Microdialysis as a tool to determine the skin concentration of mometason furoate in rats

The objective of this study was to investigate the feasibility of microdialysis as a tool to determine the skin concentration of mometason furoate (MF), a lipophilic and highly protein-bound compound. The relative recovery (RR) of mometasone furoate was determined by an in vitro no-net-flux method using three different perfusates (40% PEG400, 5% fat emulsion, and 20% fat emulsion) and four flow rates (0.5, 1, 2, and 4 μL x min(-1)). With the increasing of flow rate, the relative recovery was decreased from 48.8% to 3.1%. The in vitro recovery was increased to 23.71%, 42.76% and 56.21% when 40% PEG400, 5% fat emulsion or 20% fat emulsion was used as microdialysis perfusates, respectively. Fat emulsion (5%) was chosen as the perfusate to evaluate the in vivo recovery by a retrodialysis method, in which mometasone furoate concentration in different tissues was determined. The result showed that concentrations of mometasone furoate in the dermis was greater than that in the subcutaneous or muscle tissue. It was concluded that a recovery enhancer could be used in microdialysis technique, especially for determining skin concentrations of lipophilic and high protein-bounds.

Use of mometasone furoate administered via a dry powder inhaler in the treatment of asthma

BACKGROUND

Inhaled corticosteroids (ICSs) are effective controller medications that treat the chronic inflammation of asthma. The goal of asthma treatment is to improve lung function, symptoms, and the ability to perform daily activities, while decreasing the risk of exacerbations. Mometasone furoate delivered via a dry powder inhaler (MF-DPI) is indicated for once-daily maintenance treatment of asthma in patients as young as 4 years old.

OBJECTIVE

To review the quality of evidence for the clinical efficacy and safety of MF-DPI in both adults and children in the context of grading systems for guideline recommendations. Publications were identified by searching PubMed (MEDLINE) for 'mometasone furoate AND dry powder inhaler AND asthma' in any field with search limits for publications from 1 January 1995 to 1 August 2008.

FINDINGS

MF-DPI has been evaluated in 21 randomized, double-blind, active- or placebo-controlled trials in adults with asthma. Clinical trials investigating the efficacy in patients previously treated with only short-acting beta(2)-agonists, other ICSs, or oral corticosteroids revealed that MF-DPI is efficacious in these populations. The results of a pooled analysis of ten trials and individual results of three long-term safety trials indicate that MF-DPI is well-tolerated with minimal adverse events. Six clinical trials of MF-DPI have been completed in children. Studies of pediatric patients treated with approved doses of MF-DPI indicate that children previously maintained on twice-daily treatment of other ICSs showed improvements in lung function, health-related quality of life, and rescue medication use. In addition, there is no effect on growth velocity or the hypothalamic-pituitary-adrenal axis. In both adults and children, once-daily dosing of MF-DPI has been demonstrated to be as efficacious as twice-daily dosing.

CONCLUSION

The findings of this single-database review are that once-daily MF-DPI is efficacious and safe in both adults and children with asthma.

Molecular and clinical pharmacology of intranasal corticosteroids: clinical and therapeutic implications

Intranasal corticosteroids (INSs) are effective treatments for allergic rhinitis, rhinosinusitis, and nasal polyposis. In recent years, increased understanding of corticosteroid and glucocorticoid receptor pharmacology has enabled the development of molecules designed specifically to achieve potent, localized activity with minimal risk of systemic exposure. Pharmacologic potency studies using affinity and other assessments have produced similar rank orders of potency, with the most potent being mometasone furoate, fluticasone propionate, and its modification, fluticasone furoate. The furoate and propionate ester side chains render these agents highly lipophilic, which may facilitate their absorption through nasal mucosa and uptake across phospholipid cell membranes. These compounds demonstrate negligible systemic absorption. Systemic absorption rates are higher among the older corticosteroids (flunisolide, beclomethasone dipropionate, triamcinolone acetonide, and budesonide), which have bioavailabilities in the range of 34-49%. Studies, including 1-year studies with mometasone furoate, fluticasone propionate, and budesonide that evaluated potential systemic effects of INSs in children have generally found no adverse effects on hypothalamic-pituitary-adrenal axis function or growth. Clinical data suggest no significant differences in efficacy between the INSs. Theoretically, newer agents with lower systemic availability may be preferable, and may come closer to the pharmacokinetic/pharmacologic criteria for the ideal therapeutic choice.

Intracellular delivery of nanoparticles of an antiasthmatic drug

The aim of the investigation was to prepare and characterize wheat germ agglutinin(WGA)-conjugated poly(D: ,L-lactic-co-glycolic) acid nanoparticles encapsulating mometasone furoate (MF) as a model drug and assess changes in its fate in terms of cellular interactions. MF loaded nanoparticles were prepared using emulsion-solvent evaporation technique. WGA-conjugation was done by carbodiimide coupling method. The nanoparticles were characterized for size, zeta potential, entrapment efficiency and in-vitro drug release. The intracellular uptake of nanoparticles, drug cellular levels, and anti-proliferative activity studies of wheat germ agglutinin-conjugated and unconjugated nanoparticles were assessed on alveolar epithelial (A549) cells to establish cellular interactions. Prepared nanoparticles were spherical with 10-15 microg/mg of WGA conjugated on nanoparticles. The size of nanoparticles increased after conjugation and drug entrapment and zeta potential reduced from 78 +/- 5.5% to 60 +/- 2.5% and -15.3 +/- 1.9 to -2.59 +/- 2.1 mV respectively after conjugation. From the cellular drug concentration-time plot, AUC was found to be 0.4745, 0.6791 and 1.24 for MF, MF-nanoparticles and wheat germ agglutinin-MF-nanoparticles respectively. The in-vitro antiproliferative activity was improved and prolonged significantly after wheat germ agglutinin-conjugation. The results conclusively demonstrate improved availability and efficacy of antiasthmatic drug in alveolar epithelial cell lines. Hence, a drug once formulated as mucoadhesive nanoparticles and incorporated in dry powder inhaler formulation may be used for targeting any segment of lungs for more improved therapeutic response in other lung disorders as well.

Pharmacokinetic/pharmacodynamic evaluation of urinary cortisol suppression after inhalation of fluticasone propionate and mometasone furoate

AIM

Fluticasone propionate (FP) and mometasone furoate (MF) are inhaled corticosteroids that possess a high ratio of topical to systemic activity. The systemic bioavailability of MF has been claimed to be minimal (1%). FP has been shown to exhibit the same degree of systemic effects, but its systemic availability is between 13 and 17%. We hypothesize that FP and MF have comparable systemic availabilities that can explain their potential to cause systemic effects.

METHODS

Steady-state FP and MF trough plasma samples were determined from a clinical study by Fardon et al. in patients with persistent asthma (forced expiratory volume in 1 s = 91%). The percent plasma protein binding of FP and MF was measured using ultracentrifugation. Free FP plasma concentrations were normalized for their differences in receptor binding affinity compared with MF and linked to overnight urinary cortisol/creatinine with an inhibitory E(max).

RESULTS

A plot of steady-state FP and MF total trough plasma concentrations vs. dose showed that both drugs exhibit dose linearity. MF has comparable bioavailability to FP based on the steady-state concentrations observed for the different doses. The free plasma concentration producing 50% of urinary cortisol suppression (IC(50)) for MF was not statistically different from the free, normalized IC(50) for FP.

CONCLUSION

FP and MF have similar pulmonary deposition and the same potential to cause systemic side-effects due to their similar IC(50) values. The observed urinary cortisol suppression of FP and MF is in agreement with their systemic availability, their differences in plasma protein binding and receptor binding affinity.

Pharmacokinetics and metabolism of anecortave acetate in animals and humans

The ocular delivery of anecortave acetate was tested in preclinical and clinical pharmacokinetic and metabolism studies. Results of initial studies led to the design of a new cannula that could effectively deliver anecortave acetate as a posterior juxtascleral depot, providing adequate retinal and choroidal drug concentrations for up to 6 months after a single administration. A counter-pressure device was designed to prevent drug reflux during and immediately after posterior juxtascleral depot administration. Pharmacokinetic studies support the effectiveness of these devices. Anecortave acetate is rapidly hydrolyzed by esterases to pharmacologically active anecortave desacetate, and is further reductively metabolized to one major and several minor products that circulate as glucuronide conjugates. Low levels of these anecortave acetate metabolites were detectable for only approximately 2 weeks in the plasma after a 15-mg posterior juxtascleral depot administration to age-related macular degeneration patients. Studies show that posterior juxtascleral depot administration of anecortave acetate is an effective, minimally invasive method of delivering this drug to the choroid and retina.

POSTERIOR JUXTASCLERAL INJECTION OF ANECORTAVE ACETATE

PURPOSE

To confirm juxtascleral delivery of anecortave acetate in rabbit eyes by ocular imaging techniques and to determine drug localization and distribution as a function of time after injection.

METHODS

Four female New Zealand white rabbits (weight, 2.5-3.0 kg) received a single juxtascleral posterior sub-Tenon capsule injection of 0.5 mL or 1 mL of 30 mg/mL anecortave acetate. Rabbit eyes were imaged with ultrasonography and magnetic resonance imaging (MRI) before injection, immediately after injection, and at 2 hours, 1 week, and 4 weeks after injection. Rabbit eyes were also imaged with b-mode ultrasonography during the juxtascleral injections.

RESULTS

Ultrasonography and MRI demonstrated that juxtascleral posterior sub-Tenon capsule injection of anecortave acetate effectively delivered the drug in direct apposition to the posterior pole of the rabbit eye. The drug remained in the juxtascleral site for at least 5 weeks. The drug was visualized clearly by MRI immediately after injection, decreasing in intensity thereafter. Cannula insertion and the drug delivery process were clearly visualized by real-time ultrasound analysis. Immediately after drug injection, ultrasonography indirectly localized anecortave acetate localization as an echolucent zone posterior to the scleral surface. At the later time points, however, the juxtascleral location of the drug was verified with ultrasonography as a relatively echogenic focus in the same location.

CONCLUSIONS

Juxtascleral administration of anecortave acetate via a posterior sub-Tenon capsule approach effectively delivered the drug to the desired position in direct apposition to the globe posteriorly. MRI and ultrasonography both demonstrated that anecortave acetate remained localized to this location for at least 5 weeks after initial injection.

METABOLISM OF MOMETASONE FUROATE AND BIOLOGICAL ACTIVITY OF THE METABOLITES

To better evaluate the pharmacokinetic and pharmacodynamic properties of the new inhaled glucocorticoid mometasone furoate (MF), the metabolism of MF was evaluated in rat and human tissues and in rat after i.v. administration. Metabolic studies with 3H-MF in human and rat plasma and S9 fractions of human and rat lung showed relatively high stability and a degradation pattern similar to that seen in buffer systems. MF was efficiently metabolized into at least five metabolites in S9 fractions of both rat and human liver. There were, however, quantitative differences in the metabolites between the two species. The apparent half-life of MF in the S9 fraction of human liver was found to be 3 times greater compared with that in rat. MET1, the most polar metabolite, was the major metabolite in rat liver fractions, whereas both MET1 and MET2 were formed to an equal extent in human liver. Metabolism and distribution studies in rats after intravenous and intratracheal administration of [1,2-(3)H]MF revealed that most of the radioactivity (approximately 90%) was present in the stomach, intestines, and intestinal contents, suggesting biliary excretion of MF and its metabolites. Radiochromatography showed that most radioactivity was associated with MET1, MET2, and MET 3. Fractionation of the high-performance liquid chromatography eluate (MET1-5) revealed that only MF [relative binding affinity (RBA) 2900] and MET2 (RBA 700) had appreciable glucocorticoid receptor binding affinity. These results suggest that MF undergoes distinct extrahepatic metabolism but generates active metabolites that might be in part responsible for the systemic side effects of MF.

Comparative potency of formulations of mometasone furoate in terms of inhibition of ′PIRHR′ in the forearm skin of normal human subjects measured with laser doppler velocimetry

BACKGROUND AND AIMS

Topical glucocorticoid formulations are widely used for effective treatment and control of a variety of dermatoses. Mometasone furoate is a newer corticoid that has high potency but low systemic toxicity. Pharmaceutical factors are known to significantly influence potency and systemic absorption of topically applied glucocorticoids. We studied the potency of "Elocon", a topical formulation of mometasone furoate, compared with two other branded formulations of the same corticoid.

METHODS

Corticoid potency was measured by employing a pharmacodynamic parameter of an inhibitory effect of the corticoid on post-ischemic-reactive-hyperemic-response (PIRHR) in human forearm skin under occlusive dressing. The PIRHR was expressed in terms of % increase in the skin blood flow (SBF) as measured with laser doppler velocimetry (LDV).

RESULTS

All three active branded formulations of mometasone furoate produced significant inhibition of PIRHR. The AUC(0-2 min) of PIRHR was ( Mean +/- SEM ), Control = 213.52 +/- 11.80, Placebo = 209.77 +/- 19.31, Formulation A = 119.83 +/- 13.71, Formulation C = 53.67 +/- 4.85 and Formulation D = 111.46 +/- 22.87. Formulation "C" exhibited significantly higher topical anti-inflammatory potency than formulations "A" or "D".

CONCLUSIONS

Thus, branded formulations of the same glucocorticoid, mometasone furoate significantly differed in their topical anti-inflammatory potency. "Elocon" was significantly more potent than the two other branded formulations studied.

Adrenal Suppression with Dry Powder Formulations of Fluticasone Propionate and Mometasone Furoate

Mometasone furoate (MF) and fluticasone propionate (FP) are high potency inhaled corticosteroids. The systemic bioavailability of MF is claimed to be negligible, leading to a minimal potential for systemic adverse effects. We assessed the overnight urinary cortisol/creatinine as the primary outcome of adrenal suppression in 21 patients with persistent asthma (mean FEV1 = 91%). Patients were randomized in a crossover fashion to receive 2 weekly consecutive doubling incremental doses of either FP Accuhaler (500, 1,000, and 2,000 microg/day) or MF Twisthaler (400, 800, and 1,600 microg/day). For the 21 per protocol completed patients, there was significant suppression of overnight urinary cortisol/creatinine with high and medium doses of both drugs-as geometric mean fold suppression (95% confidence interval) from baseline: FP 2,000 microg, 1.85 (1.21-2.82, p = 0.002); FP 1,000 microg, 1.45 (1.07-1.96, p = 0.02); MF 1,600 microg, 1.92 (1.26-2.93, p = 0.001); and MF 800 microg, 1.39 (1.04-1.88, p = 0.02). For secondary outcomes of 8:00 A.M. plasma cortisol, serum osteocalcin, and early morning urinary cortisol/creatinine, there was significant suppression with MF and FP at the highest dose. Our data refute the assertion that MF has negligible systemic bioavailability and a lower potential for systemic adverse effects compared with FP.

Aspects of pharmacodynamics and biotransformation of the glucocorticoid resocortol butyrate

Aspects of the biotransformation and pharmacodynamics of the novel glucocorticoid resocortol butyrate (RCB) and its metabolites were assessed in vitro and in vivo in comparison with selected reference compounds. The main route of biotransformation of ((3)H)-RCB in the skin and the liver was 5alpha-reduction of the A-ring followed by reduction of the 3-carbonyl group. In the liver, metabolism was much more rapid than in the skin and 5beta-reduction also occurred. RCB had a relative binding affinity for the glucocorticoid receptor similar to that of triamcinolone acetonide, about 1.5 times that of dexamethasone, three times that of betamethasone valerate (BMV) and 10-14 times that of cortisol. The metabolites of RCB displayed only low to very low affinities for the receptor. The suppression of the hypothalamic-pituitary-adrenal axis was investigated in placebo- and positive-controlled studies in dogs by measurement of basal and corticotrophin-releasing hormone (CRH) stimulated plasma cortisol concentrations. The AUC of the plasma cortisol vs. time curve following CRH stimulation, a measure of adrenal suppression, was reduced significantly after topical application of BMV compared with the pretreatment values. The AUC in the RCB group was not reduced significantly. Adrenocorticotrophic hormone concentrations were not affected. Oral administration of RCB did not suppress adrenocortical function, whereas BMV induced almost complete suppression of basal and CRH-induced cortisol concentrations. The pharmacodynamics of RCB makes it a relatively safe glucocorticosteroid for topical application.

Characterization of degradation products of mometasone furoate

Mometasone furoate (MF) is a synthetic glucocorticoid with anti-inflammatory activity, which is used for the treatment of topical skin disorders, allergic rhinitis and treatment of mild to moderate persistent asthma. The focus of this study is to examine the stability of MF in simulated lung fluid (SLF) and to clearly identify the structure of the degradation products of MF by MS and NMR analysis. Mometasone furoate degradation leads to the formation of two products, D1 and D2 with significant pH dependence. The half-lives for the conversion of MF to D1 and subsequent conversion of D1 to D2 at 37 degrees C in SLF were 1.3 and 4.8 h respectively. LC-MS and NMR analysis confirmed that D1 is 9,11-epoxide mometasone furoate while D2 represents a new chemical structure that shows cyclization within the C17-C21 region. The biological activity of these degradation products was assessed in rat lung glucocorticoid receptor binding studies. D1 showed 4 fold greater receptor affinity to glucocorticoid receptors compared to dexamethasone. However, the receptor affinity for D2 was a log order lower than that for dexamethasone. The instability of MF in SLF resulted in two degradation products, one of the degradation products showing glucocorticoid receptor activity, the other representing a new cyclized structure whose pharmacological properties have not been described. The biological significance of these degradation products is unknown.

Bioavailability of fluticasone propionate and mometasone furoate aqueous nasal sprays

OBJECTIVES

To compare the systemic exposure for intranasal mometasone furoate (MF) and fluticasone propionate (FP) aqueous nasal sprays (ANS) in terms of serum and urinary cortisol parameters and plasma pharmacokinetics.

METHODS

Twelve healthy subjects completed this three-way, cross-over study. They received FPANS (50 microg/spray), MFANS (50 microg/spray) or placebo ANS, eight sprays per nostril every 8 h for 4 days. Cortisol measurements were made at baseline and day 4. FP and MF plasma concentrations were also measured on day 4.

RESULTS

MFANS produced similar mean plasma AUC (123 pmol/l h) to FPANS (112 pmol/l h). Despite the use of high doses, necessary to generate adequate pharmacokinetic data, only minor reductions in cortisol parameters were found, with no difference between FPANS and MFANS.

CONCLUSIONS

FP and MF have similar and very low systemic bioavailability when administered intranasally using a high-dose regimen. It is therefore unlikely that therapeutic doses of intranasal FP or MF will produce dissimilar or significant degrees of systemic exposure or systemic effects.

Dissolution of Anecortave Acetate in a Cylindrical Flow Cell: Re‐Evaluation of Convective Diffusion/Drug Dissolution for Sparingly Soluble Drugs

Steady-state drug release rates were measured from a model cylindrical implant, comprised mainly of the sparingly soluble drug anecortave acetate, suspended as an obstacle in a cylindrical flow cell. Dissolution medium was delivered at a steady, slow flow rate (0.05-0.7 mLs/min) using an HPLC pump, and samples from the outflow were analyzed by direct injection onto an HPLC column. Release rates were determined as a function of flow rate for three different implant orientations--vertical, elevated to the center of the dissolution cell; horizontal, elevated; and horizontal, resting directly upon the flat porous inlet frit. Release rates were ranked as follows: horizontal, floor >> horizontal, elevated>vertical, elevated. The steady, laminar flow enabled use of the finite element method (FEM) to simulate the dissolution process using convective diffusion/drug dissolution theory. Simulations predicted the absolute magnitude of the release rate to within < 10% for all situations, and predicted the power law exponent of the dependence of release rate on flow rate with great accuracy. The current method is more general than compendial methods that provide a dissolving surface that is uniformly accessible to the dissolution medium, or a shear rate that is uniform across the entire dissolving surface. The current approach may be utilized to provide estimates of dissolution rates for any geometry and set of hydrodynamic conditions that can be numerically calculated.

Randomized, double-masked comparison of olopatadine ophthalmic solution, mometasone furoate monohydrate nasal spray, and fexofenadine hydrochloride tablets using the conjunctival and nasal allergen challenge models

BACKGROUND

It is presumed that exposure to allergens in the environment occurs through both the eyes and the nose. Allergic rhinoconjunctivitis is typically treated with a nasal spray or systemic antihistamine, neither of which may provide adequate relief of the ocular component of the disease.

OBJECTIVE

This study was designed to gain a better understanding of the physiologic interaction between the conjunctival and nasal mucosa and thus help establish a profile for the most effective ocular treatment in patients whose allergies have both an ocular and a nasal component.

METHODS

This was a single-center, randomized, double-masked clinical study using the conjunctival allergen challenge (CAC) and nasal allergen challenge (NAC) models. It compared the clinical signs and symptoms induced by CAC and NAC, the effects of drugs administered by 3 different routes, and the movement of fluorescein after instillation into the eye and nose (Jones test), and assessed levels of of inflammatory mediators in tears and nasal secretions. At visit l, subjects previously identified as CAC responders underwent NAC to determine the dose of allergen necessary to elicit a sufficient positive reaction. At visit 2, which took place 1 week later, subjects with a positive reaction at visit 1 were randomized to group A (CAC) or group B (NAC), and underwent challenge to confirm the allergen dose necessary to produce a positive reaction. Subjects who qualified were randomized to receive 1 of 3 treatments: olopatadine 0.1% ophthalmic solution, placebo nasal spray, and placebo tablets; mometasone furoate monohydrate 50-microg nasal spray, placebo topical solution, and placebo tablets; or fexofenadine hydrochloride 180-mg tablets, placebo topical solution, and placebo nasal spray. All study medications were administered according to their approved labeling: drops were administered twice daily in the eyes, and the nasal sprays and tablets were administered once daily. At visit 3, which took place 1 week after visit 2, subjects received study medication and 15 minutes later underwent CAC or NAC as before. The primary efficacy variables were ocular itching, ocular redness, and overall nasal symptoms (sneezing, rhino rrhea/postnasal drip, nasal pruritus, palatal pruritus, and nasal congestion) rated on standard scales. Peak nasal inspiratory flow (PNIF) was measured at each visit, and the Jones test was performed at visits 1 and 3. At baseline and after challenge at visits 2 and 3, tear and nasal lavage samples were collected from a subset of randomly selected subjects for analysis of eosinophil cationic protein and tryptase.

RESULTS

Seventy-three subjects (42 women, 31 men; mean age, 45.26 years [range, 21-73 years]) were screened, and all were randomized to treatment. Two subjects did not complete the study. CAC induced clinically significant (>1 unit difference) ocular and nasal signs and symptoms, whereas NAC induced clinically significant nasal signs and symptoms only. In group A, there was a greater reduction in ocular itching with olopatadine compared with mometasone and fexofenadine at 3 minutes (P = 0.003 and P = 0.008, respectively) and 5 minutes (P = 0.007 and P = 0.013) after challenge. Although the difference was not statistically significant, overall relief of conjunctival redness (average of 3 vessel beds) was greatest in the olopatadine group, followed by fexofenadine. In group B, prevention of total nasal symptoms was significantly greater with mometasone compared with fexofenadine at 20 minutes (P = 0.006) and 30 minutes (P = 0.014) after challenge. There were no statistically significant differences between treatment groups in nasal symptom scores at any time point after CAC. There were also no significant differences in PNIF between treatment groups. Fluorescein was present in nasal secretions within 5 minutes of being instilled into the eye; no fluorescein was detected in the eye after instillation into the nose.

CONCLUSIONS

In this study, exposure of the nasal mucosa to allergen resulted in allergic rhinitis, and exposure of the ocular the ocular surface to allergen resulted in conjunctivitis with a secondary effect in the nose. These results suggest movement of allergens, their mediators, and antiallergy drugs from the ocular surfaces into the nasal cavity, with no meaningful movement from the nasal cavity to the ocular surface. In this controlled model, both the systemic agent and the nasal spray failed to control ocular symptoms. The topical ophthalmic solution provided the most effective management of allergic ocular signs and symptoms, and the nasal spray was most effective for nasal symptoms. Combined use of a nasal spray and topical ophthalmic solution may provide maximal relief in patients whose allergies have both ocular and nasal components.

Features of mometasone furoate nasal spray and its utility in the management of allergic rhinitis

Mometasone furoate aqueous nasal spray (NS; Nasonex, Schering Corporation), is a synthetic corticosteroid approved for the prophylaxis and treatment of seasonal allergic rhinitis (SAR) and the treatment of perennial allergic rhinitis (PAR) in patients >or= 12 years of age, and for the treatment of SAR and PAR in children as young as 2 years of age. Studies demonstrate that mometasone furoate NS is a potent, clinically effective and well-tolerated intranasal corticosteroid with negligible systemic activity and which offers the convenience of once-daily dosing.

Systemic bioactivity of intranasal triamcinolone and mometasone in perennial allergic rhinitis

AIMS

To evaluate the systemic bioactivity of triamcinolone acetonide (TA) 220 micro g or mometasone furoate (MF) 200 micro g over 3 weeks in perennial allergic rhinitis.

METHODS

Twenty-seven patients received TA 220 micro g or MF 200 micro g once daily for 3 weeks with a 2 week placebo washout period prior to each randomized treatment. Measurements were made at baseline after each washout and after each randomized treatment, comprising overnight 10-h urinary cortisol corrected for creatinine (OUCC), 08.00 h plasma cortisol and 08.00 h serum osteocalcin.

RESULTS

There were no significant differences between baseline values prior to TA or MF, and for any outcome measures comparing randomized treatments to respective baseline values or comparing TA with MF. For OUCC compared with baseline, the geometric mean fold suppression (95% CI) was 1.02 (0.78, 1.33) for TA (2% decrease), 1.07 (0.80, 1.42) for MF (7% decrease), and 1.05 (0.79, 1.39) for TA vs MF (5% decrease).

CONCLUSIONS

Standard doses of TA or MF over 3 weeks showed no differences in systemic bioactivity markers compared with respective baseline values after placebo washout, and there were no differences between TA vs MF.

Mometasone furoate degradation and metabolism in human biological fluids and tissues

The in vitro metabolic and non-metabolic degradation kinetics of mometasone furoate (MF) was investigated in selected human biological fluids and subcellular fractions of tissues. Qualitative and quantitative differences in transformation profiles of MF were observed among human biological media. Degradation was the major event in plasma and urine with four new degradation products identified; A: 21-chloro-17alpha-hydroxy-16alpha-methyl-9beta,11beta-oxidopregna-1,4-diene-3,20-dione 17-(2-furoate), B: 9alpha,21beta-dichloro-11beta,21alpha-dihydroxy-16alpha-methylpregna-1,4,17,20-tetraen-3-one 21-(2-furoate), C: 21beta-chloro-21alpha-hydroxy-16alpha-methyl-9beta,11beta-oxidopregna-1,4,17,20-tetraen-3-one 21-(2-furoate), and D: 21-chloro-17alpha-hydroxy-16alpha-methyl-9beta,11beta-oxidopregna-1,4-diene-3,20-dione. A, B and C were predominant and D was minor in plasma while A and C were predominant in urine. Hydrolysis of the 17-ester bond of MF was not a major event in plasma. The turnover of MF in plasma was faster than that in phosphate buffers of pH 7.4. Metabolism of MF occurred primarily and rapidly in liver, appreciably in intestine, but negligibly in in vitro lung tissue. While 6beta-hydroxylation was a major metabolic pathway for MF in microsomes of both human liver and intestine, other parallel and subsequent metabolism pathways could also be involved. If these degradation and metabolic products are also formed and active in humans in vivo, both MF and its 'active' products need to be taken into account when determining the systemic bioavailability of MF and in establishing concentration-effect relationships with this drug.

Bioavailability and metabolism of mometasone furoate: pharmacology versus methodology

The degree of systemic exposure ofter inhalation of corticosteroids is of great clinical concern. For optimum outcome, the pulmonary deposition should be sufficiently high to produce the desired anti-inflammatory effect in the lungs, whereas the plasma concentrations due to the absorption of the corticosteroid from the lung and the gut should be minimal. Recently, it has been reported that inhaled mometasone furoate has a systemic bioavailability of less than 1%, which is much lower than other corticosteroids currently available. However, critical evaluation of the study methodology and results does not support this finding. A major shortfall of the study was an insufficient analytical sensitivity, resulting in a calculated average plasma concentration profile that was entirely below the limit of quantification. These numbers were generated by replacing all concentrations below the limit of quantification byzero and then calculating an average value. This procedure can lead to erroneous results and misinterpretation. Furthermore, the potential contribution of active metabolites needs to be adequately addressed in comparisons of inhaled corticosteroids. Reliable estimates of systemic drug exposure are critical in evaluating the real safety profiles and therapeutic index for inhaled corticosteroids that are effective in treating chronic asthma.

Inhaled mometasone furoate: a review of its use in adults and adolescents with persistent asthma

Mometasone furoate is a corticosteroid with relatively high in vitro potency. Recent randomised, double-blind, multicentre trials have assessed the efficacy of mometasone furoate delivered by dry powder inhaler over 12 weeks in adults and adolescents with mild to severe persistent asthma. Mometasone furoate 200 microg twice daily or 400 microg once daily in the morning or 200 microg once daily in the evening improved lung function, asthma symptom scores and use of rescue medication to a significantly greater extent than placebo in patients who had previously received only short-acting inhaled beta2-adrenoceptor agonists alone as treatment in 3 trials (n = 195 to 306). In studies in 227 to 733 patients with mild to moderate asthma who were receiving ongoing treatment with inhaled corticosteroids prior to enrolment, mometasone furoate 100 to 400 microg twice daily was consistently better at improving the above indicators of asthma than placebo. Mometasone furoate 100 to 200 microg twice daily was as effective as beclomethasone dipropionate 200 microg twice daily or budesonide 400 microg twice daily and mometasone furoate 200 microg twice daily was as effective as fluticasone propionate 250 microg twice daily. Mometasone furoate 400 or 800 microg twice daily was also consistently more effective than placebo in reducing oral corticosteroid dosages and improving lung function and asthma symptoms in 132 patients with oral corticosteroid-dependent asthma. Once daily administration of mometasone furoate 400 microg appears to be as effective at improving indicators of asthma as twice daily administration of 200 microg. Patients receiving mometasone furoate < or =800 microg/day and recipients of placebo experienced a similar overall incidence of adverse events considered to be related to treatment. The most common of these events were oral candidiasis, headache, pharyngitis and dysphonia. Mometasone furoate 100 to 400 microg twice daily, beclomethasone dipropionate 200 microg twice daily, budesonide 400 microg twice daily or fluticasone propionate 250 microg twice daily were similarly tolerated.

CONCLUSION

Inhaled mometasone furoate is well tolerated, with minimal systemic activity and is equally effective when administered as a divided dose or as a single daily dose. Use of the drug can result in a decrease in requirements for oral corticosteroids in patients with oral corticosteroid-dependent asthma and is as effective as other inhaled corticosteroids currently used in the treatment of mild to moderate persistent asthma. Thus mometasone furoate is suitable for the control of mild to severe persistent asthma in adults or adolescents.

Pharmacokinetics of intranasal corticosteroids

Topical administration of corticosteroids can reduce the total dose of corticosteroid required to treat the patient and minimize side effects. This logic has led to the development of intranasal corticosteroids (INCS) for allergic and perennial rhinitis. The second generation of these compounds includes beclomethasone dipropionate, budesonide, flunisolide, fluticasone propionate, mometasone furoate, and triamcinolone acetonide. There is evidence that the INCS are effective in rhinitis; however, there is concern about the potential for these compounds to cause growth suppression. In one study, beclomethasone dipropionate significantly reduced growth in children; however, treatment of children with mometasone furoate nasal spray for 1 year showed no signs of growth suppression. It is evident that the differences among INCS lie in their pharmacokinetics. Structural differences among the various INCS influence their metabolism. The goal of INCS therapy is to have a high ratio of topical to systemic activity. The drug delivery device, absorption of the drug, and drug distribution all contribute to effective topical activity of an INCS. In addition, individual drug metabolism and elimination (half-life and drug clearance) also contribute to the therapeutic index of a drug. Overall, the second-generation INCS cause minimal systemic effects at recommended doses.

Mometasone furoate: efficacy and safety in moderate asthma compared with beclomethasone dipropionate

BACKGROUND

Mometasone furoate (MF) is a new inhaled glucocorticoid administered by dry powder inhaler (DPI).

OBJECTIVE

MF-DPI was evaluated for safety and efficacy and compared with placebo DPI and beclomethasone dipropionate (BDP) administered by metered dose inhaler (MDI) in the treatment of patients with moderate persistent asthma.

METHODS

Eligible patients (n = 227), 13 to 75 years of age, maintained on inhaled glucocorticoids before entering the trial, were randomized to receive: MF-DPI, 100 microg, twice daily, MF-DPI, 200 microg, twice daily, BDP MDI, 168 microg, twice daily, or placebo in a 12-week, multicenter, double-blind study.

RESULTS

At endpoint, FEV1 (primary efficacy variable) significantly improved for all three active treatments compared with placebo (P < .01, all comparisons). The response to MF-DPI, 200 microg, twice daily treatment was approximately twice as large as the response to MF-DPI, 100 microg, twice daily or BDP MDI treatment, although the differences between these groups did not reach statistical significance. Secondary efficacy variables including PEFR, asthma symptoms, nocturnal awakenings, and albuterol use showed similar trends. The MF-DPI, 100 microg, twice daily and BDP MDI, 168 microg, twice daily treatment groups produced comparable results for all efficacy variables.

CONCLUSIONS

MF-DPI, 100 microg and 200 microg, twice daily were well-tolerated and significantly improved lung function and symptom control in the treatment of patients with moderate persistent asthma. In this study, MF-DPI, 200 microg, twice daily seemed to be the most effective dosage.

Comparison of once-daily to twice-daily treatment with mometasone furoate dry powder inhaler

BACKGROUND

Once-daily dosing with an effective inhaled corticosteroid (ICS) would likely enhance compliance and, therefore, aid in the management of asthma.

OBJECTIVE

Several once-daily dosing regimens of mometasone furoate (MF) administered by dry powder inhaler (DPI) were compared with a twice-daily dosing regimen in 286 patients with mild to moderate persistent asthma who were previously being treated with ICS.

METHODS

During a 2-week open-label phase, patients received MF-DPI, 200 microg twice daily. They were then randomized to continue MF-DPI, 200 microg twice-daily treatment or to receive MF-DPI, 200 microg once daily in the morning (AM), 200 microg once daily in the evening (PM), 400 microg once daily AM, or placebo as part of the 12-week, double-blind phase. The primary efficacy variable was the mean change from the baseline to endpoint (last evaluable observation) for FEV1.

RESULTS

Once-daily MF-DPI, 400 microg, AM maintained FEV1, and morning peak expiratory flow rate, FVC, FEF25%-75%, and asthma symptom scores, at levels similar to those for MF-DPI, 200 microg twice daily and significantly better than placebo. Once-daily MF-DPI, 200 microg, PM was effective in maintaining pulmonary function, but was less effective on other efficacy measures. In comparison to the other MF-DPI groups, once-daily MF-DPI, 200 microg, AM was not as effective overall. The incidence of local adverse events, including oral candidiasis, was low with all dosages.

CONCLUSIONS

Once-daily MF-DPI, 400 microg, AM was as effective as MF-DPI, 200 microg twice daily, whereas once-daily MF-DPI, 200 microg, was more effective when administered in the evening compared with morning, for patients receiving ICS therapy. Once-daily dosing offers an effective and convenient treatment that could aid compliance in the treatment of asthma.

Mometasone furoate has minimal effects on the hypothalamic-pituitary-adrenal axis when delivered at high doses

STUDY OBJECTIVES

To investigate the potential for mometasone furoate (MF) to exert systemic effects following administration by dry powder inhaler (DPI) or metered-dose inhaler (MDI).

DESIGN

Three randomized, evaluator-blind, placebo-controlled, parallel-group, 28-day studies.

PATIENTS

Adults with mild-to-moderate persistent asthma.

INTERVENTIONS

Study 1 (12 patients per treatment group; MF DPI at 200 microg bid, 400 microg qd, 800 microg qd, or 1,200 microg qd). Study 2 (16 patients per treatment group; MF DPI at 400 microg bid or 800 microg bid, or oral prednisone at 10 mg qd). Study 3 (16 patients per treatment group; MF MDI at 400 microg bid or 800 microg bid, or fluticasone propionate [FP] at 880 microg bid by MDI).

MEASUREMENTS AND RESULTS

Study 1. Plasma concentrations were near the lower limit of quantitation (50 pg/mL) at the MF DPI 400-microg qd dosage and approximately 250 pg/mL at the 1,200-microg qd dosage. The area under the curve for serum cortisol concentrations over 24 h (AUC(24)) was essentially unaltered at all doses. Study 2. Plasma levels over days 7 to 28 were 100.3 +/- 5.9 pg/mL (mean +/- SEM) for MF DPI 400 microg bid, and 181.0 +/- 10.9 pg/mL for 800 microg bid. Although there were relatively low levels of suppression (19 to 25%) at earlier time points for MF DPI 400 microg bid, serum cortisol AUC(24) levels at day 28 were similar to placebo. MF DPI 800 microg bid and oral prednisone both decreased serum cortisol AUC(24) levels at days 7 to 28 by 28.0 +/- 8.3% and 67.2 +/- 3.6%, respectively. The response to cosyntropin was normal in 15, 14, 11, and 1 of the patients in the placebo, MF DPI 400 microg bid, MF DPI 800 microg bid, and prednisone groups, respectively. Study 3. MF MDI caused even less systemic exposure than by DPI. MF MDI 800 microg bid (24.0 +/- 3.1%) and FP (51.7 +/- 3.8%) caused a significant decrease in serum cortisol AUC(24) on days 14 to 28. MF MDI 400 microg bid was similar to placebo treatment at all time points.

CONCLUSIONS

The MF 800-microg bid dosage (1,600 microg/d), which is twice the highest projected clinical dosage, represents the lower limit for consistently detectable systemic effects of MF.

Regional lung deposition of a technetium 99m-labeled formulation of mometasone furoate administered by hydrofluoroalkane 227 metered-dose inhaler

BACKGROUND

A new inhaled suspension formulation of mometasone furoate (MF), a potent corticosteroid with minimal systemic availability, has been developed for the treatment of asthma. This formulation is delivered by metered-dose inhaler (MDI) using the nonchlorofluorocarbon propellant hydrofluoroalkane 227 (HFA-227).

OBJECTIVE

The primary goal of this study was to determine the respiratory tract deposition of this formulation of MF. A secondary objective was to measure plasma concentrations of MF and a putative metabolite, 6-X-OH MF, to determine the systemic exposure to corticosteroid.

METHODS

This was a single-dose, open-label study in which 200 microg of technetium 99m (99mTc)-radiolabeled MF was administered to patients with asthma. Gamma scintigraphy was used to quantify lung, oropharyngeal, stomach, and MDI mouthpiece deposition patterns of MF.

RESULTS

Eleven patients, aged 21 to 47 years, with a history of asthma were enrolled in and completed the study. The mean (+/- SD) whole lung deposition of MF was 13.9%+/-5.7% of the metered (ex-valve) dose. The central lung zone received 5.3%+/-2.8% of the dose; the intermediate zone received 4.7%+/-1.9%; and peripheral lung deposition was 4.0%+/-1.5%. The mean (+/- SD) ratio of peripheral to central lung deposition was 0.8+/-0.2. Oropharyngeal deposition was 79.1%+/-8.7% of the ex-valve dose, with 6.3%+/-7.8% deposited on the MDI mouthpiece and 0.7%+/-0.5% exhaled. The majority of plasma samples taken for analysis of MF and 6-13-OH MF concentrations were below the limit of quantification (50 pg/mL) in all patients after inhalation of 200 microg 99mTc-labeled ME CONCLUSION: The lung deposition of MF when administered via HFA-227 MDI is comparable to the 10 to 20% lung deposition seen with other corticosteroid suspension for- mulations administered by MDI that have demonstrated effectiveness in the treatment of asthma.

Bioavailability and metabolism of mometasone furoate following administration by metered-dose and dry-powder inhalers in healthy human volunteers

These studies were conducted to assess the systemic bioavailability of mometasone furoate (MF) administered by both the dry-powder inhaler (DPI) and the metered-dose inhaler with an alternate propellant (MDI-AP). The pharmacokinetics of single doses (400 micrograms) of MF administered by intravenous (i.v.) and inhalation routes was assessed in a randomized, three-way crossover study involving 24 healthy volunteers. In a separate study, 6 healthy subjects were administered a single dose of tritiated (3H-) MF by DPI, and the radioactivity in blood, urine, feces, and expired air was determined. Following i.v. administration, MF was detected in all subjects for at least 8 hours postdose. The half-life (t1/2) following i.v. administration was 4.5 hours. In contrast, following DPI administration, plasma MF concentrations were below the limit of quantification (LOQ, 50 pg/mL) for many subjects (10 of 24), and the systemic bioavailability by this route was estimated to be less than 1%. Only two plasma samples following MDI-AP administration had plasma concentrations of MF above the LOQ indicating no detectable systemic bioavailability in 92% of the subjects. A separate study with 6 healthy male subjects administered a single dose of 3H-MF (200 microCi) by DPI revealed that much of the dose (approximately 41%) was excreted unchanged in the feces (0-72 hours), while that which was absorbed was extensively metabolized. These results indicate that inhaled MF has negligible systemic bioavailability and is extensively metabolized and should therefore be well tolerated in the chronic treatment of asthma.

Added relief in the treatment of acute recurrent sinusitis with adjunctive mometasone furoate nasal spray. The Nasonex Sinusitis Group

BACKGROUND

Intranasal glucocorticoids are effective in the treatment of allergic rhinitis. Their effectiveness as an anti-inflammatory adjunct in the treatment of acute recurrent sinusitis has not been adequately established in a controlled clinical study.

OBJECTIVE

The purpose of this study was to test the hypothesis that intranasal corticosteroid treatment produces additional relief in the treatment of acute sinusitis with oral antibiotics.

METHODS

Patients who were 12 years old and older with a history of recurrent sinusitis were treated while experiencing a new episode of acute sinusitis, which was diagnosed by symptoms and confirmed by computed tomography scan of the paranasal sinuses. Patients were treated for 21 days with amoxicillin clavulanate potassium and randomized to receive concurrent mometasone furoate nasal spray (MFNS; Nasonex [400 microg, twice daily]; n = 200 patients) or placebo spray (twice daily; n = 207 patients). Symptom scores for headache, facial pain, congestion, purulent rhinorrhea, postnasal drip, and cough were recorded at baseline and throughout treatment.

RESULTS

Baseline symptom scores showed a moderate level of symptom severity comparable in both groups. Patient-recorded twice daily symptom scores showed that adjunctive treatment with MFNS caused a significantly greater decrease in total symptom score (primary efficacy variable) and in individual scores of inflammatory symptoms associated with the obstruction process (headache, congestion, and facial pain) compared with placebo. Symptoms associated with the secretory processes were improved to a lesser degree. Therapy-related local adverse events were not significantly different between groups.

CONCLUSION

The addition of intranasal corticosteroid, MFNS 400 microg twice daily, to antibiotics significantly reduces symptoms of acute sinusitis compared with antibiotic treatment alone.

A dose-ranging study of mometasone furoate aqueous nasal spray in children with seasonal allergic rhinitis

BACKGROUND

The efficacy and safety of mometasone furoate aqueous nasal spray (MFNS; Nasonex) 200 microg once daily for the treatment and prophylaxis of seasonal allergic rhinitis (SAR) and treatment of perennial rhinitis have been demonstrated in adults. However, the dose response of MFNS in pediatric patients has not yet been characterized.

OBJECTIVE

This study was conducted to determine the dose-response relationship of 3 different doses of MFNS in a pediatric population.

METHODS

This was a multicenter, double-blind, active- and placebo-controlled study of 679 children 6 to 11 years of age with histories of SAR and documented positive skin test responses. Patients were randomized to one of the following treatment groups for 4 weeks: MFNS 25 microgram once daily, MFNS 100 microgram once daily, MFNS 200 microgram once daily, beclomethasone dipropionate 84 microgram twice daily (168 microgram/day), or placebo. Physician evaluations were performed at days 4, 8, 15, and 29, and patient evaluations were analyzed for days 1 to 15 and 16 to 29.

RESULTS

The mean reduction from baseline in physician-evaluated total nasal symptom scores at day 8 (the primary efficacy variable) was significantly greater in the MFNS and beclomethasone dipropionate groups than in the placebo group (P </=.02). No significant differences were observed among the 3 MFNS groups. However, as treatment continued, symptoms in patients treated with MFNS 100 or 200 microgram once daily continued to improve, whereas those treated with MFNS 25 microgram once daily demonstrated little further improvement. By day 29, MFNS 100 and 200 microgram once daily both were significantly more effective than MFNS 25 microgram once daily in relieving symptoms of SAR, but MFNS 200 microgram provided no additional benefit over MFNS 100 microgram. All doses of MFNS were well tolerated, and cosyntropin stimulation tests performed before and after treatment found no evidence of hypothalamic-pituitary-adrenal axis suppression.

CONCLUSION

These results indicate that the most appropriate therapeutic dosage of MFNS in the treatment of SAR in children 6 to 11 years of age is 100 microgram once daily. In addition, MFNS at doses up to 200 microgram once daily for 4 weeks was well tolerated and had no detectable effects on hypothalamic-pituitary-adrenal axis function.

Mometasone furoate. A review of its intranasal use in allergic rhinitis

Mometasone furoate is a synthetic corticosteroid which has been evaluated for intranasal use in the treatment of adults and children with allergic rhinitis. In several large, well-controlled clinical trials, mometasone furoate 200 micrograms administered once daily as an aqueous intranasal spray was significantly more effective than placebo in controlling the symptoms associated with moderate to severe seasonal or perennial allergic rhinitis. Mometasone furoate was as effective as twice-daily beclomethasone dipropionate or once-daily fluticasone propionate in the treatment of perennial allergic rhinitis, and was as effective as twice-daily beclomethasone dipropionate and slightly more effective than once-daily oral loratadine in the treatment of seasonal allergic rhinitis. Mometasone furoate was also as effective as twice-daily beclomethasone dipropionate or once-daily budesonide, and significantly more effective than placebo in the prophylaxis of seasonal allergic rhinitis. The onset of action of mometasone furoate was approximately 7 hours in patients with seasonal allergic rhinitis. Mometasone furoate was as well tolerated as beclomethasone dipropionate, fluticasone propionate and budesonide in clinical trials, with an overall incidence of adverse events similar to placebo. Adverse events were generally mild to moderate and of limited duration. The most common adverse events associated with mometasone furoate therapy were nasal irritation and/or burning, headache, epistaxis and pharyngitis. Intranasal or oral mometasone furoate had no detectable effect on hypothalamic-pituitary-adrenal axis function in studies of < or = 1 year in duration.

CONCLUSIONS

Mometasone furoate is a well tolerated intranasal corticosteroid with minimal systemic activity and an onset of action of < or = 7 hours. It is effective in the prophylaxis and treatment of seasonal allergic rhinitis and the treatment of perennial allergic rhinitis in patients with moderate to severe symptoms.