Treating patients with respiratory disease who smoke

Tigecycline Pharmacokinetic and Pharmacodynamic Profile in Patients with Chronic Obstructive Pulmonary Disease Exacerbation

BACKGROUND

We aimed to evaluate the pharmacokinetic profile of tigecycline in plasma and its penetration to sputum in moderately ill patients with an infectious acute exacerbation of chronic obstructive pulmonary disease (COPD).

METHODS

Eleven patients hospitalized with acute respiratory failure due to an acute COPD exacerbation with clinical evidence of an infectious cause received tigecycline 50 mg twice daily after an initial loading dose of 100 mg. Blood and sputum samples were collected at steady state after dose seven.

RESULTS

In plasma, mean C_max pl was 975.95 ± 490.36 ng/mL and mean C_min pl was 214.48 ±140.62 ng/mL. In sputum, mean C_{max sp} was 641.91 ± 253.07 ng/mL and mean C_{min sp} was 308.06 ± 61.7 ng/mL. In plasma, mean AUC _{0-12 pl} was 3765.89 ± 1862.23 ng*h/mL, while in sputum mean AUC _{0-12 sp} was 4023.27 ± 793.37 ng*h/mL. The mean penetration ratio for the 10/11 patients was 1.65 ± 1.35. The mean Free AUC_{0-24 pl}/MIC ratio for Streptococcus pneumoniae and Haemophilus influenzae was 25.10 ± 12.42 and 6.02 ± 2.97, respectively.

CONCLUSIONS

Our findings support the clinical effectiveness of tigecycline against commonly causative bacteria in COPD exacerbations and highlight its sufficient lung penetration in pulmonary infections of moderate severity.

Effect of smoking status on lung function, patient-reported outcomes, and safety among patients with COPD treated with indacaterol/glycopyrrolate: Pooled analysis of the FLIGHT1 and FLIGHT2 studies

BACKGROUND

Smoking continues to be a major risk factor for COPD and may impact the efficacy of COPD treatments, with guidelines supporting the crucial importance for current smokers of smoking cessation. A post-hoc analysis of the FLIGHT1 and FLIGHT2 studies assessed the impact of smoking status on the efficacy and safety of indacaterol/glycopyrrolate (IND/GLY) 27.5/15.6 μg twice daily versus its monocomponents or placebo in patients with COPD.

METHODS

This post-hoc analysis of pooled data from the replicate, 12-week, placebo-controlled FLIGHT1 and FLIGHT2 studies compared the efficacy and safety of IND/GLY with that of IND, GLY, and placebo in patients with moderate-to-severe COPD. Baseline data from 2038 patients were pooled and grouped by smoking status (52% were current smokers and 48% were ex-smokers). The effects of treatment on lung function, patient-reported outcomes (PROs), and safety were evaluated by baseline smoking status.

RESULTS

Treatment with IND/GLY resulted in significant improvements in lung function measurements compared with placebo, irrespective of smoking status. Improvements in St George's Respiratory Questionnaire and transition dyspnea index were significantly greater than placebo in both current and ex-smokers, whereas changes in COPD assessment test were significant only among current smokers. Improvements in lung function and PROs were greater with IND/GLY compared with its monocomponents in current and ex-smokers. The incidences of AEs and SAEs were similar between current and ex-smokers.

CONCLUSIONS

IND/GLY demonstrated significant improvements in lung function and PROs, independent of baseline smoking status. The safety profile of IND/GLY did not differ between current and ex-smokers.

Effect of smoking status on lung function, patient-reported outcomes, and safety among COPD patients treated with glycopyrrolate inhalation powder: pooled analysis of GEM1 and GEM2 studies

BACKGROUND

Smoking is a major risk factor for COPD and may impact the efficacy of COPD treatments; however, a large proportion of COPD patients continue to smoke following diagnosis.

METHODS

This post-hoc analysis of pooled data from the replicate 12-week, placebo-controlled GEM1 and GEM2 studies assessed the impact of smoking status on the efficacy and safety of glycopyrrolate 15.6 μg twice daily vs placebo in patients with moderate-to-severe COPD. Data from 867 patients enrolled in GEM1 and GEM2 were pooled for analysis and grouped by smoking status (57% current smokers, 43% ex-smokers). Forced expiratory volume in 1 s (FEV1) area under the curve from 0 to 12 h, trough FEV1, forced vital capacity, St George's Respiratory Questionnaire (SGRQ) total score, COPD assessment test (CAT) score, transition dyspnea index (TDI) focal score, daily symptom scores, and rescue medication use were assessed in current smokers and ex-smokers. Incidences of adverse events (AEs) and serious AEs (SAEs) were also assessed.

RESULTS

Treatment with glycopyrrolate resulted in significant improvements in all lung function measures, independent of smoking status. In both current and ex-smokers, changes from baseline in trough FEV1 were less marked in patients taking inhaled corticosteroids (ICS) than those not receiving ICS. Changes from baseline in SGRQ total score and rescue medication use were significantly greater with glycopyrrolate compared with placebo, regardless of smoking status. Changes in the CAT score, TDI focal score, and daily symptom scores significantly improved versus placebo, but only in current smokers. Improvements in patient-reported outcomes (PROs) with glycopyrrolate relative to placebo were numerically greater in current smokers than ex-smokers. The incidences of AEs and SAEs were similar regardless of smoking status.

CONCLUSIONS

In this post-hoc analysis of GEM1 and GEM2, glycopyrrolate use led to significant improvements in lung function, independent of baseline smoking status; improvements were less marked among patients receiving background ICS, regardless of baseline smoking status. Improvements in PROs were greater with glycopyrrolate than placebo, and the magnitude of changes was numerically greater among current smokers. The safety profile of glycopyrrolate was comparable between current smokers and ex-smokers.

Janeva E, Arsovska A, Isjanovski V. Altered therapeutic response towards inhaled corticosteroids in asthmatics –smokers with mild asthma

The exposure to tobacco smoke could cause bronchoconstriction and acute asthma attack. Smoking asthmatics have an insufficient therapeutic response to the standard therapy and unsatisfactory improvement of the respiratory function. In a randomized parallel study, a therapeutic response to inhaled fluticasone propionate in a dose of 250 µg twice per day was determined in 38 asthmatics with mild asthma, smokers and nonsmokers. Short-acting ß2 agonist (salbutamol) in a dosage of 0.1 mg/per inhaled dose was used as a rescue medication when needed. In patients, asthma was detected with a positive metacholine test and/or positive bronchodilatator response of > 12% with ≥ 200 ml increase of FEV1. They were randomized in two groups according to sex, age and starting values of FEV1. Before and after 6 weeks of treatment with fluticasone propionate of the previously corticosteroid-naive patients, lung function test (spirometry) was performed. A statistically significant effect (p<0.05) was achieved during the fluticasone propionate therapy in a group of non-smoking asthmatic patients. The same effect was not seen in the group of smoking asthmatics. Although the percentage of elevated FEV1 values was small, it was satisfactory because of the starting FEV1 values in patients with mild asthma. More studies are needed in asthmatics determining the asthma symptom score, the number of night awakenings due to asthma, the asthma exacerbations and the frequency of rescue therapy usage which will define the altered therapeutic response to inhaled corticosteroids in smoking asthmatics.

Janeva E, Arsovska A, Isjanovski V. The influence of inhaled corticosteroids on asthma control test in smokers and non-smokers with asthma

Smoking in asthmatics is responsible for the worsening of asthma symptoms, more frequent asthma exacerbations and hospitalizations and lowered quality of life. In smoking asthmatics the designated doses of the inhaled corticosteroid treatment are usually insufficient to accomplish total asthma control. Out of 54 screened adult patients up to 50 years old with mild asthma, 38 were involved in the study. They were divided in two groups: smokers and non-smokers. They received a total daily dosage of 500 µg of inhaled fluticasone propionate. A rescue medication, a short-acting ß2 agonist (salbutamol) in a dosage of 0.1 mg/per inhaled dose, was used when needed. Asthma was diagnosed by a positive metacholine provocation test and/or a positive bronchodilatator response. An asthma control test i.e. the ACT-TM questionnaire was performed before the beginning of the study and 6 weeks after the treatment with fluticasone propionate of the previous corticosteroid-naive patients. A statistically positive response (p<0.05) was reached in favor of non-smoking asthmatics. It can be concluded that ACT is a reliable tool to assess the effect of the topical corticosteroid treatment in non-smoking and smoking asthmatics. An achievement of better asthma control could be expected among both of the examined groups, but the effect of the intervention in the therapy is estimated to be more expressed within the group of asthmatic non-smokers. In smoking asthmatics there is a need for other therapeutic modalities such as increasing the dosage of inhaled corticosteroids, usage of combination therapy and/or adding low doses of aminophylline.

Effects of long-term smoking on the activity and mRNA expression of CYP isozymes in rats

BACKGROUND

To investigate the effect of long-term smoking on the activity and mRNA expression of cytochrome P450 (CYP) enzymes.

METHODS

Sprague-Dawley rats were exposed to passive smoking 6 cigarettes per day for 180 days. A cocktail solution which contained phenacetin (20 mg/kg), tolbutamide (5 mg/kg), chlorzoxazone (20 mg/kg) and midazolam (10 mg/kg) was given orally to rats. Blood samples were collected at pre-specified time points and the concentrations of probe drugs in plasma were determined by HPLC-MS/MS. The corresponding pharmacokinetic parameters were calculated by DAS 3.0. In addition, real-time RT-PCR was used to analyze the mRNA expression of CYP1A2, CYP2C11, CYP2E1 and CYP3A1 in rat liver.

RESULTS

There were no significant influences of pharmacokinetic profiles of chlorzoxazone in long-term smoking pretreated rats. But many pharmacokinetic profiles of phenacetin, tolbutamide, and midazolam in long-term smoking pretreated rats were affected significantly (P<0.05). The results suggested that long-term smoking had significant inhibition effects on CYP2C11 and CYP3A1 while CYP1A2 enzyme activity was induced. Furthermore, Long-term smoking had no effects on rat CYP2E1. The mRNA expression results were consistent with the pharmacokinetic results.

CONCLUSIONS

Alterations of CYP450 enzyme activities may fasten or slow down excretion with corresponding influence on drug efficacy or toxicity in smokers compared to nonsmokers, which may lead to clinical failures of lung cancer therapy or toxicity in smokers.

Cysteinyl leukotriene receptor-1 antagonists as modulators of innate immune cell function

Cysteinyl leukotrienes (cysLTs) are produced predominantly by cells of the innate immune system, especially basophils, eosinophils, mast cells, and monocytes/macrophages. Notwithstanding potent bronchoconstrictor activity, cysLTs are also proinflammatory consequent to their autocrine and paracrine interactions with G-protein-coupled receptors expressed not only on the aforementioned cell types, but also on Th2 lymphocytes, as well as structural cells, and to a lesser extent neutrophils and CD8⁺ cells. Recognition of the involvement of cysLTs in the immunopathogenesis of various types of acute and chronic inflammatory disorders, especially bronchial asthma, prompted the development of selective cysLT receptor-1 (cysLTR1) antagonists, specifically montelukast, pranlukast, and zafirlukast. More recently these agents have also been reported to possess secondary anti-inflammatory activities, distinct from cysLTR1 antagonism, which appear to be particularly effective in targeting neutrophils and monocytes/macrophages. Underlying mechanisms include interference with cyclic nucleotide phosphodiesterases, 5′-lipoxygenase, and the proinflammatory transcription factor, nuclear factor kappa B. These and other secondary anti-inflammatory mechanisms of the commonly used cysLTR1 antagonists are the major focus of the current review, which also includes a comparison of the anti-inflammatory effects of montelukast, pranlukast, and zafirlukast on human neutrophils in vitro, as well as an overview of both the current clinical applications of these agents and potential future applications based on preclinical and early clinical studies.

Inflammatory stimuli inhibit glucocorticoid-dependent transactivation in human pulmonary epithelial cells: rescue by long-acting beta2-adrenoceptor agonists

By repressing inflammatory gene expression, glucocorticoids are the most effective treatment for chronic inflammatory diseases such as asthma. However, in some patients with severe disease, or who smoke or suffer from chronic obstructive pulmonary disease, glucocorticoids are poorly effective. Although many investigators focus on defects in the repression of inflammatory gene expression, glucocorticoids also induce (transactivate) the expression of numerous genes to elicit anti-inflammatory effects. Using human bronchial epithelial (BEAS-2B) and pulmonary (A549) cells, we show that cytokines [tumor necrosis factor α (TNFα) and interleukin 1β], mitogens [fetal calf serum (FCS) and phorbol ester], cigarette smoke, and a G(q)-linked G protein-coupled receptor agonist attenuate simple glucocorticoid response element (GRE)-dependent transcription. With TNFα and FCS, this effect was not overcome by increasing concentrations of dexamethasone, budesonide, or fluticasone propionate. Thus, the maximal ability of the glucocorticoid to promote GRE-dependent transcription was reduced, and this was shown additionally for the glucocorticoid-induced gene p57(KIP2). The long-acting β(2)-adrenoceptor agonists (LABAs) formoterol fumarate and salmeterol xinafoate enhanced simple GRE-dependent transcription to a level that could not be achieved by glucocorticoid alone. In the presence of TNFα or FCS, which repressed glucocorticoid responsiveness, these LABAs restored glucocorticoid-dependent transcription to levels that were achieved by glucocorticoid alone. Given the existence of genes, such as p57(KIP2), which may mediate anti-inflammatory actions of glucocorticoids, we propose that repression of transactivation represents a mechanism for glucocorticoid resistance and for understanding the clinical benefit of LABAs as an add-on therapy in asthma and chronic obstructive pulmonary disease.

Challenges of treating asthma in people who smoke

Cigarette smoking is common in asthma and is associated with poor symptom control and a reduced therapeutic response to inhaled and oral corticosteroids as compared with nonsmokers with asthma. This review examines the range of adverse health effects of smoking in asthma, the inflammatory mechanisms that may influence the efficacy of current drugs and discusses potential future therapeutic directions.

Long-term efficacy of tiotropium in relation to smoking status in the UPLIFT trial

UPLIFT (Understanding Potential Long-Term Improvements in Function with Tiotropium), a 4-yr trial of tiotropium in chronic obstructive pulmonary disease, allowed for assessment of smoking status on long-term responses to maintenance bronchodilator therapy. 5,993 patients were randomised (tiotropium/placebo). Lung function, St George's Respiratory Questionnaire, exacerbations and adverse events were followed. Patients were characterised as continuing smokers (CS), continuing ex-smokers (CE), or intermittent smokers (IS) based on self-reporting smoking behaviour. 60%, 14% and 26% of patients were CE, CS and IS, respectively. The rate of forced expiratory volume in 1 s (FEV(1)) decline for placebo patients was most rapid in CS (-52+/-4, -37+/2 and -23+/2 mL.yr(-1) in CS, IS, and CE, respectively). Tiotropium did not alter FEV(1) decline, but was associated with significant improvements in pre- and post-bronchodilator FEV(1) over placebo that persisted throughout the 4-yr trial for each smoking status (pre-bronchodilator: 127, 55 and 97 mL at 48 months in CS, IS and CE, respectively; p< or =0.0003). Tiotropium reduced exacerbation risk in CS (HR (95% CI) 0.80 (0.67-0.95)), in CE (0.85 (0.79-0.92)) and trended towards significance in IS (0.89 (0.79-1.00)). At 4 yrs, St George's Respiratory Questionnaire for tiotropium patients improved the most in CS (-4.63 units, p = 0.0006) and the least in IS (-0.60 units, p = 0.51), [corrected] compared with control. Tiotropium provided long-term benefits irrespective of smoking status, although differences among categories were observed.

Asthma in smokers: challenges and opportunities

PURPOSE OF REVIEW

Cigarette smoking in asthma is associated with poor symptom control and reduced sensitivity to corticosteroids. We summarize recent evidence supporting the adverse effects of smoking in asthma and consider strategies to manage these patients.

RECENT FINDINGS

Smokers have more severe symptoms and are more likely to be admitted to hospital due to poorly controlled asthma compared with nonsmokers with asthma. Possible causes of reduced sensitivity to inhaled corticosteroids in smokers with asthma are noneosinophilic airway inflammation, impaired glucocorticoid receptor function, and/or reduced histone deacetylase activity. Smoking cessation improves asthma control, but quit rates are low. The optimal drug therapy for smokers with asthma is not established due, in part, to the small number of clinical trials performed in these patients. Preliminary data, however, suggest that leukotriene-receptor antagonists may have a beneficial effect in smokers with mild asthma.

SUMMARY

Cigarette smoking in asthma is a risk factor for poor asthma control and reduced sensitivity to corticosteroids. Every effort should be made to encourage individuals with asthma who smoke to quit. Clinical trials are required to identify therapies that restore corticosteroid sensitivity or directly improve symptom control in individuals with asthma who are unable to stop smoking.