Aims To determine the basal pharmacokinetics, lung uptake and plasma cortisol suppression for two commonly prescribed inhaled corticosteroids. Methods Twenty-one subjects (13 healthy and 8 mild asthmatic patients) received uticasone propionate via a chloro¯uorocarbon-propelled pressurized metered-dose inhaler (pMDI) (healthy subjects only) and Diskus 1 and budesonide via Turbuhaler 1 , 1000 mg twice daily for 7 days. Intravenous doses (200 mg) of both compounds were used as references. Plasma concentrations of¯uticasone and budesonide were determined during 48 h by liquid chromatography plus tandem mass spectrometry (LC-MS-MS). Plasma concentrations of cortisol were determined by LC-MS every second hour for 24 h at baseline, and following each treatment. Results The volume of distribution was found to be larger and the elimination half-life and mean absorption time longer for¯uticasone than for budesonide. The systemic availability of budesonide via Turbuhaler (39%) was signi®cantly higher than that of uticasone via Diskus (13%) (ratio 3.0 [2.5, 3.6] with 95% con®dence interval [CI]), and via pMDI (21%) (ratio 1.8 [1.3, 2.3]). In addition, at steady state the systemic availability of¯uticasone via pMDI was signi®cantly higher than via Diskus (ratio 1.6 [1.1, 2.2]). The lung deposition of budesonide via Turbuhaler was 2.2-fold [1.7, 2.9] higher than that of¯uticasone pMDI and 3.4-fold [2.8, 4.0] higher than that of uticasone Diskus. In addition, the lung deposition of¯uticasone via pMDI was 1.5-fold [1.1, 2.9] higher than that via the Diskus inhaler. Plasma cortisol (24 h) was signi®cantly reduced vs baseline for all three treatments. The cortisol concentration vs baseline was 12% for¯uticasone pMDI, which was signi®cantly lower (ratio 0.32 [0.24, 0.42]) than that for¯uticasone Diskus (39%), and for budesonide Turbuhaler (46%) (ratio 0.27 [0.21, 0.37]). The plasma cortisol concentration did not differ signi®cantly between treatments with¯uticasone Diskus and budesonide Turbuhaler (ratio 0.87 [0.65; 1.15]). Conclusions Budesonide and¯uticasone differ in their pharmacokinetic properties in that although clearance is the same, the rate of uptake and elimination is slower for uticasone. Despite a signi®cantly higher pulmonary availability of budesonide via Turbuhaler, the plasma cortisol suppression is less than that of¯uticasone via pMDI and similar to that of¯uticasone via Diskus. There is no indication of any difference between healthy subjects and mild asthmatic patients in the pharmacokinetics and plasma cortisol suppression of¯uticasone and budesonide.

Aims The present study was undertaken to see whether the difference in plasma cortisol suppression between single and repeated dosing of fluticasone propionate (FP) can be explained by systemic accumulation. Methods Twelve healthy subjects (six women) were given, in a crossover fashion, a single dose inhalation (1000 mg ) of FP via DiskhalerA and repeated inhalations (1000 mg twice daily) every 12 h during 7 days. There was a washout period of 2 weeks between the treatments. An intravenous dose of 20 mg FP was given as a reference. Plasma concentrations of FP for each treatment were determined by liquid chromatography plus tandem mass spectrometry. Plasma cortisol after the inhaled doses was determined using an immunoassay and was compared with baseline values. Results The average plasma concentration of FP was about 1.7 times higher after multiple inhalations than after a single dose. Systemic availability, mainly attributable to pulmonary deposition, was 15.6 [13.6-18.0]% of the nominal dose. Daytime plasma cortisol suppression vs baseline was 47 [20-65]% and 95 [93-97]% for the single and repeated doses, respectively. Conclusions To conclude, a slow elimination of FP leads to accumulation during repeated dosing. This accumulation may explain the marked decrease in plasma cortisol seen during treatment with fluticasone propionate within the clinical dose range.

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BackgroundInteractions between Th1 and Th2 immune responses are of importance to the onset and development of allergic disorders. A Toll-like receptor 7 agonist such as AZD8848 may have potential as a treatment for allergic airway disease by skewing the immune system away from a Th2 profile.ObjectiveTo evaluate the efficacy and safety of intranasal AZD8848.MethodsIn a placebo-controlled single ascending dose study, AZD8848 (0.3-600 μg) was given intranasally to 48 healthy subjects and 12 patients with allergic rhinitis (NCT00688779). In a placebo-controlled repeat challenge/treatment study, AZD8848 (30 and 60 μg) was given once weekly for five weeks to 74 patients with allergic rhinitis out of season: starting 24 hours after the final dose, daily allergen challenges were given for seven days (NCT00770003). Safety, tolerability, pharmacokinetics, and biomarkers were monitored. During the allergen challenge series, nasal symptoms and lavage fluid levels of tryptase and α2-macroglobulin, reflecting mast cell activity and plasma exudation, were monitored.ResultsAZD8848 produced reversible blood lymphocyte reductions and dose-dependent flu-like symptoms: 30–100 μg produced consistent yet tolerable effects. Plasma interleukin-1 receptor antagonist was elevated after administration of AZD8848, reflecting interferon production secondary to TLR7 stimulation. At repeat challenge/treatment, AZD8848 reduced nasal symptoms recorded ten minutes after allergen challenge up to eight days after the final dose. Tryptase and α2-macroglobulin were also reduced by AZD8848.ConclusionsRepeated intranasal stimulation of Toll-like receptor 7 by AZD8848 was safe and produced a sustained reduction in the responsiveness to allergen in allergic rhinitis.Trial registrationNCT00688779 and NCT00770003 as indicated above.

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