Tiotropium bromide: an update

Future perspectives of anticholinergics for the treatment of asthma in adults and children

Despite major advances in therapeutic interventions and the availability of detailed treatment guidelines, a high proportion of patients with symptomatic asthma remain uncontrolled. Asthma management is largely guided by the Global Initiative for Asthma (GINA) strategy and is based on a backbone of inhaled corticosteroid (ICS) therapy with the use of additional therapies to achieve disease control. Inhaled long-acting bronchodilators alone and in combination are the preferred add-on treatment options. Although long-acting muscarinic antagonists (LAMAs) are a relatively recent addition to disease management recommendations for asthma, tiotropium has been extensively studied in a large clinical trial program. In Europe and the United States, tiotropium is approved for patients aged ≥6 years and uncontrolled on medium- to high-dose ICS/long-acting β2-agonists at GINA Steps 4 and 5 with a history of exacerbations. Evidence supports the efficacy of tiotropium Respimat® in adults in terms of lung function and asthma control, with a safety profile comparable with that of placebo across a range of asthma severities. Similarly, clinical trials in patients aged 1-17 years have shown improvements in lung function and trends toward improved asthma control. Furthermore, its efficacy makes tiotropium relatively easy to incorporate into routine clinical practice, irrespective of allergic status and without the need for patient phenotyping. Tiotropium is a cost-effective treatment that may offer an important alternative to other, more expensive add-on therapies. This review discusses the potential future position of LAMAs in clinical practice by considering the continuously evolving evidence. Prominence is given to tiotropium, the only LAMA supported by a structured clinical trial program in asthma to date, while also considering other recommended treatment options for patients with uncontrolled asthma. The importance of effective patient/caregiver-clinician communication and shared decision-making in enhancing treatment adherence is also highlighted.

Bronchodilator Effect of Tiotropium via Respimat®Administered with a Spacer in Patients with Chronic Obstructive Pulmonary Disease (COPD)

Objective Among elderly patients with chronic obstructive pulmonary disease (COPD), there are some patients who cannot inhale tiotropium via Respimat^® due to poor hand-lung coordination. This study aimed to examine whether or not tiotropium inhalation therapy using Respimat^® with a spacer increased the forced expiratory volume in 1 s (FEV₁) in patients with COPD. Methods A randomized, crossover, single-center study was conducted in 18 patients with stable COPD. Tiotropium (5 μg) via Respimat^® with or without a spacer (AeroChamber^®) was administered for 2 weeks. Following a 2-week washout period using a transdermal tulobuterol patch (2 mg per day), participants were then crossed over to the other inhalation therapy with respect to spacer use. The trough FEV₁ was measured at every visit using a spirometer. A questionnaire regarding inhalation therapy was administered to patients at the final visit. Results The administration of tiotropium via Respimat^® both with and without a spacer significantly increased the trough FEV₁ from baseline during each treatment period, with mean differences of 115.0±169.6 mL and 92.8±128.1 mL, respectively. There was no significant difference in the change in the trough FEV₁ between the 2 procedures (p=0.66). A total of 86% of patients reported that inhalation using a spacer was not difficult, and more than half also rated both the usage and maintenance of the AeroChamber^® as easy. Conclusion Tiotropium inhalation therapy administered via Respimat^® using a spacer exerted a bronchodilatory effect similar to that observed with tiotropium Respimat^® alone.

Effect of inhaled drugs on anxiety and depression in patients with chronic obstructive pulmonary disease: a prospective observational study

Objective

We investigated the effect of treatment with inhaled drugs on changes in mood, focusing on depression and anxiety during treatment in patients with newly diagnosed chronic obstructive pulmonary disease (COPD).

Methods

We prospectively selected new COPD patients from three Seoul National Hospitals. Participants underwent face-to-face interviews to evaluate clinical characteristics and drug use, and completed questionnaires using the Hospital Anxiety and Depression Scale (HADS) at the start of the project, the 4th week, and the 12th week. We compared changes in HADS scores both between inhaled corticosteroid (ICS)/long-acting β₂ agonist (LABA) users and non-ICS/LABA users, as well as between long-acting muscarinic antagonist (LAMA) users and non-LAMA users. The general linear mixed model was applied for multivariate analysis.

Results

Ninety new COPD patients participated in the study. Of these 90 patients, 84 completed face-to-face interviews. In the univariate analysis, those who were treated by ICS/LABA or LAMA showed a significant increase in HADS-A at the 4-week evaluation (0.73±2.56, P=0.038), but the statistical significance was lost in the multivariable analysis. No significant difference was found in the change in HADS scores between ICS/LABA users and non-ICS/LABA users, or between LAMA users and non-LAMA users in multivariate general linear mixed model analyses.

Conclusion

In this prospective observational study, we found no significant effects of inhaled treatment on mood problems among new COPD patients. Further research should be conducted to identify the association between anxiety and depression and inhaled drugs for COPD treatment.

Comparative characterization of lung muscarinic receptor binding after intratracheal administration of tiotropium, ipratropium, and glycopyrrolate

The aim of the current study was to characterize comparatively the binding of muscarinic receptor in the lung of rats intratracheally administered anticholinergic agents (tiotropium, ipratropium, glycopyrrolate) used clinically to treat chronic obstructive pulmonary disease (COPD) and asthma. Binding parameters of [N-methyl-(3)H]scopolamine methyl chloride ([(3)H]NMS) were determined in tissues (lung, bladder, submaxillary gland) of rats intratracheally administered tiotropium, ipratropium, and glycopyrrolate. The in vitro binding affinity of tiotropium for the receptors was 10-11-fold higher than those of ipratropium and glycopyrrolate. Intratracheal administration of tiotropium (0.6-6.4 nmol/kg) caused sustained (lasting at least 24 h) increase in the apparent dissociation constant (K(d)) for [(3)H]NMS binding in rat lung compared with the control value. Concomitantly, there was a long-lasting decrease in the maximal number of binding sites (B(max)) for [(3)H]NMS. Similary, ipratropium and glycopyrrolate at 7.3 and 7.5 nmol/kg, respectively, brought about a significant increase in K(d) for [(3)H]NMS binding. The effect by ipratropium was observed at 2 h but not 12 h, and that by glycopyrrolate lasted for 24 h. Both agents had little influence on the muscarinic receptors in the bladder and submaxillary gland. The present study provides the first evidence that tiotropium, ipratropium, and glycopyrrolate administered intratracheally in rats selectively bound muscarinic receptors of the lung, and tiotropium and glycopyrrolate had a much longer-lasting effect than ipratropium.

Transport of ipratropium, an anti-chronic obstructive pulmonary disease drug, is mediated by organic cation/carnitine transporters in human bronchial epithelial cells: implications for carrier-mediated pulmonary absorption

Ipratropium bromide, an anticholinergic drug used for the treatment of asthma and chronic obstructive pulmonary disease, has low oral bioavailability, but systemic exposure, superior to oral administration, can be achieved by inhalation. Therefore, we investigated the pulmonary absorption mechanism of ipratropium using human bronchial epithelial BEAS-2B cells. [3H]Ipratropium uptake by BEAS-2B cells was temperature-dependent and saturable, with a K(m) value of 78.0 microM, suggesting involvement of carrier-mediated uptake. An RT-PCR study showed that organic cation/carnitine transporters OCTN1 and OCTN2 are expressed in BEAS-2B cells, but organic cation transporters (OCTs) are not. Uptake of [3H]ipratropium by HEK293 cells expressing OCTN1 (HEK293/OCTN1) and OCTN2 (HEK293/OCTN2) was significantly increased, compared with mock-transfected cells, and the estimated K(m) values were 444 microM and 53.0 microM, respectively. Finally, the contributions of OCTN1 and OCTN2 to ipratropium uptake were evaluated by measuring [3H]ipratropium uptake by BEAS-2B cells in which OCTN1 or OCTN2 gene expression had been silenced. Knock-down of OCTN1 or OCTN2 suppressed the uptake of [3H]ipratropium to 78.2% and 14.8% of that by control BEAS-2B cells, respectively. In addition, another anticholinergic, tiotropium, was also taken up by both HEK293/OCTN1 and HEK293/OCTN2 cells. Therefore, ipratropium and tiotropium are taken up primarily by OCTN2, and to a lesser extent by OCTN1, in bronchial epithelial cells. These findings are consistent with the pharmacological activity of the drugs after administration via inhalation.