Pharmacokinetics of Beclomethasone Dipropionate Delivered by Breath-Actuated Inhaler and Metered-Dose Inhaler in Healthy Subjects

BACKGROUND

Breath-actuated inhalers (BAIs) eliminate the need for hand-breath coordination required of pressurized metered-dose inhalers (MDIs). This pharmacokinetic study compared systemic exposure following beclomethasone dipropionate delivery through BAI versus MDI.

METHODS

This open-label, three-period crossover, single-dose study randomized healthy subjects aged 18-45 years (N = 72) to 1 of 6 treatment sequences containing beclomethasone dipropionate BAI 160 mcg (40 mcg/inhalation, 4 inhalations), beclomethasone dipropionate BAI 320 mcg (80 mcg/inhalation, 4 inhalations), and beclomethasone dipropionate MDI 320 mcg (80 mcg/inhalation, 4 inhalations). Blood samples were collected predose through 24 hours postdose for determination of plasma concentrations of beclomethasone-17-monopropionate (17-BMP), the active metabolite of beclomethasone dipropionate. The primary pharmacokinetic parameters were area under the plasma drug concentration-time curve (AUC) from time 0 (predose) until the last measurable drug concentration (AUC_0-t) and maximum plasma drug concentration (C_max) for 17-BMP. Safety was assessed by adverse events, vital signs, clinical laboratory tests, and physical examinations.

RESULTS

Plasma concentrations of 17-BMP peaked at a median of 10 minutes after the last inhalation of all study treatments and remained measurable for at least 18 hours in most subjects. Mean elimination half-life was ∼4 hours. The AUC_0-t and C_max for 17-BMP were 11% and 14% higher, respectively, when beclomethasone dipropionate 320 mcg was administered through BAI versus MDI, but the 90% confidence intervals of the geometric least squares mean BAI:MDI ratio for each parameter were fully contained within the bioequivalence boundaries of 0.80-1.25. Plasma concentrations of 17-BMP following beclomethasone dipropionate 160 mcg BAI were approximately half those with 320 mcg through BAI or MDI. All treatments were safe and generally well tolerated.

CONCLUSIONS

Systemic availability of 17-BMP following administration of beclomethasone dipropionate was bioequivalent between BAI and MDI at the 320-mcg dose, and approximately dose proportional at the 160- and 320-mcg doses using the BAI.

Salmeterol/fluticasone through breath-actuated inhaler versus pMDI: a randomized, double-blind, 12 weeks study

OBJECTIVE

Salmeterol/fluticasone combination (SFC) formulated in a breath-actuated inhaler (BAI) overcomes the co-ordination problem associated with the pressurized-metered dose inhaler (pMDIs). Our aim was to compare the efficacy and the safety of SFC given through the BAI versus the conventional pMDI in moderate-to-severe asthmatics.

METHODS

In this randomized, double-blind, double-dummy, prospective, active-controlled, parallel group, multicenter, 12 weeks study, 150 asthmatics were randomized to receive SFC (25/125 mcg) through either BAI or pMDI. The primary efficacy endpoint was mean change in pre-dose morning PEFR value at 12 weeks and the secondary efficacy endpoints included, mean change in FEV(1), pre-bronchodilator FVC, pre-dose morning and evening PEFR, symptom scores at 2, 4, 8, and 12 weeks. Patient preferences for device and safety were also assessed.

RESULTS

At 12 weeks, the mean change in pre-dose morning PEFR in BAI and pMDI groups was 50.72 L/min and 48.82 L/min, respectively (p < 0.0001; both groups) and the difference between the two groups was not significant. Both the treatment groups showed a statistically significant improvement in secondary endpoints at all-time points compared with baseline. The usability questionnaire assessment results showed that the BAI device was preferred by 75% of patients as compared with 25% preferring pMDI. SFC in both BAI and pMDI devices was found to be safe and well tolerated.

CONCLUSION

This is the first study to demonstrate that SFC given through the BAI produces comparable efficacy and safety endpoints as pMDI. Additionally, BAI was the preferred inhaler by patients compared to conventional pMDI.

Effectiveness of same versus mixed asthma inhaler devices: a retrospective observational study in primary care

PURPOSE

Correct use of inhaler devices is fundamental to effective asthma management but represents an important challenge for patients. The correct inhalation manoeuvre differs markedly for different inhaler types. The objective of this study was to compare outcomes for patients prescribed the same inhaler device versus mixed device types for asthma controller and reliever therapy.

METHODS

This retrospective observational study identified patients with asthma (ages 4-80 years) in a large primary care database who were prescribed an inhaled corticosteroid (ICS) for the first time. We compared outcomes for patients prescribed the same breath-actuated inhaler (BAI) for ICS controller and salbutamol reliever versus mixed devices (BAI for controller and pressurised metered-dose inhaler [pMDI] for reliever). The 2-year study included 1 baseline year before the ICS prescription (to identify and correct for confounding factors) and 1 outcome year. Endpoints were asthma control (defined as no hospital attendance for asthma, oral corticosteroids, or antibiotics for lower respiratory tract infection) and severe exacerbations (hospitalisation or oral corticosteroids for asthma).

RESULTS

Patients prescribed the same device (n=3,428) were significantly more likely to achieve asthma control (adjusted odds ratio, 1.15; 95% confidence interval [CI], 1.02-1.28) and recorded significantly lower severe exacerbation rates (adjusted rate ratio, 0.79; 95% CI, 0.68-0.93) than those prescribed mixed devices (n=5,452).

CONCLUSIONS

These findings suggest that, when possible, the same device should be prescribed for both ICS and reliever therapy when patients are initiating ICS.

Effectiveness of inhaler types for real-world asthma management: retrospective observational study using the GPRD

PURPOSE

Results of randomized controlled trials may not predict effectiveness of inhaled corticosteroids (ICS) in real-world clinical practice, where inhaler technique and device characteristics can influence effectiveness. We compared asthma outcomes for ICS delivered via three different inhaler devices: pressurized metered-dose inhaler (pMDI), breath-actuated MDI (BAI), and dry powder inhaler (DPI).

PATIENTS AND METHODS

This retrospective database study evaluated 1-year outcomes for primary care patients with asthma aged 5-60 years prescribed their first ICS (initiation population) by pMDI (n = 39,746), BAI (n = 9809), or DPI (n = 6792), or their first ICS dose increase (step-up population) by pMDI (n = 6245), BAI (n = 1388), or DPI (n = 1536). Co-primary outcome measures were composite proxy measures of asthma control (no hospital attendance for asthma, oral corticosteroids, or antibiotics for lower respiratory infection) and severe exacerbations (unscheduled hospital admission, emergency room attendance, or oral corticosteroids). Outcomes were adjusted for potential confounding factors identified during a baseline year.

RESULTS

In the initiation population, adjusted odds ratios (95% confidence intervals [CI]) for asthma control, as compared with pMDIs, were significantly better for BAIs (1.08 [1.02-1.14]) and DPIs (1.13 [1.06-1.21]), while adjusted exacerbation rate ratios (95% CI) were 1.00 (0.93-1.08) and 0.88 (0.81-0.95), respectively. In the step-up population, adjusted odds of asthma control were 1.21 (1.05-1.39) for BAIs and 1.13 (0.99-1.29) for DPIs; adjusted exacerbation rate ratios were 0.83 (0.71-0.98) for BAIs and 0.85 (0.74-0.98) for DPIs, compared with pMDIs.

CONCLUSION

Inhaler device selection may have a bearing on clinical outcomes. Differences in real-world effectiveness among these devices require closer evaluation in well-designed prospective trials.

Cost-effectiveness analysis of corticosteroid inhaler devices in primary care asthma management: A real world observational study

PURPOSE

To evaluate and compare real world cost-effectiveness of inhaled corticosteroids (ICS) administered by metered dose inhaler (MDI), breath-actuated MDI (BAI), or dry powder inhaler (DPI) in asthma.

PATIENTS AND METHODS

This retrospective database study analyzed the direct health care costs and proportion of patients (aged 5-60 years) achieving asthma control over 1 year in two population groups: those starting ICS (initiation population) and those receiving a first increase in ICS dose (step-up population). Asthma control was defined as no unplanned asthma visits, oral corticosteroids, or antibiotics for lower respiratory infection; outcomes were adjusted for confounding variables. Cost-effectiveness of BAI and DPI were compared with MDI.

RESULTS

For the initiation population (n = 56,347), average annual health care costs per person (adjusted results), as compared with MDIs, were £9 higher (95% CI: -1.65 to 19.71) for BAIs and £32 higher (95% CI: 19.51 to 43.66) for DPIs. The probability of BAIs being the dominant strategy (more effective and less costly than MDIs) was 5% and of BAIs being more effective and more costly than MDIs was 94%. DPIs were consistently more effective and more costly than MDIs, with an incremental cost-effectiveness ratio of £1711 (95% CI: 760 to 3,576) per additional controlled patient per year. For the step-up population (n = 9169), mean total health care costs per person, (adjusted) as compared with MDIs, were £1 higher (95% CI: -27.28 to 31.55) for BAIs and £73 higher (95% CI: 44.48 to 103.29) for DPIs. The probability of BAIs being dominant was 48% and of BAIs being more effective but more costly than MDIs was 52%; the probability of DPIs being more effective but more costly than MDIs was 96%.

CONCLUSION

The real world effectiveness of ICS inhalers may vary, and inhaler device selection for patients with asthma should take into consideration not only initial device cost but also the subsequent health care resource costs.