Impact of CYP3A5 Polymorphisms on Pediatric Asthma Outcomes.

Genetic variation among inhaled corticosteroid (ICS)-metabolizing enzymes may affect asthma control, but evidence is limited. This study tested the hypothesis that single-nucleotide polymorphisms (SNPs) in Cytochrome P450 3A5 (CYP3A5) would affect asthma outcomes. Patients aged 2-18 years with persistent asthma were recruited to use the electronic AsthmaTracker (e-AT), a self-monitoring tool that records weekly asthma control, medication use, and asthma outcomes. A subset of patients provided saliva samples for SNP analysis and participated in a pharmacokinetic study. Multivariable regression analysis adjusted for age, sex, race, and ethnicity was used to evaluate the impact of CYP3A5 SNPs on asthma outcomes, including asthma control (measured using the asthma symptom tracker, a modified version of the asthma control test or ACT), exacerbations, and hospital admissions. Plasma corticosteroid and cortisol concentrations post-ICS dosing were also assayed using liquid chromatography-tandem mass spectrometry. Of the 751 patients using the e-AT, 166 (22.1%) provided saliva samples and 16 completed the PK study. The e-AT cohort was 65.1% male, and 89.6% White, 6.0% Native Hawaiian, 1.2% Black, 1.2% Native American, 1.8% of unknown race, and 15.7% Hispanic/Latino; the median age was 8.35 (IQR: 5.51-11.3) years. CYP3A5*3/*3 frequency was 75.8% in White subjects, 50% in Native Hawaiians and 76.9% in Hispanic/Latino subjects. Compared with CYP3A5*3/*3, the CYP3A5*1/*x genotype was associated with reduced weekly asthma control (OR: 0.98; 95% CI: 0.97-0.98; p < 0.001), increased exacerbations (OR: 6.43; 95% CI: 4.56-9.07; p < 0.001), and increased asthma hospitalizations (OR: 1.66; 95% CI: 1.43-1.93; p < 0.001); analysis of 3/*3, *1/*1 and *1/*3 separately showed an allelic copy effect. Finally, PK analysis post-ICS dosing suggested muted changes in cortisol concentrations for patients with the CYP3A5*3/*3 genotype, as opposed to an effect on ICS PK. Detection of CYP3A5*3/3, CYPA35*1/*3, and CYP3A5*1/*1 could impact inhaled steroid treatment strategies for asthma in the future.

Transitioning from Basic toward Systems Pharmacodynamic Models: Lessons from Corticosteroids.

Technology in bioanalysis, -omics, and computation have evolved over the past half century to allow for comprehensive assessments of the molecular to whole body pharmacology of diverse corticosteroids. Such studies have advanced pharmacokinetic and pharmacodynamic (PK/PD) concepts and models that often generalize across various classes of drugs. These models encompass the "pillars" of pharmacology, namely PK and target drug exposure, the mass-law interactions of drugs with receptors/targets, and the consequent turnover and homeostatic control of genes, biomarkers, physiologic responses, and disease symptoms. Pharmacokinetic methodology utilizes noncompartmental, compartmental, reversible, physiologic [full physiologically based pharmacokinetic (PBPK) and minimal PBPK], and target-mediated drug disposition models using a growing array of pharmacometric considerations and software. Basic PK/PD models have emerged (simple direct, biophase, slow receptor binding, indirect response, irreversible, turnover with inactivation, and transduction models) that place emphasis on parsimony, are mechanistic in nature, and serve as highly useful "top-down" methods of quantitating the actions of diverse drugs. These are often components of more complex quantitative systems pharmacology (QSP) models that explain the array of responses to various drugs, including corticosteroids. Progressively deeper mechanistic appreciation of PBPK, drug-target interactions, and systems physiology from the molecular (genomic, proteomic, metabolomic) to cellular to whole body levels provides the foundation for enhanced PK/PD to comprehensive QSP models. Our research based on cell, animal, clinical, and theoretical studies with corticosteroids have provided ideas and quantitative methods that have broadly advanced the fields of PK/PD and QSP modeling and illustrates the transition toward a global, systems understanding of actions of diverse drugs. SIGNIFICANCE STATEMENT: Over the past half century, pharmacokinetics (PK) and pharmacokinetics/pharmacodynamics (PK/PD) have evolved to provide an array of mechanism-based models that help quantitate the disposition and actions of most drugs. We describe how many basic PK and PK/PD model components were identified and often applied to the diverse properties of corticosteroids (CS). The CS have complications in disposition and a wide array of simple receptor-to complex gene-mediated actions in multiple organs. Continued assessments of such complexities have offered opportunities to develop models ranging from simple PK to enhanced PK/PD to quantitative systems pharmacology (QSP) that help explain therapeutic and adverse CS effects. Concurrent development of state-of-the-art PK, PK/PD, and QSP models are described alongside experimental studies that revealed diverse CS actions.

Antenatal corticosteroids: a reappraisal of the drug formulation and dose.

We review the history of antenatal corticosteroid therapy (ACS) and present recent experimental data to demonstrate that this, one of the pillars of perinatal care, has been inadequately evaluated to minimize fetal exposure to these powerful medications. There have been concerns since 1972 that fetal exposures to ACS convey risk. However, this developmental modulator, with its multiple widespread biologic effects, has not been evaluated for drug choice, dose, or duration of treatment, despite over 30 randomized trials. The treatment used in the United States is two intramuscular doses of a mixture of 6 mg betamethasone phosphate (Beta P) and 6 mg betamethasone acetate (Beta Ac). To optimize outcomes with ACS, the goal should be to minimize fetal drug exposure. We have determined that the minimum exposure needed for fetal lung maturation in sheep, monkeys, and humans (based on published cord blood corticosteroid concentrations) is about 1 ng/ml for a 48-h continuous exposure, far lower than the concentration reached by the current dosing. Because the slowly released Beta Ac results in prolonged fetal exposure, a drug containing Beta Ac is not ideal for ACS use. IMPACT: Using sheep and monkey models, we have defined the minimum corticosteroid exposure for a fetal lung maturation. These results should generate new clinical trials of antenatal corticosteroids (ACS) at much lower fetal exposures to ACS, possibly given orally, with fewer risks for the fetus.

Topical corticosteroid vehicle composition and implications for clinical practice.

This narrative review highlights the therapeutic significance of topical corticosteroid (TCS) vehicles and provides subsequent guidance to improve clinical and research outcomes. A greater understanding of the relationship between the topical vehicle, corticosteroid and skin is needed to ensure safer, more effective treatment for patients. Topical vehicles are not inert and can affect TCS bioavailability, due to the ability of their composition to positively or negatively influence skin status and change the physiochemical characteristics of an inherent corticosteroid. However, this principle is not commonly understood, and has contributed to inconsistencies in potency classification systems. This review provides an insight into the research methods and standardization needed to determine TCS product bioavailability. It identifies formulation components responsible for vehicle composition that underpin the quality, stability, compounding and functionalities of vehicle ingredients. This helps to contextualize how topical vehicles can be responsible for clinically significant effects, and how their composition gives products unique properties. In turn, this facilitates a more in-depth understanding of which resources offer information to inform the best selection of TCS products and why products should be prescribed by brand or manufacturer. This review will better equip clinicians and formulary teams to appraise products. It will also inform prescribing of Specials and why products should not be manipulated. The recommendations, accompanied by patient perspectives on using TCS products, assist clinical decision-making. They also identify the need for research into concomitant application of TCS products with other topical therapies.

Population pharmacokinetic modeling of intramuscular and oral dexamethasone and betamethasone in Indian women.

Population analysis of pharmacokinetic data for five differing dosage forms and routes for dexamethasone and betamethasone in 48 healthy nonpregnant Indian women was performed that accounted for a partial and complex cross-over design. Single doses of 6 mg dexamethasone phosphate (DEX-P), betamethasone phosphate (BET-P), or 1:1 mixture of betamethasone phosphate and acetate (BET-PA) were administered orally (PO) or intramuscularly (IM). Plasma concentrations collected for two periods over 96 h were described with a two-compartment model with differing PO and IM first-order absorption inputs. Clearances and volumes were divided by the IM bioavailability [Formula: see text]. The homogeneous ages, body weights, and ethnicity of the women obviated covariate analysis. Parameter estimates were obtained by the Laplace estimation method implemented in NONMEM 7.4. Typical values for dexamethasone were clearance ([Formula: see text] of 9.29 L/h, steady-state volume ([Formula: see text] of 56.4 L, IM absorption constant [Formula: see text] of 0.460 1/h and oral absorption constant ([Formula: see text] of 0.936 1/h. Betamethasone parameters were CL/FIM of 5.95 L/h, [Formula: see text] of 72.4 L, [Formula: see text] of 0.971 1/h, and [Formula: see text] of 1.21 1/h. The PO to IM F values were close to 1.0 for both drugs. The terminal half-lives averaged about 7.5 h for DEX, 17 h for BET, and 78 h for BET from BET-PA with the latter reflecting very slow release of BET from the acetate ester. Overall, BET exhibited slower clearance, larger volume of distribution, faster absorption, and longer persistence than DEX. These data may be useful in considering exposures when substituting one form of corticosteroid for another.

Genetic variants in toll-like receptor 4 are associated with lack of steroid-responsiveness in pediatric ITP patients.

Although the most common front-line therapies for immune thrombocytopenia (ITP) have been in use for decades, it is still not possible to predict an individual patient's clinical course and response to therapy. Patients are managed with a trial-and-error approach and often suffer side effects of therapies which could have been avoided if response prediction were possible. Corticosteroids are the most frequently used upfront therapy for adults and children with ITP. Our group performed whole exome sequencing on a cohort of pediatric ITP patients, and identified two missense single nucleotide variants (SNV) in Toll-like receptor 4 (TLR4). These coding variants in TLR4 had an increased frequency in Caucasian patients with poor response to upfront steroid therapy. Both TLR4 (D299G; rs4986790) and TLR4 (T399I; rs4986791) had a minor allele frequency (MAF) of 20.7% in those patients unresponsive to steroids, but were present at lower allele frequencies of 2.3% and 3.4% in responders respectively (P < .001). These findings were consistent with the trend identified in an independent cohort of pediatric ITP patients treated with corticosteroids who underwent direct genotyping for both SNVs. This study identified two candidate genetic variants in two unique cohorts of ITP patients which may contribute to steroid response and have prognostic implications for treatment response in ITP.

Optimal Management of Corticosteroids in Patients with Intracranial Malignancies.

OPINION STATEMENT: Corticosteroids have been essential in the management of brain tumor patients for decades, primarily for the treatment of peritumoral cerebral edema and its associated neurologic deficits. Dexamethasone is the drug of choice with standard practice being administration up to four times per day, however, because of its long biologic half-life and high potency, once or twice a day dosing is likely adequate in patients without elevated intracranial pressure. The length of corticosteroid treatment should be limited to the shortest period of time to minimize the risk of potential toxicities that can significantly affect quality of life, as well as to avoid a possible detrimental impact on survival in high-grade glioma patients and abrogation of the effect of immunotherapy. Agents such as bevacizumab should be considered in patients who are unable to wean completely off of steroids as well as those who have symptomatic edema and are on immunotherapy. Several other agents have been studied without much success. An increased understanding of the complex pathophysiology of peritumoral vasogenic edema is critically needed to discover new agents that are safer and more effective.

Cross-sectional CT Assessment of the Extent of Injectate Spread at CT Fluoroscopy-guided Cervical Epidural Interlaminar Steroid Injections.

Background Previous studies analyzed contrast agent spread during cervical interlaminar epidural steroid injections (CILESIs) by using planar fluoroscopy and reported wide variance of the rate of spread to the ventral epidural space (VES). Cross-sectional CT allows for direct viewing of contrast agent in the VES, providing improved spread assessment and thereby informing needle placement decisions when targeting pain generators. Purpose To determine the extent of injectate spread at CT fluoroscopy-guided CILESI, with particular attention to the VES and bilateral neuroforamina, by using cross-sectional CT. Materials and Methods This study reviewed 83 consecutive CT fluoroscopy-guided CILESIs at which a postprocedural cervical spine CT was performed (June 2016 to December 2017). All procedures used the same injectate (2 mL corticosteroid, 3 mL contrast agent). Postprocedural CT scans were reviewed for the presence of contrast within the VES, dorsal epidural space, ipsilateral neuroforamen, and contralateral neuroforamen in every cervical interlaminar level. Descriptive data are presented as frequencies or means. McNemar tests or hierarchical logistic models were used to assess associations between covariates and contrast agent spread to particular locations. Results The study cohort included 73 individual patients (59% women; 43 of 73) (mean patient age, 57.6 years ± 11.5 [standard deviation]). Mean number of levels of cranial spread were 0.6 level for VES, 1.9 levels for contralateral neuroforamen, 2.1 levels for ipsilateral neuroforamen, and 3 levels for dorsal epidural space. No VES spread in any level was found with 35% (29 of 83) of injections. VES spread was more likely to occur in the level of needle placement (43%; 36 of 83) than in other interlaminar levels (19.5%; 97 of 498; P < .001). Spread was more likely to occur in the neuroforamen ipsilateral to the needle approach compared with contralateral (P < .001). Conclusion Cervical interlaminar epidural steroid injections have injectate spreads with a mean of less than one level cranially in the ventral epidural space (VES) and approximately two levels in the neuroforamen. VES spread occurs more frequently at the level of needle placement and within the ipsilateral neuroforamen. © RSNA, 2019.

Pharmacokinetics and pharmacodynamics of inhaled corticosteroids for asthma treatment.

The differences in the pharmacokinetic (PK) characteristics of inhaled corticosteroids (ICSs) critically influence the profile of each of them, but also the significant differences in glucocorticoid receptor selectivity, potency, and physicochemical properties are critical in defining the pharmacodynamic (PD) profile of an ICS. The PK and PD properties of ICSs used in asthma and the importance of their interrelationship have been reviewed. The differences among the ICSs in PK and PD must be considered when an ICS should be prescribed to an asthmatic patient because a better understanding of the PK/PD interrelationship of ICSs could be important to better fit with the between-patient variability and within-patient repeatability in the response to ICSs that often complicate the therapeutic approach to the asthmatic patient. The role of the device in influencing the PK profile of an ICS must be always considered because it is crucial. Also patient-related factors and disease severity affect pulmonary deposition of ICS.

Bioequivalence Study Methods with Pharmacokinetic Endpoints for Topical Ophthalmic Corticosteroid Suspensions and Effects of Subject Demographics.

PURPOSE: To establish bioequivalence for topical ophthalmic corticosteroid suspensions, some of U.S. product-specific guidances (PSGs) for generic drug products recommend evaluation of aqueous humor (AH) pharmacokinetics (PK). However, the AH PK study is complex because the relationships among AH PK, subject demographics, ocular anatomy, physiology and the compounds' physicochemical characteristics are not well understood. The objective of this research is to provide an overview of the in vivo human AH studies submitted to the U.S. Food and Drug Administration (FDA) for ophthalmic corticosteroid suspensions and to investigate the impact of subject demographics on the human AH PK. METHODS: We summarized demographic data, sampling time points, sample size per time point and PK parameters to investigate correlations in the studies submitted to the FDA. RESULTS: In the evaluation of subject-specific covariates, the area under the concentration-time curves (AUC) and maximum concentrations (Cmax) were significantly different among ethnicities and age groups. Gender was not primarily associated with differences in AH PK. CONCLUSIONS: Our results suggest that the difference in ethnicity and age of the study population play an important role in the AH PK profiles of topical ophthalmic corticosteroid suspensions. Considering the subject-specific covariate effects in designing bioequivalence studies with AH PK endpoints could reduce bias from covariate imbalance and help identify true effects of formulation differences.

Revisiting FDA's 1995 Guidance on Bioequivalence Establishment of Topical Dermatologic Corticosteroids: New Research Based Recommendations.

PURPOSE: As per the US FDA guidance issued on June 2, 1995, the establishment of bioequivalence for topical dermatologic corticosteroids is based on comparing the pharmacodynamic (PD) effects of Test and Reference products at the dose duration corresponding to the population ED50, determined either by naïve pooled data or nonlinear mixed effect modeling (NLME). The guidance was introduced using a study case example where the expectation maximization (EM) NLME algorithm, as implemented in P-PHARM®, was used. Although EM methods are relatively common, other methods such as the First-Order Conditional Estimation (FOCE) as implemented in the NONMEM® software are even more common. The objective of this study was to investigate the impact of using different parametric population modeling/analysis methods and distribution assumptions on population analysis results. METHODS: The dose duration-response data from 11 distinct skin blanching blinded pilot studies were fitted using FOCE (NONMEM®) and an EM algorithm (ADAPT5® (MLEM)). Three different Emax models were tested for each method. Population PD estimates and associated CV%, and the agreement between model predicted values and observed data were compared between the two methods. The impact of assuming different distributions of PD parameters was also investigated. RESULTS: The simple Emax model, as proposed in the FDA guidance, appeared to best characterize the data compared to more complex alternatives. The MLEM method in general appeared to provide better results than FOCE; lower population PD estimates with less inter-individual variability, and no variance shrinkage issues. The results also favored ln-normal versus normal distribution assumptions. CONCLUSIONS: The population ED50 estimates were influenced by both the type of population modeling methods and the distribution assumptions. We recommend updating the FDA guidance with more specific instructions related to the population approach to be used (EM-like versus FOCE-like methods) and to the normality assumptions that need to be set (ln-normal versus normal distribution).

Benchmarking of Human Dose Prediction for Inhaled Medicines from Preclinical In Vivo Data.

PURPOSE: A scientifically robust prediction of human dose is important in determining whether to progress a candidate drug into clinical development. A particular challenge for inhaled medicines is that unbound drug concentrations at the pharmacological target site cannot be easily measured or predicted. In the absence of such data, alternative empirical methods can be useful. This work is a post hoc analysis based on preclinical in vivo pharmacokinetic/pharmacodynamic (PK/PD) data with the aim to evaluate such approaches and provide guidance on clinically effective dose prediction for inhaled medicines. METHODS: Five empirically based methodologies were applied on a diverse set of marketed inhaled therapeutics (inhaled corticosteroids and bronchodilators). The approaches include scaling of dose based on body weight or body surface area and variants of PK/PD approaches aiming to predict the therapeutic dose based on having efficacious concentrations of drug in the lung over the dosing interval. RESULTS: The most robust predictions of dose were made by body weight adjustment (90% within 3-fold) and by a specific PK/PD approach aiming for an average predicted 75% effect level during the dosing interval (80% within 3-fold). Scaling of dose based on body surface area consistently under predicted the therapeutic dose. CONCLUSIONS: Preclinical in vivo data and empirical scaling to man can be used as a baseline method for clinical dose predictions of inhaled medicines. The development of more sophisticated translational models utilizing free drug concentration and target engagement data is a desirable build.

Bioequivalence Methodologies for Topical Drug Products: In Vitro and Ex Vivo Studies with a Corticosteroid and an Anti-Fungal Drug.

OBJECTIVE: To examine whether in vitro and ex vivo measurements of topical drug product performance correlate with in vivo outcomes, such that more efficient experimental approaches can be reliably and reproducibly used to establish (in)equivalence between formulations for skin application. MATERIALS AND METHODS: In vitro drug release through artificial membranes, and drug penetration into porcine skin ex vivo, were compared with published human in vivo studies. Two betamethasone valerate (BMV) formulations, and three marketed econazole nitrate (EN) creams were assessed. RESULTS: For BMV, the stratum corneum (SC) uptake of drug in 6 h closely matched data observed in vivo in humans, and distinguished between inequivalent formulations. SC uptake of EN from the 3 creams mirrored the in vivo equivalence in man (both clinically and via similar tape-stripping experiments). However, EN clearance from SC ex vivo did not parallel that in vivo, presumably due to the absence of a functioning microcirculation. In vitro release of BMV from the different formulations did not overlap with either ex vivo or in vivo tape-stripping data whereas, for EN, a good correlation was observed. No measurable permeation of either BMV or EN was detected in a 6-h in vitro skin penetration experiment. CONCLUSIONS: In vitro and ex vivo methods for topical bioequivalence determination can show correlation with in vivo outcomes. However, these surrogates have understandable limitations. A "one-size-fits-all" approach for topical bioequivalence evaluation may not always be successful, therefore, and the judicious use of complementary methods may prove a more effective and reliable strategy.

Predicting Pulmonary Pharmacokinetics from In Vitro Properties of Dry Powder Inhalers.

PURPOSE: The ability of two semi-mechanistic simulation approaches to predict the systemic pharmacokinetics (PK) of inhaled corticosteroids (ICSs) delivered via dry powder inhalers (DPIs) was assessed for mometasone furoate, budesonide and fluticasone propionate. METHODS: Both approaches derived the total lung doses and the central to peripheral lung deposition ratios from clinically relevant cascade impactor studies, but differed in the way the pulmonary absorption rate was derived. In approach 1, the rate of in vivo drug dissolution/absorption was predicted for the included ICSs from in vitro aerodynamic particle size distribution and in vitro drug solubility estimates measured in an in vivo predictive dissolution medium. Approach 2 derived a first order absorption rate from the mean dissolution time (MDT), determined for the test formulations in an in vitro Transwell® based dissolution system. RESULTS: Approach 1 suggested PK profiles which agreed well with the published pharmacokinetic profiles. Similarly, within approach 2, input parameters for the pulmonary absorption rate constant derived from dissolution rate experiments were able to reasonably predict the pharmacokinetic profiles published in literature. CONCLUSION: Approach 1 utilizes more complex strategies for predicting the dissolution/absorption process without providing a significant advantage over approach 2 with regard to accuracy of in vivo predictions.

Extra-fine particle inhaled corticosteroids, pharma-cokinetics and systemic activity in children with asthma.

During recent years, extra-fine particle inhaled corticosteroids with a median aerodynamic diameter ≤2 µm have been introduced in the treatment of asthma. The aim of this paper was to review pharmacokinetics and systemic activity of extra-fine particle hydroalkane pressurized metered dose inhaled (pMDI) ciclesonide and beclomethasone dipropionate in children. A literature review was performed. Systemic bioavailability of oral and pulmonary deposition of extra-fine ciclesonide and beclomethasone dipropionate was 52% and 82%, the half-life in serum 3.2 and 1.5 h and first-pass hepatic metabolism >99% and 60%, respectively. Secondary analyses of urine cortisol/creatinine excretion found no effects of ciclesonide pMDI between 40 and 320 µg/day or of beclomethasone dipropionate pMDI between 80 and 400 µg/day. Ciclesonide pMDI 40, 80 and 160 µg/day caused no effects on short-term lower leg growth rate as assessed by knemometry. Ciclesonide 320 µg/day was associated with a numerically short-term growth suppression equivalent to 30% which was similar to 25% and 36% suppression caused by beclomethasone dipropionate HFA and CFC 200 µg/day, respectively. Consistent with the differences in key pharmacokinetic features, beclomethasone dipropionate is associated with a systemic activity detected by knemometry at a lower dose than ciclesonide. Whether that correlates with a clinically important difference remains to be explored. Assessments of systemic activity of beclomethasone dipropionate <200 µg/day and of ciclesonide >180 µg/day as well as head-to-head comparisons are warranted. Preferably, such studies should apply the sensitive method of knemometry.

Pharmacokinetics of indacaterol and mometasone furoate delivered alone or in a free or fixed dose combination in healthy subjects.

PURPOSE: QMF149 is a fixed-dose combination of the long-acting ß2 agonist, indacaterol and the corticosteroid, mometasone furoate that is currently under development for treatment of patients with asthma and chronic obstructive pulmonary disease. We describe here a study designed to assess any pharmacokinetic (PK) and/or biopharmaceutical interaction between indacaterol and mometasone furoate when administered via the Breezhaler(®) device, either alone or in a free or fixed combination (QMF149) in healthy adult subjects. METHODS: In this randomized, open-label, four-way crossover study, subjects were randomized to receive indacaterol acetate 150 µg, mometasone furoate 320 µg, alone and as free combination of the individual components, or QMF149 (indacaterol acetate 150 µg/mometasone furoate 320 µg) once daily for 14 days in each period, followed by a 7-day washout between periods. PK profiles were characterized on Day 14 up to 168 h post-dose. RESULTS: Indacaterol AUC0-24h,ss and Cmax,ss after administration of QMF149 were 13% [ratio: 1.13; 90%CI: 1.09, 1.17] and 18% [ratio: 1.18; 90%CI: 1.12, 1.25] higher, respectively, than indacaterol monotherapy. Mometasone furoate AUC0-24h,ss and Cmax,ss after administration of QMF149 were 14% [ratio: 1.14; 90%CI: 1.09, 1.20] and 19% [ratio: 1.19; 90%CI: 1.13, 1.26], higher, respectively than mometasone furoate monotherapy. The majority (three of four comparisons between QMF149 and monotherapy) of the 90% confidence intervals of the between-treatment ratios for AUC0-24h,ss and Cmax,ss were within the 0.80 to 1.25 interval and therefore fulfilled bioequivalence criteria. The 90% confidence interval for Cmax,ss for MF for the QMF149 vs. monotherapy comparison was [1.13, 1.26]. Although no definitive data can be provided on the basis of the present study results, it is unlikely that the small observed differences in expsoure are clinically meaningful. Multiple inhaled doses of indacaterol and mometasone furoate, when administered alone, in free combination or as QMF149 were well tolerated. CONCLUSIONS: The QMF149 fixed dose combination treatment showed comparable systemic exposure to the free combination and monotherapy treatments in terms of AUC0-24h,ss and Cmax,ss for both indacaterol and mometasone furoate, indicating an absence of clinically relevant PK or biopharmaceutical interactions. These data support further development of QMF149 without dose adjustment.

The topical corticosteroid classification called into question: towards a new approach.

Vasoconstrictor assay described in 1962 was an interesting assessment of potency of topical corticosteroids at the beginning of these new therapies, however knowledge and technology have evolved and the classification should follow. A topical corticosteroids with a strong vasoconstrictor effect, as determined by vasoconstrictor assay, has not necessary a strong anti-inflammatory effect. Therefore a specific classification adapted to the therapeutic target is needed to be more efficient and thus reduce side effects and corticophobia.

Evaluation of the Transwell System for Characterization of Dissolution Behavior of Inhalation Drugs: Effects of Membrane and Surfactant.

Assessing the dissolution behavior of orally inhaled drug products (OIDs) has been proposed as an additional in vitro test for the characterization of innovator and generic drug development. A number of suggested dissolution methods (e.g., commercially available Transwell or Franz cell systems) have in common a membrane which provides the separation between the donor compartment, containing nondissolved drug particles, and an acceptor (sampling) compartment into which dissolved drug will diffuse. The goal of this study was to identify and overcome potential pitfalls associated with such dissolution systems using the inhaled corticosteroids (ICS), viz., budesonide, ciclesonide, and fluticasone propionate, as model compounds. A respirable fraction (generally stage 4 of a humidity, flow, and temperature controlled Andersen Cascade Impactor (ACI) or a Next Generation Impactor (NGI)) was collected for the tested MDIs. The dissolution behavior of these fractions was assessed employing the original and an adapted Transwell system using dissolution media which did or did not contain surfactant (0.5% sodium dodecyl sulfate). The rate with which the ICS transferred from the donor to the acceptor compartment was assessed by HPLC. Only a modified system that incorporated faster equilibrating membranes instead of the original 0.4 µm Transwell membrane resulted in dissolution and not diffusion being the rate-limiting step for the transfer of drug from the donor to the acceptor compartment. Experiments evaluating the nature of the dissolution media suggested that the presence of a surfactant (e.g., 0.5% SDS) is essential to obtain rank order of dissolution rates (e.g., for budesonide, fluticasone propionate, and ciclesonide) that is in agreement with absorption rates of these ICS obtained in studies of human pharmacokinetics. Using the optimized procedure, the in vitro dissolution behavior of budesonide, ciclesonide, and fluticasone propionate agreed approximately with descriptors of in vivo absorption. The optimized procedure, using membranes with increased permeability and surfactant containing dissolution medium, represents a good starting point to further evaluate in vitro/in vivo correlations.

Current perspectives on the contribution of inhaled corticosteroids to an increased risk for diabetes onset and progression in patients with chronic obstructive pulmonary disease.

Recent studies have suggested that inhaled corticosteroids (ICS) play a role in the development of hyperglycemia and type-2 diabetes in patients with chronic obstructive pulmonary disease (COPD). Nevertheless, this corticosteroid-associated adverse effect remains controversial. Moreover, the pharmacokinetic properties and patient characteristics that might contribute to an increased risk for diabetes upon ICS exposure have not been thoroughly investigated. In the present review, we critically discuss current evidence regarding the relationship between ICS therapy in COPD patients and an increased risk for the incidence and progression of type-2 diabetes. In addition, we address therapeutic conditions, clinical implications, and future perspectives related to this potentially important ICS-associated adverse effect in COPD patients.

Utility of serum ferritin and lactate dehydrogenase as surrogate markers for steroid therapy for Mycoplasma pneumoniae pneumonia.

INTRODUCTION: Patients with severe mycoplasma pneumonia having very high serum interleukin-18 levels may require systemic corticosteroid treatment. However, we know of no laboratory markers that have been identified to assess the precise severity of Mycoplasma pneumoniae pneumonia. Thus, we investigated the usefulness of four clinical laboratory tests as severity indicators and surrogate markers for initiation of steroid therapy in these patients. PATIENTS AND METHODS: For 22 Japanese children (including 3 patients who needed systemic corticosteroid therapy) diagnosed with Mycoplasma pneumoniae pneumonia, white blood cell counts and serum concentrations of interleukin-18, C-reactive protein, lactate dehydrogenase, and ferritin were determined in the acute and recovery phases. RESULTS: In total, 8 and 14 patients were classified as moderate and mild pneumonia, respectively, according to clinical manifestations. The serum interleukin-18 level in the acute phase of the pneumonia group was significantly higher than that of age-matched controls. Furthermore, serum interleukin-18, lactate dehydrogenase and ferritin levels in the acute phase increased in parallel with the severity of the pneumonia. The serum ferritin level was also higher in the acute phase than in the recovery phase. Positive correlations between the levels of serum interleukin-18, lactate dehydrogenase and ferritin were observed in the acute phase. CONCLUSIONS: Serum lactate dehydrogenase and ferritin levels may be useful as indicators of the severity of pediatric Mycoplasma pneumoniae pneumonia for initiation of corticosteroid therapy.