Triple Therapy in COPD: Time for Adaptive Selection Trials

Observational studies to emulate randomized trials: Some real-world barriers

The randomized controlled trial (RCT) forms the basis for drug approval by regulatory agencies. Observational studies using existing data from healthcare databases now also provide real-world evidence (RWE) in regulatory decision-making. Several initiatives are assessing the value of RWE by conducting observational studies that emulate published RCTs. While many RCTs are straightforward to emulate, others are challenging. We describe three RCT design aspects that pose challenges for observational studies. First are trials that enrol already treated subjects who must discontinue these treatments at the time of randomization, which can distort the comparison with observational studies. Second is the inclusion of a run-in phase, especially to exclude non-compliant subjects from the trial. Third are trials that evaluate the effect of weaning off treatment. In conclusion, future randomized trials that aim to be emulated by observational studies could consider study designs that allow emulation and thus provide valid and complementary RWE.

Effects of triple therapy on disease burden in patients of GOLD groups C and D: results from the observational COPD cohort COSYCONET

BACKGROUND

Randomized controlled trials described beneficial effects of inhaled triple therapy (LABA/LAMA/ICS) in patients with chronic obstructive pulmonary disease (COPD) and high risk of exacerbations. We studied whether such effects were also detectable under continuous treatment in a retrospective observational setting.

METHODS

Data from baseline and 18-month follow-up of the COPD cohort COSYCONET were used, including patients categorized as GOLD groups C/D at both visits (n = 258). Therapy groups were defined as triple therapy at both visits (triple always, TA) versus its complement (triple not always, TNA). Comparisons were performed via multiple regression analysis, propensity score matching and inverse probability weighting to adjust for differences between groups. For this purpose, variables were divided into predictors of therapy and outcomes.

RESULTS

In total, 258 patients were eligible (TA: n = 162, TNA: n = 96). Without adjustments, TA patients showed significant (p < 0.05) impairments regarding lung function, quality of life and symptom burden. After adjustments, most differences in outcomes were no more significant. Total direct health care costs were reduced but still elevated, with inpatient costs much reduced, while costs of total and respiratory medication only slightly changed.

CONCLUSION

Without statistical adjustment, patients with triple therapy showed multiple impairments as well as elevated treatment costs. After adjusting for differences between treatment groups, differences were reduced. These findings are compatible with beneficial effects of triple therapy under continuous, long-term treatment, but also demonstrate the limitations encountered in the comparison of controlled intervention studies with observational studies in patients with severe COPD using different types of devices and compounds.

Eligibility of patients with chronic obstructive pulmonary disease for inclusion in randomised control trials investigating triple therapy: a study using routinely collected data

BACKGROUND

Randomised control trials (RCTs) with strict eligibility criteria can lead to trial populations not commonly seen in clinical practice. We described the proportion of people with chronic obstructive pulmonary disease (COPD) in England eligible for RCTs investigating treatment with triple therapy.

METHODS

MEDLINE and Clinicaltrials.gov were searched for RCTs investigating triple therapy and eligibility criteria for each trial were extracted. Using routinely collected primary care data from Clinical Practice Research Datalink Aurum linked with Hospital Episode Statistics, we defined a population of COPD patients registered at a general practice in England, who were ≥ 40 years old, and had a history of smoking. Inclusion date was January 1, 2020. Patients who died earlier or left the general practice were excluded. Eligibility criteria for each RCT was applied to the population of COPD patients and the proportion of patients meeting each trial eligibility criteria were described.

RESULTS

26 RCTs investigating triple therapy were identified from the literature. The most common eligibility criteria were post-bronchodilator FEV1% predicted 30-80%, ≥ 2 moderate/≥ 1 severe exacerbations 12-months prior, no moderate exacerbations one-month prior and no severe exacerbations three-months prior, and the use of maintenance therapy or ICS use prior to inclusion. After applying each RCT eligibility criteria to our population of 79,810 COPD patients, a median of 11.2% [interquartile range (IQR) 1.8-17.4] of patients met eligibility criteria. The most discriminatory criteria included the presence exacerbations of COPD and previous COPD related medication use with a median of 67.6% (IQR 8.5-73.4) and 63% (IQR 69.3-38.4) of COPD patients not meeting these criteria, respectively.

CONCLUSION

Data from these RCTs may not be generalisable to the wider population of people with COPD seen in everyday clinical practice and real-world evidence studies are needed to supplement trials to understand effectiveness in all people with COPD.

Rational use of inhaled corticosteroids for the treatment of COPD

Inhaled corticosteroids (ICS) are the mainstay of treatment for asthma, but their role in chronic obstructive pulmonary disease (COPD) is debated. Recent randomised controlled trials (RCTs) conducted in patients with COPD and frequent or severe exacerbations demonstrated a significant reduction (~25%) in exacerbations with ICS in combination with dual bronchodilator therapy (triple therapy). However, the suggestion of a mortality benefit associated with ICS in these trials has since been rejected by the European Medicines Agency and US Food and Drug Administration. Observational evidence from routine clinical practice demonstrates that dual bronchodilation is associated with better clinical outcomes than triple therapy in a broad population of patients with COPD and infrequent exacerbations. This reinforces guideline recommendations that ICS-containing maintenance therapy should be reserved for patients with frequent or severe exacerbations and high blood eosinophils (~10% of the COPD population), or those with concomitant asthma. However, data from routine clinical practice indicate ICS overuse, with up to 50-80% of patients prescribed ICS. Prescription of ICS in patients not fulfilling guideline criteria puts patients at unnecessary risk of pneumonia and other long-term adverse events and also has cost implications, without any clear benefit in disease control. In this article, we review the benefits and risks of ICS use in COPD, drawing on evidence from RCTs and observational studies conducted in primary care. We also provide a practical guide to prescribing ICS, based on the latest global treatment guidelines, to help primary care providers identify patients for whom the benefits of ICS outweigh the risks.

Impact of triple therapy on mortality in COPD

Only a few therapies have been shown to prolong survival in specific patients with COPD. In recent years, the IMPACT and the ETHOS trials suggested that triple therapy (a combination of inhaled corticosteroid (ICS), long-acting muscarinic antagonist (LAMA) and long-acting β2-agonist (LABA) given in a single inhaler) may reduce mortality compared with dual bronchodilation.

These results need however to be interpreted with caution. These trials were not powered by design to evaluate the impact of triple therapy on mortality as mortality was a secondary outcome. In addition, mortality reduction has to be put in perspective with the low mortality rate in both studies (<2%). Furthermore, a key methodological issue is that up to 70–80% of patients had ICS withdrawal at the enrolment in the LABA/LAMA arms, but none in the ICS-containing treatment arms. It is possible that ICS withdrawal may have contributed to some early death events. Finally, the inclusion and exclusion criteria of both trials were designed to select patients likely to respond to ICS.

There are no conclusive data yet that triple therapy reduces mortality in COPD. Future, well-designed and -powered trials are needed to validate the findings on mortality.

Triple therapy in COPD: understanding the data

Effectiveness of single-inhaler triple therapy on exacerbation risk and mortality in COPD is exaggerated in IMPACT and ETHOS trials from confounding by prior ICS discontinuation: effectiveness fades in analyses and studies with no prior ICS discontinuation https://bit.ly/3tOgNdW.

Single-Inhaler Triple versus Dual Bronchodilator Therapy in COPD: Real-World Comparative Effectiveness and Safety

Purpose

Randomized trials report that single-inhaler triple therapy is more effective than dual bronchodilators at reducing exacerbations in patients with chronic obstructive pulmonary disease (COPD). However, this effect may have been influenced by the forced withdrawal of inhaled corticosteroids (ICS) at randomization. We used an adaptive selection new-user design to compare single-inhaler triple therapy with dual bronchodilators in real-world clinical practice.

Patients and Methods

We identified a cohort of COPD patients, 40 years or older, treated during 2017–2020, from the United Kingdom’s Clinical Practice Research Datalink, a real-world practice setting. ICS-naïve patients initiating single-inhaler triple therapy or dual bronchodilators were compared on the incidence of COPD exacerbation and pneumonia over one year, after adjustment by propensity score weighting.

Results

The cohort included 4106 new users of single-inhaler triple therapy and 29,702 of dual bronchodilators. Single-inhaler triple therapy was the first maintenance treatment in 44% of the users and 43% had no COPD exacerbations in the prior year. The adjusted hazard ratio (HR) of a first moderate or severe exacerbation with triple therapy relative to dual bronchodilators was 1.08 (95% confidence interval (CI): 1.00–1.16). Among patients with two or more prior exacerbations the HR was 0.83 (95% CI: 0.74–0.92), while for those with prior asthma diagnosis it was 0.86 (95% CI: 0.70–1.06) and with blood eosinophil count >300 cells/µL it was 0.89 (95% CI: 0.76–1.05). The incidence of severe pneumonia was increased with triple therapy (HR 1.50; 95% CI: 1.29–1.75).

Conclusion

In a real-world setting of COPD treatment among ICS-naïve patients, thus unaffected by ICS withdrawal, single-inhaler triple therapy was not more effective than dual bronchodilators at reducing the incidence of exacerbation, except among patients with multiple exacerbations. Single-inhaler triple therapy should be initiated mainly in patients with multiple exacerbations while, for most others, dual bronchodilators are just as effective whilst avoiding the excess risk of severe pneumonias.

A Pooled Analysis of Mortality in Patients with COPD Receiving Dual Bronchodilation with and without Additional Inhaled Corticosteroid

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Conclusion