Characterisation of exacerbation risk and exacerbator phenotypes in the POET-COPD trial

Tiotropium and Salmeterol in COPD Patients at Risk of Exacerbations: A Post Hoc Analysis from POET-COPD(®)

Introduction

Among patients with chronic obstructive pulmonary disease (COPD), the frequency and severity of past exacerbations potentiates future events. The impact of current therapies on exacerbation frequency and severity in patients with different exacerbation risks is not well known.

Methods

A post hoc analysis of patients at low (≤1 exacerbation [oral steroids/antibiotics requirement] and no COPD-related hospitalization in the year preceding trial entry) or high (≥2 exacerbations [oral steroids/antibiotics requirement] or ≥1 COPD-related hospitalization[s] in the year preceding trial entry) exacerbation risk, from the Prevention of Exacerbations with Tiotropium in Chronic Obstructive Pulmonary Disease (POET-COPD^®) database.

Results

Compared with salmeterol, tiotropium significantly increased time to first COPD exacerbation (hazard ratio 0.84; 95% confidence interval [CI] 0.76–0.92; p = 0.0002) and reduced the number of COPD exacerbations (rate ratio 0.90; 95% CI 0.81–0.99; p = 0.0383) in patients at high exacerbation risk. With treatment, the risk of remaining in the high-risk exacerbator subgroup was statistically lower with tiotropium versus salmeterol (risk ratio [RR] 0.89; 95% CI 0.80–1.00; p = 0.0478). For low-risk patients, time to first COPD exacerbation and number of COPD exacerbations were numerically lower with tiotropium versus salmeterol. With treatment, the risk of transitioning from a low to a high exacerbation risk was lower with tiotropium versus salmeterol (RR 0.87; 95% CI 0.71–1.07; p = 0.1968).

Discussion

This analysis confirms the higher efficacy of tiotropium versus salmeterol in prolonging time to first COPD exacerbation and reducing number of exacerbations in patients both at low and high exacerbation risk.

Funding

Boehringer Ingelheim and Pfizer.

Clinical trial registration number: ClinicalTrials.gov NCT00563381.

Electronic supplementary material

The online version of this article (doi:10.1007/s12325-015-0216-2) contains supplementary material, which is available to authorized users.

Defining phenotypes in COPD: an aid to personalized healthcare

The diagnosis of chronic obstructive pulmonary disease (COPD) is based on a post-bronchodilator fixed forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) <70 % ratio and the presence of symptoms such as shortness of breath and productive cough. Despite the simplicity in making a diagnosis of COPD, this morbid condition is very heterogeneous, and at least three different phenotypes can be recognized: the exacerbator, the emphysema-hyperinflation and the overlap COPD-asthma. These subgroups show different clinical and radiological features. It has been speculated that there is an enormous variability in the response to drugs among the COPD phenotypes, and it is expected that subjects with the same phenotype will have a similar response to each specific treatment. We believe that phenotyping COPD patients would be very useful to predict the response to a treatment and the progression of the disease. This personalized approach allows identification of the right treatment for each COPD patient, and at the same time, leads to improvement in the effectiveness of therapies, avoidance of treatments not indicated, and reduction in the onset of adverse effects. The objective of the present review is to report the current knowledge about different COPD phenotypes, focusing on specific treatments for each subgroup. However, at present, COPD phenotypes have not been studied by randomized clinical trials and therefore we hope that well designed studies will focus on this topic.

Efficacy and safety of once-daily QVA149 compared with the free combination of once-daily tiotropium plus twice-daily formoterol in patients with moderate-to-severe COPD (QUANTIFY): a randomised, non-inferiority study

Background

QVA149 is a once-daily (o.d.) inhaled dual bronchodilator containing a fixed-dose combination of the long-acting β₂-agonist indacaterol and the long-acting muscarinic antagonist glycopyrronium for the treatment of COPD. The QUANTIFY study compared QVA149 with a free-dose bronchodilator combination of tiotropium plus formoterol (TIO+FOR) in improving health-related quality of life (HRQoL) of patients with COPD.

Methods

This multicentre, blinded, triple-dummy, parallel-group, non-inferiority study randomised patients aged ≥40 years with moderate-to-severe COPD (post-bronchodilator forced expiratory volume in 1 s (FEV₁) ≥30% to <80% predicted) to QVA149 110/50 µg o.d. or TIO 18 µg o.d.+ FOR 12 µg twice daily (1:1) for 26 weeks. The primary endpoint was to demonstrate non-inferiority in HRQoL assessed using St George's Respiratory Questionnaire-COPD (SGRQ-C). The prespecified non-inferiority margin was 4 units. Secondary endpoints included Transition Dyspnoea Index (TDI) score, pre-dose FEV₁, forced vital capacity (FVC) and safety.

Results

Of the 934 patients randomised (QVA149=476 and TIO+FOR=458), 87.9% completed the study. At week 26, non-inferiority was met for SGRQ-C (QVA149 vs TIO+FOR; difference: –0.69 units; 95% CI −2.31 to 0.92; p=0.399). A significantly higher percentage of patients achieved a clinically relevant ≥1 point improvement in TDI total score with QVA149 (49.6%) versus TIO+FOR (42.4%; p=0.033). QVA149 significantly increased pre-dose FEV₁ (+68 mL, 95% CI 37 mL to 100 mL; p<0.001) and FVC (+74 mL, 95% CI 24 mL to 125 mL; p=0.004) compared with TIO+FOR at week 26. The incidence of adverse events was comparable between both treatments (QVA149=43.7% and TIO+FOR=42.6%).

Conclusions

QVA149 is non-inferior to TIO+FOR in improving HRQoL, with clinically meaningful and significant improvements in breathlessness and lung function in patients with COPD.

Trial registration number

NCT01120717.

Characterisation of the frequent exacerbator phenotype in COPD patients in a large UK primary care population

BACKGROUND

The 'frequent exacerbator' is recognised as an important phenotype in COPD. Current understanding about this phenotype comes from prospective longitudinal clinical trials in secondary/tertiary care with little information reported in primary care populations.

AIMS

To characterize the frequent-exacerbator phenotype and identify associated risk factors in a large UK primary care COPD population.

METHODS

Using a large database of primary care patients from 80 UK general practices, patients were categorised using GOLD 2014 criteria into high and low risk groups based on exacerbation history. A multivariate logistic regression model was used to investigate covariates associated with the frequent-exacerbator phenotype and risk of experiencing a severe exacerbation (leading to hospitalisation).

RESULTS

Of the total study population (n = 9219), 2612 (28%) fulfilled the criteria for high risk frequent-exacerbators. Independent risk factors (adjusted odds ratio [95% CI]) for ≥2 exacerbations were: most severely impaired modified Medical Research Council (mMRC) dyspnoea score (mMRC grade 4: 4.37 [2.64-7.23]), lower FEV1 percent predicted (FEV1 <30%: 2.42 [1.61-3.65]), co-morbid cardiovascular disease (1.42 [1.19-1.68]), depression (1.56 [1.22-1.99]) or osteoporosis (1.54 [1.19-2.01]), and female gender (1.20 [1.01-1.43]). Older patients (≥75 years), those with most severe lung impairment (FEV1 <30%), those with highest mMRC score and those with co-morbid osteoporosis were identified as most at risk of experiencing exacerbations requiring hospitalisation.

CONCLUSIONS

Although COPD exacerbations occur across all grades of disease severity, female patients with high dyspnoea scores, more severely impaired lung function and co-morbidities are at greatest risk. Elderly patients, with severely impaired lung function, high mMRC scores and osteoporosis are associated with experience of severe exacerbations requiring hospitalisation.

Azithromycin maintenance treatment in patients with frequent exacerbations of chronic obstructive pulmonary disease (COLUMBUS): a randomised, double-blind, placebo-controlled trial

BACKGROUND

Macrolide resistance is an increasing problem; there is therefore debate about when to implement maintenance treatment with macrolides in patients with chronic obstructive pulmonary disease (COPD). We aimed to investigate whether patients with COPD who had received treatment for three or more exacerbations in the previous year would have a decrease in exacerbation rate when maintenance treatment with azithromycin was added to standard care.

METHODS

We did a randomised, double-blind, placebo-controlled, single-centre trial in The Netherlands between May 19, 2010, and June 18, 2013. Patients (≥18 years) with a diagnosis of COPD who had received treatment for three or more exacerbations in the previous year were randomly assigned, via a computer-generated randomisation sequence with permuted block sizes of ten, to receive 500 mg azithromycin or placebo three times a week for 12 months. Randomisation was stratified by use of long-term, low-dose prednisolone (≤10 mg daily). Patients and investigators were masked to group allocation. The primary endpoint was rate of exacerbations of COPD in the year of treatment. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00985244.

FINDINGS

We randomly assigned 92 patients to the azithromycin group (n=47) or the placebo group (n=45), of whom 41 (87%) versus 36 (80%) completed the study. We recorded 84 exacerbations in patients in the azithromycin group compared with 129 in those in the placebo group. The unadjusted exacerbation rate per patient per year was 1·94 (95% CI 1·50-2·52) for the azithromycin group and 3·22 (2·62-3·97) for the placebo group. After adjustment, azithromycin resulted in a significant reduction in the exacerbation rate versus placebo (0·58, 95% CI 0·42-0·79; p=0·001). Three (6%) patients in the azithromycin group reported serious adverse events compared with five (11%) in the placebo group. During follow-up, the most common adverse event was diarrhoea in the azithromycin group (nine [19%] patients vs one [2%] in the placebo group; p=0·015).

INTERPRETATION

Maintenance treatment with azithromycin significantly decreased the exacerbation rate compared with placebo and should therefore be considered for use in patients with COPD who have the frequent exacerbator phenotype and are refractory to standard care.

FUNDING

SoLong Trust.