Ipratropium and lung health study

The safety of anticholinergic bronchodilators for the treatment of chronic obstructive pulmonary disease

INTRODUCTION

Poorly absorbable quaternary ammonium-inhaled muscarinic antagonists both as the short-acting ipratropium and as long-acting (12 - 24 h) agents (tiotropium, glycopyrronium, aclidinium and umeclidinium) have all demonstrated statistically and clinically significant efficacy in chronic obstructive pulmonary disease compared with placebo. However, controversy has arisen concerning the safety of this class of agents principally regarding their association with both fatal and nonfatal cardiovascular toxicity.

AREAS COVERED

The safety of both ipratropium and the long-acting muscarinic antagonists is reviewed with a major emphasis on potential cardiovascular toxicity, based on published clinical trials data and results of analyses of pooled data, meta-analyses, and observational studies. Since glycopyrronium, aclidinium, and umeclidinium have become available only relatively recently, more emphasis will be placed on the more extensive literature concerning the safety of the older anticholinergic compounds, the short-acting ipratropium, and the long-acting tiotropium in its dry powder formulation, as well as its newer soft mist inhaler delivery device.

EXPERT OPINION

Pooled analyses and meta-analyses of randomized controlled trials (RCTs) of tiotropium in both its dry powder and soft mist formulations, as well as some observational studies, have implicated this agent as increasing the risk of nonfatal and fatal cardiovascular events. However, the most robust evidence based on large-scale randomized controlled trials (RCTs) of relatively long duration specifically designed to evaluate the cardiovascular safety of tiotropium have not confirmed these safety concerns. Because of the relatively limited amount of safety data for the newer long-acting muscarinic antagonists compared to the far more extensive experience with tiotropium, it will be important to accumulate additional safety information from post-marketing pharmacovigilance for these newer agents.

Risks associated with tiotropium in chronic obstructive pulmonary disease: overview of the evidence to date

Tiotropium is a long-acting inhaled anticholinergic agent that is widely used in the treatment of chronic obstructive pulmonary disease (COPD). It was initially launched as the tiotropium HandiHaler formulation, but this was followed by a newer version based on a potentially more efficient drug delivery device, known as Respimat. This Respimat formulation is available worldwide but has not yet succeeded in gaining regulatory approval in the USA. In the past few years, the adverse effects profile of tiotropium has come under close scrutiny owing to concerns about the possibility of urinary and cardiovascular adverse effects. These concerns appeared to have been alleviated following the publication of data from the Understanding Potential Long-Term Impacts on Function with Tiotropium (UPLIFT) trial, which was a large trial of 4 years' duration. This trial did not show any excess myocardial infarction, renal or urinary adverse events with tiotropium compared with placebo. However, the risk of urinary retention has been in the spotlight again following publication of two observational studies reporting a significantly increased risk of urinary retention in men recently started on inhaled anticholinergics, especially when prostatic hyperplasia coexists. More recently, a meta-analysis of mortality data for the tiotropium Respimat formulation raised the possibility of an increased risk of death, including death from cardiovascular causes. It is unclear if the more efficient drug delivery offered by the Respimat device is hitting a different part of the dose-toxicity curve. In the absence of any evidence of superior clinical efficacy with tiotropium Respimat compared with tiotropium HandiHaler, some experts have argued that there is no compelling reason to choose the Respimat formulation given the new uncertainties about its safety profile.

Evaluating the safety of COPD medications: an evidence-based review

The goals of management of COPD include reducing exposure to risk factors; improving lung function, exercise tolerance, and quality of life; and decreasing exacerbations and mortality. Pharmacologic treatments, such as inhaled β2-agonists, anticholinergics, and inhaled corticosteroids, are widely used to help achieve these goals. In addition to efficacy, medication safety is an important consideration in selecting COPD treatments. Clinical trials conducted in support of the regulatory review and approval process establish the general efficacy and tolerability of pharmacologic treatments for COPD, and these data are reflected in product labeling. Following approval, further research continues to provide more data with longer follow-up and in broader settings than feasible in clinical trials. These data add to our knowledge of the efficacy of medications. Understanding medication safety requires assessment of the quality and appropriateness of study design, as well as knowledge of study findings, and is of paramount importance in making sound clinical judgments in the treatment of patients with COPD. In recent years, a wealth of data on COPD medications has been published from different sources, including randomized clinical trials, meta-analyses, systematic reviews, and observational studies. This review discusses important considerations in interpreting data from different types of studies, summarizes the tolerability profile of COPD medications established in preapproval studies, and discusses new findings from more recent postapproval data.

Tiotropium bromide for chronic obstructive pulmonary disease

Tiotropium bromide is a long-acting, once-daily inhaled anticholinergic approved for the treatment of chronic obstructive pulmonary disease (COPD). Functional and kinetic selectivity for muscarinic (M) receptors, M(1) and M(3), in the lung permit sustained bronchodilation in moderate and severe COPD. Tiotropium is associated with increased lung function, health-related quality of life and exercise tolerance, and reduced dyspnea and acute exacerbations of COPD. It has been hypothesized that tiotropium may retard the accelerated decline in lung function associated with COPD, although a recent study does not support this notion. Tiotropium is safe and well-tolerated, with few side effects. Concerns about cardiovascular side effects and increased stroke risk have been alleviated by a recent, large, multicenter, prospective, randomized trial. Herein, we discuss the pharmacology, physiology and safety profile of tiotropium, as well as the clinical studies that have demonstrated its efficacy in COPD. Additional review of airway muscarinic receptor physiology and cholinergic pathobiology relevant to COPD and asthma provides context for future experimental and therapeutic roles for tiotropium.

Tiotropium bromide inhalation powder: a review of its use in the management of chronic obstructive pulmonary disease

The anticholinergic agent tiotropium bromide (Spiriva®) is a long-acting bronchodilator that is indicated for the treatment of chronic obstructive pulmonary disease (COPD). This article reviews the clinical efficacy and tolerability of tiotropium bromide inhalation powder, administered using the HandiHaler® device, in patients with COPD, as well as reviewing its pharmacological properties and the results of pharmacoeconomic analyses. Shorter-term placebo-controlled trials in patients with COPD demonstrated significantly higher trough forced expiratory volume in 1 second (FEV(1)) responses with tiotropium bromide than with placebo, confirming it has a duration of action of ≥24 hours and is suitable for once-daily administration. Lung function improved to a greater extent with tiotropium bromide than with ipratropium bromide or, in most instances, salmeterol. Indacaterol was shown to be noninferior to tiotropium bromide in terms of the trough FEV(1) response. The large, 4-year UPLIFT® trial did not show a significant reduction in the annual rate of decline in FEV(1) with tiotropium bromide versus placebo in patients with COPD, although subgroup analyses demonstrated a significantly lower rate of decline with tiotropium bromide than with placebo in some patient groups (e.g. patients with moderate COPD, patients aged ≥50 years, patients not receiving maintenance therapy at baseline). Tiotropium bromide prevented exacerbations in patients with COPD, with a significantly lower exacerbation rate and a significantly longer time to first exacerbation seen with tiotropium bromide than with placebo or salmeterol. Exacerbation rates did not significantly differ between patients receiving tiotropium bromide and those receiving salmeterol/fluticasone propionate. Tiotropium bromide also had beneficial effects on health-related quality of life (HR-QOL) and other endpoints, such as dyspnoea and rescue medication use. Combination therapy with tiotropium bromide plus formoterol with or without budesonide improved lung function to a significantly greater extent than tiotropium bromide alone in patients with COPD. In addition, exacerbation rates were lower and HR-QOL was improved with tiotropium bromide plus budesonide/formoterol versus tiotropium bromide alone. Although the addition of salmeterol/fluticasone propionate to tiotropium bromide did not reduce the COPD exacerbation rate, it did improve lung function and HR-QOL. Tiotropium bromide inhalation powder is generally well tolerated in patients with COPD, with anticholinergic adverse events (e.g. dry mouth, constipation, gastrointestinal obstruction, dysuria) among the most commonly reported adverse events. The UPLIFT® trial showed no significant difference between tiotropium bromide and placebo recipients in the risk of stroke, and the risk of serious cardiac adverse events (including congestive heart failure and myocardial infarction) was significantly lower with tiotropium bromide than with placebo. The absence of a detrimental effect on cardiovascular outcomes was supported by the results of a meta-analysis and pooled analyses. In addition, on-treatment mortality was lower with tiotropium bromide than with placebo in the UPLIFT® trial. Pooled analyses showed significantly lower cardiovascular mortality with tiotropium bromide than with placebo, with a meta-analysis demonstrating no significant difference between patients receiving tiotropium bromide and controls in cardiovascular mortality. Results of modelled pharmacoeconomic analyses conducted from a healthcare payer perspective in several developed countries suggest that tiotropium bromide is a cost-effective option in patients with COPD. In conclusion, tiotropium bromide inhalation powder is a useful option for the maintenance treatment of patients with COPD.

Safety of chronic obstructive pulmonary disease medications: a primary care perspective

Chronic obstructive pulmonary disease (COPD), which affects > 210 million individuals worldwide, places primary care practitioners at the forefront of diagnosing and managing COPD, and preventing adverse drug reactions (ADRs) associated with COPD medications. Therefore, it is essential that practitioners understand the safety profiles of these medications. They should also be aware of the host factors and any preexisting comorbidities in their patients that may impact the safety and efficacy of the prescribed therapy. Drug safety information obtained from randomized controlled trials, observational studies, and meta-analyses should be analyzed to assess the risk-benefit to a patient, since the majority of ADRs associated with COPD medications are predictable, and are avoidable with judicious use of these drugs. This article discusses the different medications available for COPD management and the factors affecting their safety based on current evidence.

Do inhaled anticholinergics increase or decrease the risk of major cardiovascular events?: a synthesis of the available evidence

There has been recent uncertainty about whether the inhaled anticholinergic agents ipratropium bromide and tiotropium bromide increase or decrease cardiovascular risk in the treatment of patients with chronic obstructive pulmonary disease (COPD). This article synthesizes the available data in order to understand the controversy. COPD is a common cause of hospitalizations and is a rapidly increasing cause of mortality worldwide. Despite the heavy burden of COPD-related illness, the leading cause of hospitalization in COPD patients is cardiovascular disease. This link between COPD and cardiovascular disease is in part due to the fact that both diseases share common risk factors, such as tobacco smoking and advanced age. It is also hypothesized that systemic inflammation in COPD increases the risk for cardiac events such as myocardial infarction. Inhaled anticholinergics reduce COPD-related hospitalizations and respiratory deaths compared with placebo, and tiotropium bromide is more effective than ipratropium bromide. In randomized trials, patients receiving tiotropium bromide have lower discontinuation rates than those receiving placebo and, therefore, contribute more person-years to the analyses. In a recent large 4-year tiotropium bromide trial, the proportion of patients who died was similar in the tiotropium bromide and placebo groups, whereas the death rate per person-years was lower with tiotropium bromide, indicating longer overall survival. There has been conflicting evidence concerning cardiovascular risk associated with inhaled anticholinergics. One meta-analysis found that the risk for major cardiovascular events was higher with anticholinergics compared with placebo or active comparator controls, whereas two subsequent meta-analyses that included new trial data found no difference in risk. In a recent pooled safety analysis, when incidence rates of events over time were evaluated, tiotropium bromide was associated with a lower rate of major cardiovascular events and cardiovascular deaths compared with placebo. This risk reduction was mainly because of a reduction in serious cardiac events such as myocardial infarction and congestive heart failure. In conclusion, inhaled anticholinergics, especially tiotropium bromide, reduce COPD-related hospitalizations and deaths, and may improve total survival over time. Many COPD patients have concomitant cardiovascular disease processes. Thus, trials may observe more cardiovascular events associated with anticholinergics than with placebo, but this differential is eliminated when evaluating the rate of events per person-years of exposure. New evidence indicates that tiotropium bromide may actually reduce the incidence of cardiovascular events and deaths over time. It is possible that the reduction in respiratory morbidity could improve functional status and reduce adverse cardiac outcomes over time. Further studies are needed to address this important issue.

Tiotropium HandiHaler in the treatment of COPD: a safety review

Background

Tiotropium is a long-acting inhaled anticholinergic developed for the treatment of chronic obstructive pulmonary disease (COPD) and has been available since 2002. We sought to update an evaluation of the safety of tiotropium in the HandiHaler^® formulation as significant clinical trial data have become available over time.

Methods

Pooled analysis of adverse event reporting from phase III and IV tiotropium HandiHaler^® clinical trials with the following characteristics was performed: randomized, double-blind, parallel group, placebo-controlled design, tiotropium 18 μg once-daily dosing, COPD indication, duration of at least four weeks. Incidence rates by treatment group, rate differences (tiotropium–placebo), and 95% confidence intervals were determined.

Results

Twenty-six trials were identified involving 17,014 patients. Mean age was 65 years, mean forced expiratory volume in one second was 1.16 L (41% predicted), 76% men. Total exposure to study drug was 11,958 patient-years (tiotropium) and 10,578 patient-years (placebo). Tiotropium was associated with a reduced risk (expressed as rate difference [95% confidence interval] per 100 patients-years at risk) for an adverse event (−17.5 [−22.9, −12.2]), serious adverse event (−1.41 [−2.81, −0.00]) and a fatal event (−0.63 [−1.14, −0.12]). A reduced risk was present for adverse events that were cardiac (−0.79 [−1.48, −0.09]), lower respiratory (−14.2 [−17.0, −11.5]) and for a composite endpoint of major adverse cardiovascular events (−0.45 [−0.85, −0.05]). Typical expected inhaled anticholinergic effects such as dry mouth, constipation, and urinary difficulties were observed in the safety database.

Conclusion

The safety data review does not indicate an increased risk for death or cardiovascular morbidity during tiotropium treatment in patients with COPD.

Pooled clinical trial analysis of tiotropium safety

BACKGROUND

Marketing approval of pharmaceutical products is often based on data from several thousand subjects or fewer. Evaluation of safety is greatly enhanced by augmenting the safety database with postapproval studies.

METHODS

We conducted a pooled analysis of adverse event data from 19 randomized, double-blind, placebo-controlled trials with tiotropium in patients with obstructive lung disease. We computed incidence rates and rate ratios (RRs) for various reported adverse event end points of interest. Patients contributed person-time to the analysis as long as they were in the study until 30 days after treatment (tiotropium, placebo), or until they had the event of interest, whichever came first. Studies were pooled using the Mantel-Haenszel estimator, and we used 95% confidence intervals (CIs) to assess the precision of effect estimates.

RESULTS

The pooled trial population includes 4,435 tiotropium patients and 3,384 placebo patients contributing 2,159 person-years of exposure to tiotropium and 1,662 person-years of exposure to placebo. Dyspnea, dry mouth, COPD exacerbation, and upper respiratory tract infection were the most commonly reported events. There was a higher relative risk of dry mouth in the tiotropium group (RR, 3.60; 95% CI, 2.56 to 5.05). There was a lower risk of dyspnea (RR, 0.64; 95% CI, 0.50 to 0.81) and COPD exacerbation (RR, 0.72; 95% CI, 0.64 to 0.82) in patients receiving tiotropium compared to patients receiving placebo. Other results of interest are as follows: (1) all-cause mortality (RR, 0.76; 95% CI, 0.50 to 1.16); (2) cardiovascular mortality (RR, 0.57; 95% CI, 0.26 to 1.26); and (3) respiratory mortality (RR, 0.71; 95% CI, 0.29 to 1.74). The relative risk of urinary retention was 10.93 (95% CI, 1.26 to 94.88).

CONCLUSIONS

Pooling of adverse event data from preapproval and postapproval tiotropium clinical trials increase the precision of effect estimates and supports the present safety profile of tiotropium.

Absence of electrocardiographic findings and improved function with once-daily tiotropium in patients with chronic obstructive pulmonary disease

STUDY OBJECTIVES

To examine electrocardiographic findings after short- and long-term tiotropium therapy in patients with chronic obstructive pulmonary disease (COPD), and to establish previously reported symptomatic efficacy.

DESIGN

Randomized, double-blind, placebo-controlled, parallel-group study.

SETTING

Twelve outpatient investigational centers in the United States.

PATIENTS

One hundred ninety-six patients with COPD.

INTERVENTIONS

Patients received either tiotropium 18 mug once/day or placebo, delivered by the HandiHaler device.

MEASUREMENTS AND MAIN RESULTS

Electrocardiography (predose and 5 min postdose) and 24-hour Holter monitoring were performed at baseline and after 8 and 12 weeks of treatment with tiotropium 18 microg once/day or placebo. Efficacy measures (spirometry, global COPD ratings, scores on the EuroQol Health Questionnaire [EQ-5D], albuterol inhaler as needed) were included to demonstrate that the study population exhibited the characteristic improvements observed in previous tiotropium studies. Mean baseline forced expiratory volume in 1 second (FEV1) was 1.03 L. Mean changes in heart rate from baseline were similar in both groups. No differences were noted in the percentage of patients developing rhythm or conduction abnormalities detected with electrocardiography or Holter monitoring. Frequency of premature beats and mean maximal changes in PR, QRS, QT, QTcB, and QTcF intervals were similar in both groups. No patients developed new-onset QT or QTc intervals greater than 500 msec, and no differences were noted in the percentage of patients developing new QT prolongation less than 30 msec, 30-60 msec, or greater than 60 msec. At 12 weeks, predose and postdose improvements in FEV1 were 184 and 265 ml, respectively, with tiotropium versus placebo (p<0.001). Physician and patient global COPD ratings and the EQ-5D visual analog scale scores were improved with tiotropium (p<0.05); as-needed albuterol was reduced by 25% relative to placebo (p<0.05).

CONCLUSION

Tiotropium provided spirometric and symptomatic benefits in patients with COPD and was not associated with evidence of electrocardiographic changes in heart rate, rhythm, QT intervals, or conduction.

Eletrocardiographic Monitoring in COPD Patients Receiving Tiotropium

Tiotropium is a once-daily, inhaled anticholinergic for the treatment of chronic obstructive pulmonary disease that acts as a prolonged antagonist of the M3-receptor. To ascertain whether electrophysiologic effects can be detected following tiotropium treatment in patients with chronic obstructive pulmonary disease, serial electrocardiograms were incorporated into multiple placebo-controlled clinical trials including long-term (6 and 12-month) trials with tiotropium 18 mcg daily (n=2,128) and a 4-week dose-ranging study with tiotropium up to 36 mcg daily (n= 169). In addition, 24-hour electrocardiographic (Holter) monitoring was performed as part of a 6-week, placebo-controlled trial with tiotropium 18 mcg daily (n= 121). Electrocardiograms were performed before and up to 6 times during treatment in the 12-month trials, and before and at the end of treatment in the 6-month trials. For both the 12 and 6-month trials, electrocardiograms were recorded as adverse events if significant changes occurred, and were retrospectively sent for centralized analysis. During the 6-week trial, Holter monitoring was performed prior to the first dose and following 6 weeks of treatment. In all of these trials, no significant differences were observed in any of the electrocardiogram or Holter outcome parameters compared to placebo. Specifically, there was no clinically relevant difference in heart rate, atrio-ventricular conduction or the occurrence of ventricular or supraventricular arrhythmias. In conclusion, tiotropium was not associated with any signs of cardiac safety concerns as defined by electrocardiographic evaluations in placebo-controlled clinical trials.

Extracellular matrix modulates beta2-adrenergic receptor signaling in human airway smooth muscle cells

The airways of patients with chronic asthma commonly develop an element of fixed airway obstruction, which fails to reverse with inhaled beta2-adrenoceptor agonists. Airway remodeling refers to the structural changes of the bronchi in longstanding asthma and is characterized by increased deposition and altered ratios of extracellular matrix (ECM) proteins. We therefore assessed whether ECM proteins alter beta2-adrenoceptor signaling in human airway smooth muscle cells. We report that a fibronectin environment increases responses to beta2-adrenoceptor stimulation, whereas exposure to collagen V or laminin decreases accumulation of the second messenger cyclic AMP when compared with collagens I or IV. These differences are likely to be physiologically significant as they translate into altered phosphorylation of the downstream target VASP. The altered cAMP levels are due to differences in adenylyl cyclase activity, although expression of the relevant isoforms of enzyme appears unaltered. However, inhibition of Galphai abrogates the differences in beta2-adrenoceptor-mediated cAMP accumulation in cells exposed to different matrix factors. The difference in Galphai signaling is not due to altered Galphai expression. We conclude therefore that ECM modulates Galphai activity in human airway smooth muscle cells, and propose that these changes could contribute to the fixed airway obstruction seen in patients with chronic asthma.