A randomized primary care trial of steroid titration against mannitol in persistent asthma: STAMINA trial.

BACKGROUND: We compared titrating inhaled corticosteroid (ICS) against mannitol airway hyperresponsiveness (AHR) or a reference strategy (control) based on symptoms, reliever use, and lung function in primary care. METHODS: One hundred sixty-four patients with persistent asthma were randomized in parallel group fashion following an initial ICS tapering. Subsequent ICS doses (as ciclesonide) were titrated against either the provocative dose of mannitol causing a 10% fall in FEV(1) (PD(10)) (AHR strategy) or a control group (reference strategy) over a 1-year period. RESULTS: One hundred nineteen participants (n = 61 AHR, n = 58 control) completed the study. Time to first mild exacerbation was not significantly different: hazard ratio, 1.29; 95% CI, 0.716-2.31; P = .40. Although there were 27% fewer total number of mild exacerbations over 12 months in AHR vs control groups (n = 84 vs n = 115, P = .03), there was no difference in severe exacerbations (n = 12 vs n = 13). No other significant differences were seen between groups with the exception of mannitol PD(10) and ICS dose. There was a 1.52 (95% CI, 0.61-2.42; P = .001) doubling dose difference in mannitol PD(10) between AHR vs control groups. The final mean daily ciclesonide dose was higher (P < .0001) in AHR vs control groups (514 µg vs 208 µg), with no associated significant suppression of overnight urinary cortisol/creatinine. Significant improvements were seen within the AHR group but not the control group for the provocative concentration of methacholine causing a 20% fall in FEV(1) (P < .05), salivary eosinophilic cationic protein (P < .05), exhaled nitric oxide (P < .05), symptoms (P < .005), and reliever use (P < .001). CONCLUSIONS: Mannitol challenge was well tolerated in a primary care setting. Using mannitol resulted in exposure to a higher dose of ciclesonide, which was associated with equivocal effects on exacerbations without associated adrenal suppression. Large-scale trials using mannitol in patients with more severe disease may now be warranted to further define its role. TRIAL REGISTRATION: ClinicalTrials.gov; No.: NCT01216579; URL: www.clinicaltrials.gov.

Fluticasone/Salmeterol combination confers benefits in people with asthma who smoke.

BACKGROUND: Smoking induces airway inflammation and relative resistance to inhaled steroids. The objective of this study was to evaluate the effects on airway hyperresponsiveness of adding salmeterol to fluticasone vs doubling the dose of fluticasone in patients with asthma who smoked and patients with asthma who did not smoke. METHODS: Sixteen patients with mild to moderate persistent asthma who did not smoke and 15 such patients who smoked completed a double-blind, randomized, placebo-controlled crossover study. They received either a fluticasone/salmeterol combination (FP/SM) (125/25 µg) two puffs bid (plus fluticasone placebo), or active fluticasone (250 µg) two puffs bid (plus FP/SM placebo), for 2 weeks each, with baselines after 1-week to 2-week run-in and washout periods. The primary outcome was the change from baseline in the provocative concentration of methacholine required to produce a 20% fall in FEV(1) (PC(20)). RESULTS: In the patients who did not smoke, there were similar improvements in the methacholine PC(20) with the use of fluticasone and FP/SM. The patients who smoked gained a benefit from FP/SM but not fluticasone, amounting to a PC(20) difference of 1.6 doubling dilutions (95% CI, 1.0-2.2), P < .01. The provocative dose of mannitol required to produce a 15% fall in FEV(1) (PD(15)) showed greater improvements with FP/SM than fluticasone in both patients who smoked and did not smoke. Similar differences in airway caliber between those who smoked and did not smoke were observed in FEV(1) and airway resistance. CONCLUSIONS: FP/SM confers greater improvements in airway hyperresponsiveness and airway caliber in patients with asthma who smoke compared with double the dose of fluticasone. We hypothesize that in the presence of relative steroid resistance, the smooth muscle stabilization conferred by salmeterol is of greater clinical importance in patients who smoke than in those who do not smoke. TRIAL REGISTRY: ClinicalTrials.gov: No.: NCT00830505; URL: www.clinicaltrials.gov.

Pharmacokinetic and pharmacodynamic comparison of hydrofluoroalkane and chlorofluorocarbon formulations of budesonide.

AIMS: A hydrofluoroalkane formulation of budesonide pressurized metered-dose inhaler has been developed to replace the existing chlorofluorocarbon one. The aim of this study was to evaluate the pharmacokinetic and pharmacodynamic characteristics of both formulations. METHODS: Systemic bioavailability and bioactivity of both hydrofluoroalkane and chlorofluorocarbon pressurized metered-dose inhaler formulations at 800 µg twice daily was determined during a randomized crossover systemic pharmacokinetic/pharmacodynamic study at steady state in healthy volunteers. Measurements included the following: plasma cortisol AUC(24h) [area under the concentration-time curve (0-24 h)], budesonide AUC(0-12h) and C(max) . Clinical efficacy was determined during a randomized crossover pharmacodynamic study in asthmatic patients receiving 200 µg followed by 800 µg budesonide via chlorofluorocarbon or hydrofluoroalkane pressurized metered-dose inhaler each for 4 weeks. Methacholine PC(20) (primary outcome), exhaled nitric oxide, spirometry, peak expiratory flow and symptoms were evaluated. RESULTS: In the pharmacokinetic study, there were no differences in cortisol, AUC(0-12h) [area under the concentration-time curve (0-12 h)], T(max) (time to maximum concentration) or C(max) (peak serum concentration) between the hydrofluoroalkane and chlorofluorocarbon pressurized metered-dose inhaler. The ratio of budesonide hydrofluoroalkane vs. chlorofluorocarbon pressurized metered-dose inhaler for cortisol AUC(24h) was 1.02 (95% confidence interval 0.93-1.11) and budesonide AUC(0-12h) was 1.03 (90% confidence interval 0.9-1.18). In the asthma pharmacodynamic study, there was a significant dose response (P < 0.0001) for methacholine PC(20) (provocative concentration of methacholine needed to produce a 20% fall in FEV(1) ) with a relative potency ratio of 1.10 (95% confidence interval 0.49-2.66), and no difference at either dose. No significant differences between formulations were seen with the secondary outcome variables. CONCLUSIONS: Hydrofluoroalkane and chlorofluorocarbon formulations of budesonide were therapeutically equivalent in terms of relative lung bioavailability, airway efficacy and systemic effects.

Systemic bioavailability of hydrofluoroalkane (HFA) formulations of fluticasone/salmeterol in healthy volunteers via pMDI alone and spacer.

AIM: To compare a test version of HFA fluticasone/salmeterol (FP/SM) combination inhaler (Neolab, UK) with the reference product Seretide (GlaxoSmithKline, UK). METHODS: An in vitro Anderson cascade impactor was used to compare the fine particle dose (<4.7 microm). Two separate randomized cross-over studies were performed to compare the systemic bioavailability of test vs. reference (T vs. R) formulations of FP/SM 250/25 microg pMDI in healthy volunteers. In study 1 blood pharmacokinetic analysis using oral charcoal block was performed over 24 h following a single dose of four puffs via pMDI alone. In study 2 systemic bioactivity was measured following single doses of four and eight puffs via a spacer device: serum potassium (K(+)) to reflect SM, and overnight urinary cortisol : creatinine (OUCC) for FP. An early pharmacokinetic profile was also assessed over 120 min. RESULTS: The in vitro fine particle dose was similar for test vs. reference pMDI alone and via spacer. The results of both studies were consistent: No significant differences between formulations were seen in terms of FP kinetics. Analysis of SM kinetics revealed superiority of the test product. No significant dose-response or difference in T : R ratio was noted for OUCC. Fall in K(+) revealed a significant dose-response with a non-significant T : R ratio. CONCLUSIONS: The in vitro fine particle dose may not predict pharmacokinetic and systemic pharmacodynamic outcomes. Single dosing studies with fluticasone/salmeterol 250/25 microg via pMDI or with spacer showed pharmacokinetic equivalence with FP, but not SM. No significant difference between formulations was seen with either adrenal suppression or hypokalaemia.

Paradoxical trough effects of triple therapy with budesonide/formoterol and tiotropium bromide on pulmonary function outcomes in COPD.

BACKGROUND: Lowest receptor occupancy for a drug occurs at trough prior to the next dose. Previous studies have focused on the effects of triple therapy at peak dose intervals using forced expiratory maneuvers. Impulse oscillometry (IOS) and body plethysmography (PLETH) are more sensitive than spirometry to assess inhaled therapies in COPD. METHODS: Nineteen patients with COPD (FEV(1)/FVC ratio < 0.7; FEV(1) < 60%) completed a double-blind randomized crossover trial of tiotropium 18 microg/d or placebo for 2 weeks each, with a 1-week washout. Prior to this procedure, there was a nonrandomized 4 week run-in of budesonide/formoterol 200/6 2 puffs bid, which continued throughout the study. Spirometry, IOS, and PLETH were performed both before pre- and post-budesonide/formoterol run-in and at trough following the first and last dose of tiotropium (ie, 24 h posttiotropium and 12 h post-budesonide/formoterol). RESULTS: Mean +/- SEM for age and FEV(1) were 65 +/- 2 years and 42 +/- 2%, respectively. Following initial budesonide/formoterol, there were no significant changes in spirometry; however, all measures of IOS and PLETH deteriorated (P < .01 for all outcomes). Compared with placebo, tiotropium was additive to budesonide/formoterol after single and chronic dosing measured by FEV(1) (P < .001 and P = .014, respectively) and forced expiratory flow, midexpiratory phase (P = .001; P= .026), whereas specific airway resistance, reactance, resonant frequency, and area under the reactance curve showed additive benefits at a single dose only. CONCLUSIONS: Budesonide/formoterol caused an unexpected worsening of IOS and PLETH outcomes compared with a washed-out baseline in the nonplacebo-controlled run-in. This finding was not observed with spirometry. Subsequent addition of tiotropium improved lung function with all techniques after a single dose and for spirometry after chronic dosing. These paradoxical findings may reflect beta2-adrenoceptor downregulation and muscarinic 3 receptor cross talk. Placebo-controlled studies are required to explore this result.