Systemic activity of inhaled beclomethasone dipropionate: a double-blind comparison of volume spacers

A review of the in vitro and in vivo valved holding chamber (VHC) literature with a focus on the AeroChamber Plus Flow-Vu Anti-static VHC

Valved holding chambers (VHCs) reduce the need for inhalation-actuation coordination with pressurized metered dose inhalers (pMDIs), reduce oropharyngeal drug deposition and may improve lung deposition and clinical outcomes compared to pMDIs used alone. While VHCs are thus widely advocated for use in vulnerable patient groups within clinical and regulatory guidelines, there is less consensus as to whether the performance differences between different VHCs have clinical implications. This review evaluates the VHC literature, in particular the data pertaining to large- versus small-volume chambers, aerosol performance with a VHC adjunct versus a pMDI alone, charge dissipative/conducting versus non-conducting VHCs, and facemasks, to ascertain whether potentially meaningful differences between VHCs exist. Inconsistencies in the literature are examined and explained, and relationships between in vitro and in vivo data are discussed. A particular focus of this review is the AeroChamber Plus® Flow-Vu® Anti-static VHC, the most recent iteration of the AeroChamber VHC family.

Short-Term Growth During Treatment with Inhaled Fluticasone Propionate/Formoterol, Fluticasone and Beclomethasone Treatment

BACKGROUND

Fluticasone propionate/formoterol (FP/FORM) is a pressurized metered-dose inhaler (pMDI; Flutiform^®) approved for use in adolescents and adults and under development for pediatric use.

OBJECTIVE

To compare short-term growth in asthmatic children treated with FP/FORM, FP pMDI with valved holding chamber, and beclomethasone dipropionate (BDP) in a breath-actuated device.

METHODS

Children with persistent asthma (n = 48; 5 to <12 years) participated in an assessor-blinded, randomized, three-way crossover trial with run in, wash out, and active treatment periods, each of 2 weeks duration. Interventions were FP/FORM 100/10 μg b.i.d. with an AeroChamber Plus^® Flow-Vu^® Spacer, FP pMDI (Flixotide^®) 100 μg b.i.d. with a Volumatic^® spacer, and extra-fine BDP breath-actuated inhaler (Aerobec^®/QVAR^® Autohaler^®) 100 μg b.i.d. Lower leg growth rate (LLGR) was measured by knemometry.

RESULTS

The least square (LS) mean difference in LLGR between FP/FORM and FP (per protocol population) was -0.006 mm/week (95% CI: -0.095 to 0.084; p < 0.001 for noninferiority [noninferiority margin -0.200 mm/week]). Both treatments elicited no change from baseline off-treatment growth rate. The LS mean treatment difference of FP/FORM versus BDP was 0.116 mm/week (95% CI: -0.004 to 0.235; p = 0.057) and of FP versus BDP 0.163 mm/week (95% CI: 0.078-0.249; p < 0.001). Results in the full analysis population were: FP/FORM versus FP -0.012 mm/week (95% CI: -0.080-0.056; p < 0.001); FP/FORM versus BDP 0.143 mm/week (95% CI: 0.064-0.222; p < 0.001); FP versus BDP 0.163 mm/week (95% CI: 0.093-0.233; p < 0.001).

CONCLUSIONS

FP/FORM pMDI with AeroChamber and FP pMDI with Volumatic spacer did not affect lower leg growth, measured by knemometry, in asthmatic children. Conversely, extra-fine BDP from a breath-actuated inhaler resulted in short-term growth suppression.

Knemometry is more sensitive to systemic effects of inhaled corticosteroids in children with asthma than 24-hour urine cortisol excretion

BACKGROUND

Pharmacodynamic assessment of the systemic effect of inhaled corticosteroids (ICSs) is often done by measuring 24-hour urine free cortisol (UFC) excretion. Knemometry assessing short-term lower-leg growth rate (LLGR) is a more rarely used alternative.

OBJECTIVE

The primary aim of this study was to compare the sensitivity of LLGR and 24-hour UFC excretion for evaluating systemic exposure to ICSs in prepubertal children with asthma. The secondary aim was to evaluate factors influencing the precision of LLGR calculated by the traditional 1 leg nonparametric method versus a new 2 leg parametric method.

METHODS

The study evaluated 60 children with mild asthma aged 5 to 12 years participating in a randomized controlled trial of ICSs with longitudinal concomitant assessments of LLGR and 24-hour UFC excretion. The sensitivity of the safety assessments was analyzed by comparing LLGR and 24-hour UFC in the placebo run-in period with values in the ICS treatment period by using paired t tests. Factors with a potential influence on LLGR were analyzed by means of ANOVA and the Levene test of homogeneity.

RESULTS

The mean LLGR was significantly reduced during the ICS versus placebo run-in periods: 0.18 mm/wk (SD, 0.55 mm/wk) versus 0.45 mm/wk (SD, 0.39 mm/wk), with a mean difference of 0.27 mm/wk (95% CI, 0.05-0.48 mm/wk; P = .02). In contrast, there was no difference in 24-hour UFC excretion: 6.91 nmol/mmol (SD, 4.67 nmol/mmol) versus 7.58 nmol/mmol (SD, 6.17 nmol/mmol), with a mean difference of 0.67 nmol/mmol (95% CI, -1.13 to 2.48 nmol/mmol; P = .46). We observed no significant difference in parametric determined LLGR caused by the child's age or sex, investigator, or season of measurement, whereas some differences were observed for the nonparametric LLGR.

CONCLUSION

These findings suggest that knemometry is a more sensitive pharmacodynamic measure of systemic effects of ICSs than 24-hour UFC excretion and that a parametric determination of LLGR increases the sensitivity of the method. These findings should be considered by legislative authorities in the future.

Extra-fine particle inhaled corticosteroids, pharma-cokinetics and systemic activity in children with asthma

During recent years, extra-fine particle inhaled corticosteroids with a median aerodynamic diameter ≤2 μm have been introduced in the treatment of asthma. The aim of this paper was to review pharmacokinetics and systemic activity of extra-fine particle hydroalkane pressurized metered dose inhaled (pMDI) ciclesonide and beclomethasone dipropionate in children. A literature review was performed. Systemic bioavailability of oral and pulmonary deposition of extra-fine ciclesonide and beclomethasone dipropionate was 52% and 82%, the half-life in serum 3.2 and 1.5 h and first-pass hepatic metabolism >99% and 60%, respectively. Secondary analyses of urine cortisol/creatinine excretion found no effects of ciclesonide pMDI between 40 and 320 μg/day or of beclomethasone dipropionate pMDI between 80 and 400 μg/day. Ciclesonide pMDI 40, 80 and 160 μg/day caused no effects on short-term lower leg growth rate as assessed by knemometry. Ciclesonide 320 μg/day was associated with a numerically short-term growth suppression equivalent to 30% which was similar to 25% and 36% suppression caused by beclomethasone dipropionate HFA and CFC 200 μg/day, respectively. Consistent with the differences in key pharmacokinetic features, beclomethasone dipropionate is associated with a systemic activity detected by knemometry at a lower dose than ciclesonide. Whether that correlates with a clinically important difference remains to be explored. Assessments of systemic activity of beclomethasone dipropionate <200 μg/day and of ciclesonide >180 μg/day as well as head-to-head comparisons are warranted. Preferably, such studies should apply the sensitive method of knemometry.

A Comparison of Short-Term Growth During Treatment with Two Dry Powder Combinations of Inhaled Corticosteroids and Long-Acting β₂-Agonists

BACKGROUND

A combination of the inhaled corticosteroid budesonide and the long-acting β2-agonist formoterol has been formulated in a novel dry powder inhaler, Spiromax(®). The objective was to compare lower leg growth in children with asthma treated with inhaled budesonide+formoterol (BF) delivered from the Spiromax inhaler with BF from the Symbicort Turbohaler(®).

METHODS

Prepubescent children with persistent asthma (n=75, aged 6-11 years) were included in a randomized, double-blind, double-dummy, placebo-controlled, three-way crossover study with active treatment and placebo periods of 2 weeks duration. Lower leg length was measured every second week. As a secondary outcome parameter, 24-hr urine was collected for assessment of free cortisol. Interventions were dry powder BF 160+9 μg twice daily (b.i.d.; delivered dose) from the Spiromax inhaler and dry powder BF 200+12 μg b.i.d. (metered dose) from the Symbicort Turbohaler.

RESULTS

The least squares mean difference in lower leg growth rates (LLGR) between BF Spiromax and Symbicort Turbohaler was -0.086 mm/week [95% confidence interval (CI) -0.203, 0.032]. The pre-specified non-inferiority margin was -0.200 mm/week, so the lower limit of the 95% CI was just outside this margin. The difference between BF Spiromax and placebo was -0.20 mm/week (95% CI: -0.322, 0.086); p<0.001), between Symbicort Turbohaler and placebo -0.118 mm/week (95% CI: -0.236, -0.001; p=0.048). No statistically significant differences were seen in urine free cortisol assessments.

CONCLUSIONS

As the lower limit of the CI of LLGR was marginally outside of the pre-specified non-inferiority margin between BF Spiromax 160+9 μg b.i.d. and Symbicort Turbohaler 200+12 μg b.i.d., non-inferiority could not be demonstrated. Further studies may be needed for comparison of systemic activity of BF Spiromax and Symbicort Turbohaler in children before firm conclusions about their comparability may be drawn.

Inhaled corticosteroids for asthma: on-demand or continuous use

Continuous inhaled corticosteroid treatment is highly effective in children and adults with mild persistent asthma, although some therapeutic benefits are not lost if treatment is delayed. Many patients do not adhere to continuous treatment with inhaled corticosteroids, but rather take them intermittently, usually at the time of increased symptoms. Based on these observations it has been proposed that for patients with mild persistent asthma inhaled corticosteroids should be used on-demand when symptoms are troublesome, rather than on a continuous basis. The article reviews the pharmacological properties of inhaled corticosteroids used in clinical trials of on-demand treatment, as well as the evidence for the efficacy and safety of on-demand compared with continuous inhaled corticosteroid treatment of mild persistent asthma in adults and children. The place of on-demand treatment with inhaled corticosteroids in the management of asthma is discussed, as well as future directions for different management strategies for this group.