectrometric detection. The lower limit of quantification was 10 pg/mL. The sample size was based primarily on logistical considerations. Sample-size sensitivity was assessed by estimating the 90% CI for the absolute bioavailability of IN fluticasone furoate, based on different estimated bioavailabilities and within-subject SDs. The following pharmacokinetic parameters were derived: IN administration: AUC from time 0 to the end of the dosing interval (AUC(0-tau)), AUC(0-t), C(max), and T(max); IV administration: AUC(0-infinity), AUC(0-t), t(1/2), C(max), T(max), total systemic clearance, and volume of distribution at steady state., Results: A total of 16 subjects were included in the study. Their mean age was 27.8 years (range, 19-45 years), and their mean body weight was 72.84 kg (range, 55.3-97.2 kg). The geometric mean AUC(0-tau) for 880 microg IN was 74.9 pg x mL/h and geometric mean AUC(0-infinity) for 250 microg IV was 4259 pg x mL/h. The geometric mean of the absolute bioavailability of fluticasone furoate nasal spray in these healthy subjects was 0.50% (90% CI, 0.34%-0.74%). The administration of large doses by the IN route did not elicit clinical concern. Three (19%) of 16 subjects reported adverse events (AEs) during the IN administration period, with 2 subjects experiencing dizziness and 1, toothache. Five (31%) subjects reported AEs during the IV administration period, with 3 subjects experiencing infusion-site or IV catheter-related events; 1 subject, dizziness; and 1 subject, headache., Conclusions: The geometric mean of the absolute bioavailability of fluticasone furoate 880 microg IN qSh for 10 doses in these healthy subjects was low--0.50%.

Objective: To evaluate the efficacy and tolerability of fluticasone propionate (FP) hydrofluoroalkane (HFA) in children age 1 to < 4 years with asthma., Study Design: Children were assigned (2:1) to receive FP HFA 88 mug (n = 239) or placebo HFA (n = 120) twice daily through a metered-dose inhaler with a valved holding chamber and attached facemask for 12 weeks. The primary efficacy measure was mean percent change from baseline to endpoint in 24-hour daily (composite of daytime and nighttime) asthma symptom scores., Results: The FP-treated children had significantly greater (P < or = .05) reductions in 24-hour daily asthma symptom scores (-53.9% vs -44.1%) and nighttime symptom scores over the entire treatment period compared with the placebo group. Daytime asthma symptom scores and albuterol use were slightly more decreased with FP than with placebo; however, the differences were not statistically significant. Increases in the percentage of symptom-free days were comparable. The percentage of patients who experienced at least 1 adverse event was similar in the 2 groups. Baseline median urinary cortisol excretion values were comparable between the groups, and there was little change from baseline at endpoint. FP plasma concentrations demonstrated that systemic exposure was low., Conclusions: FP HFA 88 mug twice daily was effective and well tolerated in pre-school-age children with asthma.

The manufacture of micro-HPLC columns with combined stationary phases, a body of 3.5-microm XTerra-C18 particles, and poly(styrene-divinylbenzene) (PS-DVB) frits is described in detail. The efficiency of the columns was assessed by rapid separation of neutral and acid compound mixtures. Direct analysis of some pharmaceuticals in plasma resulted in lower limits of detection (LOD) for salmeterol xinofate of 12.5 nanograms on-column.

Background: Current asthma guidelines recommend inhaled glucocorticoids administered via pressurized metered-dose inhaler (MDI) with a holding chamber as the preferred therapy for young children with asthma., Objective: To evaluate the efficacy and safety of fluticasone propionate chlorofluorocarbon MDI use in preschool-aged children with asthma., Methods: Randomized, double-blind, placebo-controlled, parallel-group study of 332 children aged 24 to 47 months with asthma. Fluticasone propionate chlorofluorocarbon, 44 or 88 microg twice daily, or placebo (chlorofluorocarbon propellant alone) administered for 12 weeks via MDI with a valved holding chamber and an attached face mask. The primary efficacy measure was average change in 24-hour daily asthma symptom scores. Safety assessments included adverse events, 12-hour urinary cortisol excretion, and growth., Results: Treatment failure (ie, asthma exacerbation) occurred in approximately half as many fluticasone propionate-treated patients (13%-14%) as placebo-treated patients (24%). Compared with placebo users, patients treated with fluticasone propionate, 88 microg twice daily, had a 13% greater improvement in the mean proportion of symptom- and albuterol-free days (P = .02); asthma symptom scores and albuterol use were also significantly reduced. Patients treated with fluticasone propionate, 44 microg twice daily, had greater improvements than placebo-treated patients; however, differences did not reach statistical significance. At end point, the growth velocities of fluticasone propionate-treated patients were within the range of those of placebo-treated patients. No clinically relevant changes in 12-hour overnight urinary cortisol excretion were observed., Conclusion: Compared with placebo use, fluticasone propionate, 88 microg administered twice daily, significantly reduced asthma exacerbations, asthma symptoms, and rescue albuterol use and was well tolerated, with no clinically relevant systemic effects, as measured by growth velocity or 12-hour urinary cortisol excretion levels.

Background: Inhaled corticosteroids (ICSs) delivered by metered-dose inhalers that contain chlorofluorocarbon propellants are being discontinued because of the harmful effects of chlorofluorocarbon on the ozone layer. Therefore, some metered-dose inhaler products are being reformulated with "ozone-friendly" hydrofluoroalkane propellants., Objective: To evaluate treatment with fluticasone propionate hydrofluoroalkane inhalation aerosol, 88, 220, and 440 microg twice daily, vs placebo in patients with asthma receiving an ICS., Methods: Randomized, double-blind, parallel-group, 12-week study., Results: Mean morning predose percent predicted forced expiratory volume in 1 second increased by 2.2%, 3.2%, and 4.6% in the fluticasone propionate, 88-, 220-, and 440-microg twice-daily, groups, respectively, compared with an 8.3% decrease for placebo (P < .001 vs placebo for all groups). Secondary pulmonary function end points and asthma symptoms showed similar improvements compared with placebo. Discontinuation from the study due to lack of efficacy was 50% in the placebo group and 11%, 10%, and 6% in the fluticasone propionate, 88-, 220-, and 440-microg twice-daily, groups, respectively. At week 12, the probability of remaining in the study was 0.89, 0.90, and 0.94 for the fluticasone propionate, 88-, 220-, and 440-microg twice-daily, groups, respectively, vs 0.45 for the placebo group (P < .001 for all). Changes in 24-hour urinary cortisol excretion rates were similar among treatment groups., Conclusions: Fluticasone propionate hydrofluoroalkane, previously shown to be a clinically suitable alternative to fluticasone propionate chlorofluorocarbon, was effective and well tolerated. The ability to switch from fluticasone propionate chlorofluorocarbon and other chlorofluorocarbon-containing ICSs to fluticasone propionate hydrofluoroalkane without sacrificing asthma control or tolerability will facilitate a smooth transition to this nonchlorofluorocarbon-containing medicinal.

Background: Inhaled corticosteroids are the preferred therapy in persistent asthma. Dry powder inhalers (DPIs) generate a larger particle size compared with metered-dose inhalers (MDIs), which affects pulmonary deposition, bioavailability, and subsequent systemic effects of fluticasone propionate (fluticasone)., Objective: To examine the relationship of fluticasone pharmacokinetics and cortisol suppression for 2 fluticasone formulations (DPI and MDI) administered in adults over 1-week and 6-week treatment periods., Methods: Two previous studies conducted in adults by the Asthma Clinical Research Network examined relative efficacy and systemic effect of fluticasone from MDI and DPI. Sample sets (n=33) were analyzed for fluticasone after administration of 352 microg from the MDI, and 400 microg from the DPI formulation, twice daily, after a 1-week treatment period. The second study's sample sets (n=9) were analyzed for fluticasone after 6 weeks therapy at 352 microg twice daily from the MDI formulation, allowing achievement of steady state., Results: ANOVA revealed a significant trend of increasing fluticasone area under the curve from 0 to time t (AUC(0-->t)) when comparing DPI with MDI for 1 week with MDI for 6 weeks (P<.0001). Similarly, ANOVA revealed increasing cortisol suppression between these groups (P=.007). Linear regression demonstrated that increasing fluticasone AUC(0-->t) was significantly correlated with cortisol suppression (P<.0001; r(2)=0.41). MDI for 6 weeks showed increasing fluticasone AUC (P=.0008, t test) compared with MDI for 1 week, suggesting accumulation., Conclusion: Fluticasone plasma concentrations are significantly greater after MDI compared with DPI, and cortisol suppression is associated with fluticasone plasma concentrations. Accumulation of fluticasone concentrations suggests that time to steady state exceeds 1 week of treatment with MDI.

Objective: Reports characterizing the pharmacokinetics of inhaled fluticasone propionate (FP) using compartmental approaches have suggested that the absorption of FP into the systemic circulation is rapid with a half-life of approximately 10 min. We believe that this is a classical case of misassignment of the pharmacokinetic parameter estimates, a problem often encountered while modeling pharmacokinetic data. The objective of this study was to illustrate and analyze this problem using actual blood level data of FP obtained in 14 healthy subjects., Materials and Methods: Serum concentration-time data of FP were obtained from a double-blind, randomized study involving single and multiple twice-daily inhalations of 500 microg via a dry powder device, Diskus. The profiles were fitted using one- and two-compartment pharmacokinetic models with first order absorption. Various permutations of the resulting exponential rate constants were analyzed to determine the combination that was most consistent with the underlying physical process., Results: The two-compartment body model with first order absorption gave excellent fits for the observed FP concentrations after both single and multiple dosing. Even though peak levels were reached relatively early (30 - 90 min) after inhalation, the combination that most appropriately described the underlying process was alpha > Ka > beta, i.e. slow absorption, rapid distribution and slower elimination kinetics. The absorption, distribution and elimination half-lives resulted to be 3.8 h, 9.9 min and 13.6 h, respectively, consistent with the high lipophilicity and sustained dissolution characteristics observed in vitro., Conclusions: Analysis of FP pharmacokinetics after inhalation represents a classical case of potential misassignment of the exponential rate constants, which if ignored, could lead to erroneous interpretations regarding the underlying process. The study also elucidates the pitfall of using t(max) to calculate absorption rate.

We have developed biologically stable semisynthetic viridins as inhibitors of phosphoinositide (PtdIns)-3-kinases. The most active compound was PX-866 (acetic acid (1S,4E,10R,11R,13S,14R)-[4-diallylaminomethylene-6-hydroxy-1-methoxymethyl-10,13-dimethyl-3,7,17-trioxo-1,3,4,7,10,11,12,13,14,15,16,17-dodecahydro-2-oxa-cyclopenta[a]phenanthren-11-yl ester), which inhibited purified PtdIns-3-kinase with an IC50 of 0.1 nmol/L and PtdIns-3-kinase signaling measured by phospho-Ser473-Akt levels in HT-29 colon cancer cells with an IC50 of 20 nmol/L. PX-866 administered to mice at 10 mg/kg inhibited phospho-Ser473-Akt in HT-29 colon tumor xenografts up to 80% with recovery taking >48 hours after p.o. administration but more rapidly after i.v. or i.p. administration. PX-866 was eliminated from mouse plasma with a half-life of 18 minutes and a clearance of 360 mL/min/kg following i.v. administration and, when administered i.p. or p.o., showed first-pass metabolism with sequential N-deallylation. Synthetic standards of the N-deallylated metabolites of PX-866 inhibited PtdIns-3-kinase at low nanomolar per liter concentrations. PX-866 exhibited in vivo antitumor activity against s.c. OvCar-3 human ovarian cancer and A-549 human lung cancer xenografts in immunodeficient mice with log cell kills up to 1.2. PX-866 also increased the antitumor activity of cisplatin against A-549 xenografts and radiation treatment against OvCar-3 xenografts. The results show that PX-866 is a biologically stable broad-spectrum PtdIns-3-kinase inhibitor with good pharmacokinetics that causes prolonged inhibition of PtdIns-3-kinase signaling in human tumor xenografts. PX-866 exhibits single agent in vivo antitumor activity and increases the antitumor effects of cisplatin and radiation treatment.

Loteprednol etabonate (LE) is a glucocorticoid soft drug that is currently in development for intranasal use. The main objectives of this study were to examine the pharmacokinetics and potential effects on systemic cortisol of two intranasal suspension formulations of LE and to compare these findings with placebo and fluticasone propionate (FP, Flonase) control treatments. In this randomized, double-blind (except for FP), parallel-group study (n = 8/group), all subjects received for 14 days once daily in the morning two puffs of the following nasal spray formulations into each nostril: LE 0.1% (400 microg/day), LE 0.2% (800 microg/day), FP 0.05% (200 microg/day), and placebo. Drug trough levels were determined on days 1, 5, 12, 13, and 14, and a full pharmacokinetic profile was established on day 14, and 24-hour serum cortisol profiles were assessed prior to treatment (i.e., at baseline) and after the last dose. All subjects completed the protocol without treatment-emergent adverse findings. All formulations were rapidly absorbed (t(max) less than 1 h). The rather short mean terminal half-lives of 2.2 +/- 1.5 hours and 1.8 +/- 1.0 hours for LE 400 microg and LE 800 microg, respectively, and 4.2 +/- 1.8 hours for the 200-microg FP treatment explained the lack of any accumulation. Mean peak concentrations (C(max)) were 139 +/- 57 pg/mL with LE 400 microg and 164 +/- 54 pg/mL with LE 800 microg and thus fairly independent from dose. The 200-microg FP treatment resulted in a C(max) of only 15.5 +/- 5.9 pg/mL. Mean measured AUC(0-t) values (193 +/- 87 pg/h/mL(-1), 300 +/- 183 pg/h/mL(-1), and 40 +/- 34 pg/h/mL(-1) for LE 400 microg, LE 800 microg, and FP 200 microg, respectively) showed high variability and suggested nonlinear pharmacokinetics for the LE formulations, indicative of a less complete systemic uptake of LE from the 0.2% concentration. None of the treatments (LE 400 microg, LE 800 microg, and FP 200 microg) showed evidence for serum cortisol suppression when compared with placebo, respectively. The uptake and systemic exposure appears less complete from the 0.2% LE concentration, which principally favors this formulation for further clinical development.

Study Objective: To investigate the effect of the nasal corticosteroid fluticasone propionate on the bioavailability and pharmacokinetics of single-dose intranasal hydromorphone hydrochloride in patients with allergic rhinitis., Design: Randomized, three-way, crossover pharmacokinetic study., Setting: University clinical research unit., Patients: Twelve patients with allergic rhinitis., Intervention: Hydromorphone hydrochloride 2.0 mg was administered by intravenous infusion (treatment A), intranasal spray without allergic rhinitis treatment (treatment B), and intranasal spray after 6 days of fluticasone propionate (treatment C). Blood samples were collected serially from 0-16 hours., Measurements and Main Results: Pharmacokinetic parameters were determined by noncompartmental methods. An analysis of variance (ANOVA) model was used for statistical analysis. Mean (% coefficient of variation) absolute bioavailability of intranasal hydromorphone was 51.9% (28.2) and 46.9% (30.3) in patients with allergic rhinitis with and without treatment with fluticasone propionate, respectively. Mean maximum concentration (Cmax) values were 3.02 and 3.56 ng/ml, respectively. No statistical differences in Cmax and area under the concentration versus time curve were detected between intranasal treatments. Bioavailability values for both intranasal treatments were lower than those in healthy volunteers (57%). Median time to Cmax (Tmax) values were significantly different (p=0.02) for treatments B and C (15 and 30 min, respectively) using rank-transformed Tmax for ANOVA. Adverse effects were consistent with known effects of hydromorphone administered by other routes, with the exception of bad taste after intranasal administration., Conclusion: Hydromorphone was rapidly absorbed after nasal administration, with maximum concentrations occurring for most subjects within 30 minutes. Allergic rhinitis may affect pain management strategies for intranasal hydromorphone, with a delay in onset of action for patients treated with fluticasone propionate.

Objective: Some patients develop side-effects even on relatively low doses of topically administered glucocorticoids (GCs), while others appear to be less sensitive to GCs. We have developed and validated a bioassay which can measure glucocorticoid bioavailability directly from small amounts of human serum to help elucidate underlying mechanisms., Methods: We have stably transfected the human embryonic kidney cell line HEK293 with a plasmid expressing the glucocorticoid receptor, and a plasmid containing the luciferase gene preceded by three concatenated steroid response elements, bringing luciferase expression under control of the liganded glucocorticoid receptor., Results: The assay, with an intra- and interassay coefficient of variance (CV) better than 10%, showed the expected difference in potency between different GCs (fluticasone propionate > budesonide > dexamethasone > hydrocortisone). No cross-reactivity was detected with other steroid hormones such as progesterone, testosterone and oestradiol. The bioassay easily detects the rise and subsequent fall of bioavailable GCs in human serum following ingestion of only 0.5 mg dexamethasone, and clearly reflects the diurnal cortisol rhythm. Moreover, systemic availability following inhalation of 2 x 250 micro g fluticasone propionate using a pressure dose inhaler could be demonstrated., Conclusions: This assay can be used to determine levels of bioavailable GCs in serum, both endogenous and administered, and thus may help in optimizing treatment regimens. The small amount of serum needed to perform an analysis makes this assay applicable even to infants.