Metabolism of ciclesonide in the upper and lower airways: review of available data

Insights into Inhalation Drug Disposition: The Roles of Pulmonary Drug-Metabolizing Enzymes and Transporters

The past five decades have witnessed remarkable advancements in the field of inhaled medicines targeting the lungs for respiratory disease treatment. As a non-invasive drug delivery route, inhalation therapy offers numerous benefits to respiratory patients, including rapid and targeted exposure at specific sites, quick onset of action, bypassing first-pass metabolism, and beyond. Understanding the characteristics of pulmonary drug transporters and metabolizing enzymes is crucial for comprehending efficient drug exposure and clearance processes within the lungs. These processes are intricately linked to both local and systemic pharmacokinetics and pharmacodynamics of drugs. This review aims to provide a comprehensive overview of the literature on lung transporters and metabolizing enzymes while exploring their roles in exogenous and endogenous substance disposition. Additionally, we identify and discuss the principal challenges in this area of research, providing a foundation for future investigations aimed at optimizing inhaled drug administration. Moving forward, it is imperative that future research endeavors to focus on refining and validating in vitro and ex vivo models to more accurately mimic the human respiratory system. Such advancements will enhance our understanding of drug processing in different pathological states and facilitate the discovery of novel approaches for investigating lung-specific drug transporters and metabolizing enzymes. This deeper insight will be crucial in developing more effective and targeted therapies for respiratory diseases, ultimately leading to improved patient outcomes.

A randomized clinical trial on inhaled ciclesonide for managing acute asthma in the emergency room

BACKGROUND

Use of inhaled corticosteroids for managing acute asthma exacerbations has been tested since the 1990s.

OBJECTIVE

To compare high doses of inhaled ciclesonide with systemic hydrocortisone for managing acute asthma exacerbations in the emergency department.

DESIGN AND SETTING

Double-blind, randomized clinical trial in the public healthcare system of the city of São Paulo.

METHODS

Fifty-eight patients with moderate or severe asthma with peak flow < 50% of predicted were randomized into two groups. Over the course of four hours, one group received 1440 mcg of inhaled ciclesonide plus hydrocortisone-identical placebo (ciclesonide + placebo), while the other received 500 mg of intravenous hydrocortisone plus ciclesonide-identical placebo (hydrocortisone + placebo). Both groups received short-acting bronchodilators (fenoterol hydrobromide and ipratropium bromide). The research protocol included spirometry, clinical evaluation, vital signs and electrocardiogram monitoring. Data were obtained at 30 (baseline), 60, 90, 120, 180, and 240 minutes. We compared data from baseline to hour 4, between and within groups.

RESULTS

Overall, 31 patients received ciclesonide + placebo and 27 received hydrocortisone + placebo. Inhaled ciclesonide was as effective as intravenous hydrocortisone for improving clinical parameters (Borg-scored dyspnea, P = 0.95; sternocleidomastoid muscle use, P = 0.55; wheezing, P = 0.55; respiratory effort, P = 0.95); and spirometric parameters (forced vital capacity, P = 0.50; forced expiratory volume in the first second, P = 0.83; peak expiratory flow, P = 0.51).

CONCLUSIONS

Inhaled ciclesonide was not inferior to systemic hydrocortisone for managing acute asthma exacerbations, and it improved both clinical and spirometric parameters.

TRIAL REGISTRATION

RBR-6XWC26 - Registro Brasileiro de Ensaios Clínicos (http://www.ensaiosclinicos.gov.br/rg/RBR-6xwc26/).

LC-HRMS/MS study of the prodrug ciclesonide and its active metabolite desisobutyryl-ciclesonide in plasma after an inhalative administration to horses for doping control purposes

Ciclesonide (CIC) is the first inhaled highly potent corticosteroid that does not cause any cortisol suppression. It has been developed for the treatment of asthma in human and more recently in equine. CIC is the active compound of Aservo® EquiHaler® (Boehringer Ingelheim Vetmedica GmbH), the pre-filled inhaler generating a medicated mist based on Soft Mist™ technology. This prodrug is rapidly converted to desisobutyryl-ciclesonide (des-CIC), the main pharmacologically active compound. Due to its anti-inflammatory properties, CIC is prohibited for use in horse competitions. To set up an appropriate control, the determination of detection times and screening limits are required. Therefore, a highly sensitive analytical method based on supported liquid extraction (SLE) combined with liquid chromatography-high resolution tandem mass spectrometry (LC-HRMS/MS) was developed to detect CIC and its active metabolite des-CIC in plasma. The lower limit of detection of CIC and des-CIC was approximately 1 pg/ml in plasma. After a pilot study conducted on a single horse at the recommended dose (eight actuations twice daily corresponding to 5.5 mg/day for the first 5 days, followed by 12 actuations once daily corresponding to 4.1 mg/day in the last 5 days), the same protocol was applied in the main study using six horses. In all horses, CIC and des-CIC levels were less than 5 and 10 pg/ml, respectively, at 36 h after the end of the administration. The outcome of this risk assessment study should be useful to draw any recommendations for horse competitions.

Ciclesonide activates glucocorticoid signaling in neonatal rat lung but does not trigger adverse effects in the cortex and cerebellum

Synthetic glucocorticoids (sGCs) such as dexamethasone (DEX), while used to mitigate inflammation and disease progression in premature infants with severe bronchopulmonary dysplasia (BPD), are also associated with significant adverse neurologic effects such as reductions in myelination and abnormalities in neuroanatomical development. Ciclesonide (CIC) is a sGC prodrug approved for asthma treatment that exhibits limited systemic side effects. Carboxylesterases enriched in the lower airways convert CIC to the glucocorticoid receptor (GR) agonist des-CIC. We therefore examined whether CIC would likewise activate GR in neonatal lung but have limited adverse extra-pulmonary effects, particularly in the developing brain. Neonatal rats were administered subcutaneous injections of CIC, DEX or vehicle from postnatal days 1-5 (PND1-PND5). Systemic effects linked to DEX exposure, including reduced body and brain weight, were not observed in CIC treated neonates. Furthermore, CIC did not trigger the long-lasting reduction in myelin basic protein expression in the cerebral cortex nor cerebellar size caused by neonatal DEX exposure. Conversely, DEX and CIC were both effective at inducing the expression of select GR target genes in neonatal lung, including those implicated in lung-protective and anti-inflammatory effects. Thus, CIC is a promising, novel candidate drug to treat or prevent BPD in neonates given its activation of GR in neonatal lung and limited adverse neurodevelopmental effects. Furthermore, since sGCs such as DEX administered to pregnant women in pre-term labor can adversely affect fetal brain development, the neurological-sparing properties of CIC, make it an attractive alternative for DEX to treat pregnant women severely ill with respiratory illness, such as with asthma exacerbations or COVID-19 infections.

An Ultrasensitive LC-APPI-MS/MS Method for Simultaneous Determination of Ciclesonide and Active Metabolite Desisobutyryl-Ciclesonide in Human Serum and Its Application to a Clinical Study

BACKGROUND

The development of more efficient drug delivery devices for ciclesonide inhalation products requires an ultrasensitive bioanalytical method to measure systematic exposure of ciclesonide (CIC) and its active metabolite desisobutyryl-ciclesonide (des-CIC) in humans.

METHOD

Serum sample was extracted with 1-chlorobutane. A reversed-phase liquid chromatography coupled with atmospheric pressure photoionization-tandem mass spectrometry (LC-APPI-MS/MS) method was used for quantification of 1-500 pg/mL for both analytes in a 0.500-mL serum. The analysis time was 4.7 min/injection. CIC-d11 and des-CIC-d11 were used as the internal standards.

RESULTS

Calibration curves showed good linearity (r2 > 0.99) for both analytes. This novel method was precise and accurate with interassay precision and accuracy of all within 9.6% CV and ± 4.0% bias for regular QC samples. Extraction recovery was approximately 85% for both analytes. Serum samples are stable for 3 freeze-thaw cycles, 24 h at bench top, and up to 706 days at both -20 °C and -70 °C. This method was successfully used to support a pharmacokinetic (PK) comparison between the inhalation suspensions and an inhalation aerosol of ciclesonide in healthy participants. The method robustness was also supported by the good incurred sample reanalysis reproducibility.

CONCLUSION

APPI, a highly selective and sensitive ionization source, made possible for quantifying CIC and des-CIC with a lower limit of quantification (LLOQ) of 1 pg/mL in human serum by LC-MS/MS. A 10-fold sensitivity improvement from the most sensitive reported method (LLOQ, 10 pg/mL) is essential to fully characterize the PK profiles of CIC and des-CIC in support of the clinical development of the ciclesonide-related medications for patients.

Visualizing the spatial localization of ciclesonide and its metabolites in rat lungs after inhalation of 1-μm aerosol of ciclesonide by desorption electrospray ionization-time of flight mass spectrometry imaging

Inhaled ciclesonide (CIC), a corticosteroid used to treat asthma that is also being investigated for the treatment of corona virus disease 2019, hydrolyzes to desisobutyryl-ciclesonide (des-CIC) followed by reversible esterification when exposed to fatty acids in lungs. While previous studies have described the distribution and metabolism of the compounds after inhalation, spatial localization in the lungs remains unclear. We visualized two-dimensional spatial localization of CIC and its metabolites in rat lungs after administration of a single dose of a CIC aerosol (with the mass median aerodynamic diameter of 0.918-1.168 μm) using desorption electrospray ionization-time of flight mass spectrometry imaging (DESI-MSI). In the analysis, CIC, des-CIC, and des-CIC-oleate were imaged in frozen lung sections at high spatial and mass resolutions in negative-ion mode. MSI revealed the coexistence of CIC, des-CIC, and des-CIC-oleate on the airway epithelium, and the distribution of des-CIC and des-CIC-oleate in peripheral lung regions. In addition, a part of CIC independently localized on the airway epithelium. These results suggest that distribution of CIC and its metabolites in lungs is related to both the intended delivery of aerosols to pulmonary alveoli and peripheral regions, and the potential deposition of CIC particles on the airway epithelium.

Presence and inter-individual variability of carboxylesterases (CES1 and CES2) in human lung

Lungs are pharmacologically active organs and the pulmonary drug metabolism is of interest for inhaled drugs design. Carboxylesterases (CESs) are enzymes catalyzing the hydrolysis of many structurally different ester, amide and carbamate chemicals, including prodrugs. For the first time, the presence, kinetics, inhibition and inter-individual variations of the major liver CES isozymes (CES1 and CES2) were investigated in cytosol and microsomes of human lungs from 20 individuals using 4-nitrophenyl acetate (pNPA), 4-methylumbelliferyl acetate (4-MUA), and fluorescein diacetate (FD) as substrates the rates of hydrolysis (V_max) for pNPA and 4-MUA, unlike FD, were double in microsomes than in cytosol. In these cellular fractions, the V_max of pNPA, as CES1 marker, were much greater (30-50-fold) than those of FD, as a specific CES2 marker. Conversely, the K_m values were comparable suggesting the involvement of the same enzymes. Inhibition studies revealed that the FD hydrolysis was inhibited by bis-p-nitrophenylphosphate, phenylmethanesulfonyl fluoride, and loperamide (specific for CES2), whereas the pNPA and 4-MUA hydrolysis inhibition was limited. Inhibitors selective for other esterases missed having any effect on above-mentioned activities. In cytosol and microsomes of 20 lung samples, inter-individual variations were found for the hydrolysis of pNPA (2.5-5-fold), FD or 4-MUA (8-15-fold). Similar variations were also observed in CES1 and CES2 gene expression, although determined in a small number (n = 9) of lung samples. The identification of CES1 and CES2 and their variability in human lungs are important for drug metabolism and design of prodrugs which need to be activated in this organ.

Novel, Alternative, and Controversial Therapies of Rhinitis

Rhinitis is a multifactorial disease characterized by sneezing, rhinorrhea, postnasal drip, and nasal congestion. This condition affects 10% to 40% of the population and is responsible for billions of spent health care dollars and impairment in quality of life for those affected. Currently available medical and vaccine therapies are effective for a large segment of this population; however, a subset of patients still has difficult-to-control rhinitis. This article reviews the current progress being made in novel drug and vaccine development and delves into alternative medical, surgical, and homeopathic strategies that may be promising adjunctive treatments for the difficult-to-treat rhinitis patient.

Nasal deposition of ciclesonide nasal aerosol and mometasone aqueous nasal spray in allergic rhinitis patients

BACKGROUND

Sensory attributes of intranasal corticosteroids, such as rundown to the back of the throat, may influence patient treatment preferences. This study compares the nasal deposition and nasal retention of a radiolabeled solution of ciclesonide nasal aerosol (CIC-hydrofluoroalkane [HFA]) with a radiolabeled suspension of mometasone furoate monohydrate aqueous nasal spray (MFNS) in subjects with either perennial allergic rhinitis (AR) or seasonal AR.

METHODS

In this open-label, single-dose, randomized, crossover scintigraphy study, 14 subjects with symptomatic AR received a single dose of radiolabeled 74-μg CIC-HFA (37 μg/spray, 1 spray/each nostril) via a nasal metered-dose inhaler or a single dose of radiolabeled 200-μg MFNS (50 μg/spray, 2 sprays/each nostril), with a minimum 5-day washout period between treatments. Initial deposition (2 minutes postdose) of radiolabeled CIC-HFA and MFNS in the nasal cavity, nasopharynx, and on nasal wipes, and retention of radioactivity in the nasal cavity and nasal run-out on nasal wipes at 2, 4, 6, 8, and 10 minutes postdose were quantified with scintigraphy.

RESULTS

At 2 and 10 minutes postdose, deposition of radiolabeled CIC-HFA was significantly higher in the nasal cavity versus radiolabeled MFNS (99.42% versus 86.50% at 2 minutes, p = 0.0046; and 81.10% versus 54.31% at 10 minutes, p < 0.0001, respectively; p values unadjusted for multiplicity). Deposition of radioactivity on nasal wipes was significantly higher with MFNS versus CIC-HFA at all five time points, and posterior losses of radiolabeled formulation were significantly higher with MFNS at 6, 8, and 10 minutes postdose.

CONCLUSION

In this scintigraphic study, significantly higher nasal deposition and retention of radiolabeled aerosol CIC-HFA were observed versus radiolabeled aqueous MFNS in subjects with AR.

From inhaler to lung: clinical implications of the formulations of ciclesonide and other inhaled corticosteroids

Asthma continues to be a global health problem and currently available treatments such as corticosteroids can cause unwanted side effects. Inhaled corticosteroids (ICS) are recommended as first-line therapy for reducing airway inflammation and have a distinct advantage over oral preparations as they provide a direct route of delivery to the lungs. However, local deposition of ICS in the oropharynx can lead to oral candidiasis, dysphonia, and pharyngitis. The pharmaceutical quality is a primary concern of any ICS asthma treatment, with a higher quality product resulting in improved efficacy and safety profiles. The particle size distribution and the spray force velocity of an ICS may directly influence lung deposition, and the spray duration of a device is another important factor when coordinating inhalation. Recent advances in ICS device and formulation technology have resulted in significant improvements in the efficacy of available asthma treatments. In particular, hydrofluoroalkane (HFA) solution technology and the development of smaller particle sizes have resulted in the production of new ICS formulations that have the ability to directly target drug delivery to the site of airway inflammation. Both the ICS formulation and the pressurized metered-dose inhaler device used to administer ciclesonide (CIC) HFA have been developed to treat the underlying chronic inflammation associated with asthma. CIC is administered as a prodrug which is activated in the lungs, leading to minimal oropharyngeal deposition. The small particle size of CIC results in the delivery of a high fraction of respirable particles to the small airways of the lungs, resulting in high lung deposition and continual dose consistency. This review summarizes how CIC administered as an HFA formulation is an effective treatment for asthma.

Repeated-dose pharmacokinetics of inhaled ciclesonide (CIC-HFA) in Japanese children with bronchial asthma: a phase I study

BACKGROUND

Ciclesonide (CIC) is a highly safe, inhaled corticosteroid (ICS) that is converted into a pharmacologically active metabolite (des-isobutyryl-ciclesonide); this metabolite, in turn, exerts a local anti-inflammatory effect on lung tissue. The present study was undertaken to analyze the pharmacokinetics of des-isobutyryl-ciclesonide in the serum of Japanese children with bronchial asthma treated by repeated doses of CIC and to compare the data thus obtained with those obtained for Caucasian children with bronchial asthma.

METHODS

Eight Japanese children with bronchial asthma were treated for 7 days with CIC-hydrofluoroalkalane (CIC-HFA) 200 μg/day administered by a metered-dose inhaler. The study was designed to assess the pharmacokinetics after 7-day repeated administration by which the steady state can be achieved, based on the results of an earlier study involving healthy Japanese adult males who received 7-day repeated administration of CIC-HFA. Blood was sampled at multiple time points on Day 7 of treatment for measurement of the serum des-isobutyryl-ciclesonide level.

RESULTS

The pharmacokinetic parameters (AUC from time zero to last observed concentration [AUC(t)], AUC over the dosage interval τ at steady state [AUC(ss)], maximum concentration [C(max)], and terminal elimination half-life [T(1/2)]) and the temporal changes in the serum levels of des-isobutyryl-ciclesonide after repeated administration of CIC-HFA (200 μg/day) in Japanese children with bronchial asthma differed only slightly from those in Caucasian children with bronchial asthma. No serious adverse events were noted during the study period. Additionally, no abnormalities were detected in the serum cortisol level, other laboratory parameters, or vital signs.

CONCLUSIONS

Our results suggest that there is little difference in the pharmacokinetics of des-isobutyryl-ciclesonide up on repeated administration of CIC-HFA between Japanese and Caucasian children with bronchial asthma. And our study suggests that CIC-HFA (200 μg/day, once daily) can be administered safely for 7 days, without raising any safety concerns.

Determination of lung deposition following inhalation of ciclesonide using different bioanalytical procedures

Ciclesonide (Alvesco(®)) is an inhaled corticosteroid administered as a solution via a metered-dose inhaler, using hydrofluoroalkane HFA-134a as a propellant. Ciclesonide is inhaled as a prodrug, which is activated by pulmonary esterases to the pharmacologically active metabolite desisobutyryl-ciclesonide (des-CIC). Lung deposition is an important factor that contributes to the desired therapeutic effect of inhaled corticosteroid. More than 50% of the inhaled dose is deposited in the lung as demonstrated by scintigraphical methods after inhalation of ciclesonide. The swallowed drug does not contribute to the systemic circulation because of the low oral systemic bioavailability, which is below 1% for ciclesonide and des-CIC. Due to the negligible oral bioavailability the pharmacokinetic parameters following inhalation are a surrogate for lung deposition. The pulmonary bioavailability was more than 60% as assessed for des-CIC in pharmacokinetic studies using HPLC-MS/MS detection as bioanalytical method. Pharmacokinetics in asthmatic patients and healthy subjects are similar.

Intranasal delivery--modification of drug metabolism and brain disposition

Intranasal route continues to be one of the main focuses of drug delivery research. Although it is generally perceived that the nasal route could avoid the first-pass metabolism in liver and gastrointestinal tract, the role of metabolic conversions in systemic and brain-targeted deliveries of the parent compounds and their metabolites should not be underestimated. In this commentary, metabolite formations after intranasal and other routes of administration are compared. Also, the disposition of metabolites in plasma and brain after nasal administrations of parent drugs, prodrugs and preformed metabolites will be discussed. The importance and implications of metabolism for future nasal drug development are highlighted.

Clinical pharmacokinetic and pharmacodynamic profile of inhaled ciclesonide

Asthma is a chronic inflammatory disease of the airways, and inhaled corticosteroids (ICSs) are recommended as first-line therapy for persistent asthma of all severities. Ciclesonide is a novel ICS, which is administered as an aerosol solution in a metered-dose inhaler, using hydrofluoroalkane-134a as a propellant. Because of the high respirable particle fraction, high pulmonary deposition is obtained in patients, which constitutes the basis of effective therapeutic action. The parent compound, ciclesonide, is pharmacologically inactive and is activated in the target organ, the lung, to form its only pharmacologically active metabolite, desisobutyryl-ciclesonide (des-CIC). Low oral deposition combined with minimal formation of des-CIC in the oropharynx may minimize the typical oropharyngeal adverse events associated with ICSs. Low oral bioavailability, rapid clearance and high protein binding reduce pharmacologically relevant systemic exposure. The unique pharmacokinetic and pharmacodynamic profile of ciclesonide offers a rationale that supports the favourable risk-benefit profile observed in clinical trials in patients with persistent asthma.