RESUMO
AIMS: To investigate the pharmacokinetics and effects on the hypothalamic-pituitary-adrenal (HPA) axis of mometasone furoate (MF), fluticasone propionate (FP) and fluticasone furoate (FF). METHODS: Study 1: Fourteen healthy participants received inhaled and intravenous MF (inhaled dose via Twisthaler) and FP (inhaled dose via Diskus), both given at 400 µg, using a randomised, single-dose, four-way crossover design. Study 2: Twenty-seven participants with mild to moderate asthma, who discontinued their corticosteroid medication for 5 days to obtain a baseline 24 h serum cortisol, received inhaled MF Twisthaler and FP Diskus, both given at 400 µg twice daily (BID), using a randomised, 14-day repeat dose, two-way crossover design. Study 3: Forty-four healthy participants were randomised to a double-blind, placebo-controlled, five-period crossover study where the following treatments were administered via the inhaled route for 7 days: FP Diskus (250, 500, 1000 µg BID), FF Diskus (100, 200, 400, 800, 1600 µg once daily [QD]) or placebo Diskus. In each study, 24-h serial blood samples were collected and assayed to assess concentrations of MF, 6ß-hydroxy mometasone, mometasone, FP, FF and cortisol. Pharmacokinetic and serum cortisol parameters were estimated as geometric means and 95% confidence intervals (CI). RESULTS: Study 1: For intravenous MF and FP, respectively: absolute bioavailability was 11.4% (95% CI: 7.5, 17.6) and 7.8% (6.3, 9.6); plasma clearance was 47 L/h (41, 52) and 60 L/h (52, 69); half-life was 7.4 h (6.9, 8.0) and 7.2 h (6.5, 8.0); and volume of distribution was 499 L (439, 567) and 623 L (557, 698). Inhalation of single dose MF or FP did not significantly affect serum cortisol (<10% reduction from baseline), whereas intravenous administration of MF or FP each changed serum cortisol by approximately -50% from baseline. Study 2: For MF and FP, respectively: area under the curve up to the last measurable concentration on Day 1 was 421 pg h/mL (270, 659) and 248 pg h/mL (154, 400), and on Day 14 was 1092 pg h/mL (939, 1269) and 591 pg h/mL (501, 696); absolute bioavailability was 12.8% (11.2, 14.2) and 8.9% (7.7, 10.2). On Day 14, 24-h serum cortisol change from baseline was -35% (-44%, -26%) and -18% (-28%, -5%) for MF and FP, respectively; the reduction was significantly greater for MF than FP (ratio for geometric adjusted mean serum cortisol concentration: 1.28 [1.04, 1.56]). Low plasma concentrations of 6ß-hydroxy mometasone were detected after intravenous dosing (Study 1) and after multiple inhaled dosing (Study 2); mometasone was not detected in any samples. Study 3: Inhaled FP and FF had similar systemic bioavailability estimates (12.0% [11.0, 13.2] and 15.0% [12.0, 17.3], respectively), but a differential effect on the HPA axis which was in agreement with the known 1.7-fold higher glucocorticoid receptor-binding affinity of FF versus FP. However, for FP 250 µg BID and FF 100, 200 and 400 µg QD, reduction in serum cortisol was not significantly different from placebo. For higher doses, FP 500 and 1000 µg BID, and FF 800 and 1600 µg QD, changes in serum cortisol concentration relative to placebo were -30%, -70%, -41% and -90%, respectively. Repeat inhaled dosing of FP 1000 µg/day (within the therapeutic dose range) resulted in comparable cortisol suppression to MF in the therapeutic range (30% reduction); whereas for FF this occurred at more than 3-fold above the therapeutic dose range (644 µg/day). CONCLUSIONS: Single inhaled and intravenous doses of MF and FP (400 µg) resulted in similar bioavailability and reductions in serum cortisol. Repeat dosing of inhaled MF and FP in the therapeutic range (800 µg/day) resulted in greater systemic exposure for MF, and a 35% reduction in serum cortisol that was 2-fold greater than for FP. The higher glucocorticoid receptor-binding affinity and bioavailability, lower clearance and the presence of active metabolites may contribute to the greater systemic exposure and effect on cortisol for MF. Repeat dosing of inhaled FP and FF resulted in similar systemic bioavailability but differed in terms of the dose required for comparable cortisol suppression to MF in the therapeutic range. Unlike FP and FF, MF has active metabolites that may contribute to its systemic effects, while device/formulation performance differences also exist between MF-containing products.
Assuntos
Sistema Hipotálamo-Hipofisário , Receptores de Glucocorticoides , Humanos , Fluticasona/farmacologia , Furoato de Mometasona/farmacologia , Estudos Cross-Over , Sistema Hipófise-Suprarrenal , Androstadienos/farmacologia , Administração por Inalação , Hidrocortisona/farmacologia , Método Duplo-CegoRESUMO
BACKGROUND: Chronic obstructive pulmonary disease (COPD) has a significant negative impact on quality of life and increases the risk of premature death. Umeclidinium is a long-acting muscarinic receptor antagonist in development for the treatment of COPD with the aim to broaden treatment options for clinicians and patients by providing improved symptom control. OBJECTIVE: To characterize the safety, tolerability, pharmacokinetics and pharmacodynamics of single and repeat inhaled doses of umeclidinium in healthy subjects. STUDY DESIGN: Two randomized, placebo-controlled, ascending-dose studies were conducted in healthy ipratropium bromide-responsive subjects. In the single-dose study, subjects (n = 20) received umeclidinium (10-350 µg), tiotropium bromide 18 µg and placebo in a crossover dosing schedule. In this study, lung function was assessed for 24 h by measuring specific airways conductance (sGaw) and forced expiratory volume in 1 s (FEV1). In the repeat-dose study, subjects (n = 36) received umeclidinium (250-1,000 µg) and placebo for 14 days in a parallel-group schedule. RESULTS: Adverse events (AEs) were reported in five subjects (single-dose study) and 23 subjects (repeat-dose study); none were serious. In both studies, no abnormalities in 12-lead electrocardiogram parameters, 24-h Holter monitoring or lead II monitoring were reported as AEs. Umeclidinium was rapidly absorbed following single-dose administration [time to reach the maximum plasma concentration (tmax) 5-15 min] and repeat-dose administration (tmax 5-7 min). Following repeat dosing, the geometric mean plasma elimination half-life was approximately 27 h and statistically significant accumulation was observed for the area under the plasma concentration-time curve, maximum plasma concentration and cumulative amount of unchanged drug excreted into the urine at 24 h (range 1.5- to 4.5-fold). Umeclidinium at doses of 100 µg and above, and tiotropium bromide demonstrated statistically significant bronchodilatory effects relative to placebo at 12 h post-dosing, which lasted up to 24 h for umeclidinium 350 µg and for tiotropium bromide. Relative to placebo, these increases in sGaw were 24-34 % at 12 h post-dose and 13 % at 24 h post-dose. Increases in FEV1 achieved statistical significance at 12 and 24 h for umeclidinium 100 µg and 350 µg compared with placebo. CONCLUSION: Umeclidinium was well tolerated and demonstrated bronchodilatory effects in healthy subjects for up to 24 h. These bronchodilatory effects can be potentially clinically important in patients with airway obstruction such as COPD. The data obtained have informed dose selection for subsequent trials in subjects with COPD.
Assuntos
Antagonistas Muscarínicos/farmacologia , Quinuclidinas/farmacologia , Administração por Inalação , Adulto , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Antagonistas Muscarínicos/efeitos adversos , Antagonistas Muscarínicos/farmacocinética , Placebos , Quinuclidinas/efeitos adversos , Quinuclidinas/farmacocinética , Adulto JovemRESUMO
BACKGROUND: GSK233705 is an inhaled, long-acting muscarinic antagonist in development for the treatment of chronic obstructive pulmonary disease (COPD). This study was performed to see if the addition of GSK233705 to salmeterol would provide greater bronchodilation than salmeterol or tiotropium alone in COPD. METHODS: In an incomplete-block, three-period, crossover design, dually responsive patients received three of the following five treatments: GSK233705 20 µg plus salmeterol 50 µg twice-daily; GSK233705 50 µg plus salmeterol 50 µg twice-daily; salmeterol 50 µg or placebo, each twice-daily; and tiotropium 18 µg or placebo once-daily for 7 days. Each treatment period was separated by a 14-day washout. The primary efficacy endpoint was morning (trough) forced expiratory volume in 1 second (FEV(1)) on Day 8, following 7 days of treatment. Secondary endpoints included pulmonary function, plethysmography, pharmacokinetics of GSK233705 and salmeterol, adverse events (AEs), electrocardiograms (ECGs), vital signs, and laboratory parameters. RESULTS: A total of 47 patients were randomized. The mean % predicted normal postbronchodilator FEV(1) was 55% at screening. Compared with placebo (n = 24), the adjusted mean change from baseline in trough FEV(1) on Day 8 was 215 mL higher with GSK233705 20 µg + salmeterol (n = 23) and 203 mL higher with GSK233705 50 µg + salmeterol (n = 27), whereas with salmeterol (n = 27) and tiotropium (n = 28) the changes were 101 mL and 118 mL higher, respectively. The primary efficacy results were supported by the results from the other secondary lung function assessments. AEs were reported by similar proportions of patients across the treatment groups, with headache the most frequently reported treatment-related AE reported by one subject receiving each of GSK233705 20 µg + salmeterol, tiotropium, and placebo. No significant differences were seen in vital signs, ECGs, or laboratory parameters between the groups. CONCLUSION: The addition of GSK233705 to salmeterol in partially reversible COPD patients resulted in greater bronchodilation than salmeterol or tiotropium alone and was well tolerated.