Efficacy and safety of AZD3199 vs formoterol in COPD: a randomized, double-blind study

Ultra Long-Acting β-Agonists in Chronic Obstructive Pulmonary Disease

INTRODUCTION

Inhaled β-agonists have been foundational medications for maintenance COPD management for decades. Through activation of cyclic adenosine monophosphate pathways, these agents relax airway smooth muscle and improve expiratory airflow by relieving bronchospasm and alleviating air trapping and dynamic hyperinflation improving breathlessness, exertional capabilities, and quality of life. β-agonist drug development has discovered drugs with increasing longer durations of action: short acting (SABA) (4-6 h), long acting (LABA) (6-12 h), and ultra-long acting (ULABA) (24 h). Three ULABAs, indacaterol, olodaterol, and vilanterol, are approved for clinical treatment of COPD.

PURPOSE

This article reviews both clinically approved ULABAs and ULABAs in development.

CONCLUSION

Indacaterol and olodaterol were originally approved for clinical use as monotherapies for COPD. Vilanterol is the first ULABA to be approved only in combination with other respiratory medications. Although there are many other ULABA's in various stages of development, most clinical testing of these novel agents is suspended or proceeding slowly. The three approved ULABAs are being combined with antimuscarinic agents and corticosteroids as dual and triple agent treatments that are being tested for clinical use and efficacy. Increasingly, these clinical trials are using specific COPD clinical characteristics to define study populations and to begin to develop therapies that are trait-specific.

Investigational beta-2 adrenergic agonists for the treatment of chronic obstructive pulmonary disease

INTRODUCTION

Long-acting bronchodilators are pivotal in the therapeutic management of COPD patients with moderate-to-severe airflow obstruction. New ultra-long-acting β2-agnoists (ultra-LABAs) have been developed, some of which have been licensed for use as monotherapy and/or in combination with other bronchodilators or inhaled corticosteroids, for use in COPD patients with persistent symptoms and worsening airflow limitation. These new agents are faster in onset and have a prolonged duration of action, with a similar safety profile to the traditional twice-daily bronchodilators which may have an impact on patient concordance. Areas covered: A number of these ultra-LABAs are still under development and bi-functional hybrid molecules containing regions functioning as β2-agonists, and as muscarinic agonists (MABAs) has been developed. This review summarizes these (excluding the licensed ultra-LABAs) with attention on phase II studies data available to-date on their pharmacological profiles, clinical efficacy and safety, and future perspectives. Expert opinion: Despite all the new agents' available, the challenges that persist include any differences in efficacy and safety between the various possible LAMA/LABA combinations, relative advantages of MABAs over fixed-dose LAMA/LABAs, and the impact of these new molecules in terms of long term safety, especially in certain populations in co-morbidities frequently associated with COPD.

Health Status of Patients with Moderate to Severe COPD after Treatment with Nebulized Arformoterol Tartrate or Placebo for 1 Year

PURPOSE

Chronic obstructive pulmonary disease (COPD) is a progressive disease that impairs both objectively measured lung function and patient-reported health status. In a randomized clinical trial of patients with moderate to severe COPD, we compared changes in health status after adding arformoterol tartrate or placebo to patients' treatment regimens.

METHODS

In this multicenter, double-blind trial, patients were randomized to receive nebulized arformoterol 15 µg BID (n = 420) or matched placebo (n = 421). Treatment with other COPD medications was permitted, except for long-acting β₂-agonists. Inclusion criteria were a forced expiratory volume in 1 second (FEV₁) ≤65% of predicted, FEV₁ >0.50 L, age ≥40 years, smoking history ≥15 pack-years, and a baseline breathlessness severity grade ≥2. The Clinical COPD Questionnaire (CCQ) was used to measure health status at randomization and at months 3, 6, and 12. CCQ scores range from 0 to 6, with higher scores indicating worse health status, and a decrease from baseline in total score by 0.4 point is considered clinically significant. Outcomes were analyzed by using mixed models for repeated measures.

FINDINGS

At baseline, patients' mean age was 63.8 years; 42.9% of patients were female, and 51.4% were current smokers. The mean baseline CCQ total scores were 2.88 and 2.91 for the arformoterol and placebo groups, respectively. A total of 841 patients were randomized to receive either arformoterol (n = 420) or placebo (n = 421); among them, 211 (50.1%) who received placebo and 255 (60.7%) who received arformoterol completed the trial. Arformoterol-treated patients had greater mean improvement from baseline in CCQ total score (-0.18 vs 0.02; P = 0.001), symptoms (-0.21 vs 0.01; P = 0.002), functional state (-0.15 vs 0.02; P = 0.018), and mental state (-0.18 vs 0.02; P = 0.023) than patients receiving placebo. At study end, 38.3% of the arformoterol-treated patients and 30.8% of patients receiving placebo reported clinically significant improvements on the CCQ (P = 0.026). These improvements were only modestly correlated with improvements in FEV₁ (r = -0.15; P < 0.01).

IMPLICATIONS

In this 52-week trial, arformoterol-treated patients had greater improvements in health status than patients receiving placebo. Assessing health status along with lung function seems to provide additional information regarding the effectiveness of COPD maintenance treatments. ClinicalTrials.gov identifier: NCT00909779.

Clinical pharmacokinetics of AZD3199, an inhaled ultra-long-acting β2-adrenoreceptor agonist (uLABA)

Objective

The clinical pharmacokinetics of AZD3199, an ultra-long-acting β₂-agonist, were investigated in healthy volunteers and patients with asthma or chronic obstructive pulmonary disease (COPD).

Materials and methods

Five studies are presented: one single ascending dose study in healthy Caucasian males; two multiple ascending dose studies in healthy males, one in Caucasians and one in Japanese; a Phase IIA asthma study; and a Phase IIB COPD study. Subjects received AZD3199 via a Spira nebulizer (Turbuhaler; equivalent delivered doses 5–3200 μg) or Turbuhaler (single delivered doses of 120–1920 μg or repeated delivered once-daily doses 240–1,680 μg). AZD3199 pharmacokinetics were assessed using total plasma concentration and urinary excretion, and tolerability using adverse events, clinical laboratory tests, and physical examinations.

Results

AZD3199 appeared rapidly in the systemic circulation following single and multiple dosing in healthy volunteers and patients (maximum plasma concentration within 30 minutes), with dose-proportional time-independent pharmacokinetics. Plasma exposure to unmetabolized drug was similar in healthy volunteers and patients with asthma, but relatively lower in patients with COPD. Estimated terminal half-life was up to 142 hours in healthy Caucasian males. AZD3199 was well tolerated and showed no or at most mild systemic effects.

Conclusion

AZD3199 plasma exposure in healthy volunteers and patients suggested linear pharmacokinetics and a long half-life. Systemic availability was similar in healthy subjects and patients with asthma, but was lower in patients with COPD. These clinical trials suggest that AZD3199 is well-tolerated in healthy male volunteers and patients, with no safety concerns identified to preclude further evaluation.

Prediction of disease progression, treatment response and dropout in chronic obstructive pulmonary disease (COPD)

Purpose

Drug development in chronic obstructive pulmonary disease (COPD) has been characterised by unacceptably high failure rates. In addition to the poor sensitivity in forced expiratory volume in one second (FEV₁), numerous causes are known to contribute to this phenomenon, which can be clustered into drug-, disease- and design-related factors. Here we present a model-based approach to describe disease progression, treatment response and dropout in clinical trials with COPD patients.

Methods

Data from six phase II trials lasting up to 6 months were used. Disease progression (trough FEV₁ measurements) was modelled by a time–varying function, whilst the treatment effect was described by an indirect response model. A time-to-event model was used for dropout

Results

All relevant parameters were characterised with acceptable precision. Two parameters were necessary to model the dropout patterns, which was found to be partly linked to the treatment failure. Disease severity at baseline, previous use of corticosteroids, gender and height were significant covariates on disease baseline whereas disease severity and reversibility to salbutamol/salmeterol were significant covariates on E_max for salmeterol active arm.

Conclusion

Incorporation of the various interacting factors into a single model will offer the basis for patient enrichment and improved dose rationale in COPD.

Electronic supplementary material

The online version of this article (doi:10.1007/s11095-014-1490-4) contains supplementary material, which is available to authorized users.

Update on ultra-long-acting β agonists in chronic obstructive pulmonary disease

INTRODUCTION

For the last two decades, long-acting β agonists (LABAs) have been a cornerstone in the management of chronic obstructive pulmonary disease (COPD). They relax airway smooth muscle and augment expiratory airflow, which reduces hyperinflation and improves dyspnea, functional capacity and quality of life. In recent years, Indacaterol, a LABA with an ultra-long duration of action (ultra-LABA), which only requires once-daily dosing, was approved by the FDA. The clinical efficacy of indacaterol is comparable, and, in some aspects better, than the currently available LABAs.

AREAS COVERED

This article reviews the pharmacological properties, clinical efficacy, safety and potential role of the ultra-LABAs in COPD management.

EXPERT OPINION

Ultra-LABAs are effective bronchodilators with a prolonged duration of action. By decreasing dosing frequency, ultra-LABAs potentially may improve respiratory medication adherence, which is associated with better survival and less healthcare utilization. In addition to their salubrious benefits, β agonists may produce untoward effects. Increased mortality and hospitalizations among patients with left ventricular heart failure, who were treated with β agonists, has caused concern about their use in patients with COPD and heart disease. Further experience and testing will determine the optimal role of ultra-LABAs in the management of COPD.

Discovery of AZD3199, An Inhaled Ultralong Acting β2 Receptor Agonist with Rapid Onset of Action

A series of dibasic des-hydroxy β2 receptor agonists has been prepared and evaluated for potential as inhaled ultralong acting bronchodilators. Determination of activities at the human β-adrenoreceptors demonstrated a series of highly potent and selective β2 receptor agonists that were progressed to further study in a guinea pig histamine-induced bronchoconstriction model. Following further assessment by onset studies in guinea pig tracheal rings and human bronchial rings contracted with methacholine (guinea pigs) or carbachol (humans), duration of action studies in guinea pigs after intratracheal (i.t.) administration and further selectivity and safety profiling AZD3199 was shown to have an excellent over all profile and was progressed into clinical evaluation as a new ultralong acting inhaled β2 receptor agonist with rapid onset of action.

Comparison of the bronchodilator and systemic effects of AZD3199, an inhaled ultra-long-acting β₂-adrenoceptor agonist, with formoterol in patients with asthma

OBJECTIVES

Pharmacologically mediated bronchodilation is important in the management of asthma, and is primarily achieved with β₂-agonists. Novel compounds should preferably have a longer duration of action and a better systemic side effect profile than established alternatives at comparable peak bronchodilation. This single-dose crossover study was conducted to investigate and compare with formoterol the bronchodilatory and systemic effects, tolerability and safety of AZD3199, a novel ultra-long-acting β₂-agonist (uLABA).

METHODS

Patients with asthma (n = 37) were randomized to receive AZD3199 (120, 480, 1920 µg), formoterol (9, 36 µg) or placebo inhaled via a Turbuhaler™. Bronchodilation was evaluated by maximum (E(max)) and average 22-26 h (E₂₂₋₂₆) forced expiratory volume in 1 second (FEV1). Serum potassium was evaluated by minimum (E(min)) and 0-4 h average (E(av)) determined from serial measurements. AZD3199 and formoterol were compared on the basis of relative dose potency. Adverse events, clinical laboratory tests and physical examinations were markers for safety and tolerability, with plasma AZD3199 as the indicator of drug exposure.

RESULTS

All active treatments dose-dependently increased E(max) and AZD3199 (480 and 1920 µg) and formoterol (36 µg) significantly increased E(₂₂₋₂₆) versus placebo. Relative dose potency between AZD3199 and formoterol was 50-fold on the microgram scale with respect to E max and 11-fold with respect to E(₂₂₋₂₆). Small, dose-dependent effects on potassium, heart rate and QTc were seen after administration of AZD3199 compared with placebo. These well-known dose-related class effects of β₂-agonists were mild. Notably, serum potassium suppression was less pronounced after AZD3199 compared with formoterol at similar bronchodilation. Overall, AZD3199 was well tolerated.

CONCLUSIONS

AZD3199 480 µg and 1920 µg produced 24-hour bronchodilation. At comparable peak bronchodilator effect, AZD3199 was associated with a lower level of systemic side effects than formoterol. AZD3199 was well tolerated, with no safety concerns identified to preclude further investigation. ClinicalTrials.gov study identifier: NCT00736489.