Category: Pulmonology

“Salmeterol and Fluticasone Propionate and Survival in Chronic Obstructive Pulmonary Disease”

by the Towards a Revolution in COPD Health (TORCH) investigators

N Engl J Med. 2007 Feb 22;356(8):775-89. [free full text]
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When the TORCH study was published in 2007, no prospective study to date had demonstrated a mortality benefit of inhaled corticosteroids (ICS) in COPD. Pulmonary inflammation occurs in COPD, and it had been hypothesized that ICS would improve COPD in multiple measures. Previously, ICS had been shown to reduce the frequency of COPD exacerbations, and retrospective data suggested that ICS reduced mortality, particularly when used in combination with a long-acting beta-agonist (LABA). TORCH was designed to evaluate prospectively the potential mortality benefit of combined ICS/LABA vs. ICS vs. LABA vs. placebo.

Population: COPD patients age 40-80, current or former smokers with ≥ 10-pack-year smoking hx, FEV₁ < 60% predicted value and increase in FEV₁ < 10% with albuterol administration, and prebronchodilator FEV₁/FVC ratio of ≤ 70%

Intervention: combination salmeterol 50 µg and fluticasone propionate 500 µg BID

Comparisons:

1. placebo BID
2. salmeterol 50 µg BID
3. fluticasone 500 µg BID

Note: all patients underwent a two-week run-in period during which the use of all corticosteroids and long-acting bronchodilators was stopped. Other classes COPD medications were allowed throughout the study.

Outcome:
Primary – time to all-cause mortality by 3 years, per log-rank test

Secondary

• time to all-cause mortality, per Cox proportional hazards model
• time to all-cause mortality, per log-rank test stratified by smoking status and country of residency
• frequency of COPD exacerbations
• quality of life per the St. George’s Respiratory Questionnaire
• lung function, per postbronchodilator spirometry
• incidence of pneumonia

 

Results:
6184 patients were randomized, but only 6112 were included in the final analyses (several sites excluded for not adhering to quality standards). The four groups were similar in all baseline characteristics (see Table 1).

All-cause mortality at 3 years was 12.6% in the combination-therapy group, 15.2% in the placebo group, 13.5% in the salmeterol group, and 16.0% in the fluticasone group. The hazard ratio for the comparison between combination-therapy and placebo was 0.825 (95% CI 0.681–1.002, p = 0.052, per log-rank test). See Figure 2B. This comparison was repeated in a pre-specified secondary analysis, using the Cox proportional hazards model, which yielded a HR of 0.811 (95% CI 0.670-0.982, p = 0.03), and in another pre-specified secondary analysis, using the log-rank test stratified according to smoking status and country of residency, which yielded a HR of 0.815 (95% CI 0.673-0.987, p = 0.04). In the primary analysis, the mortality risk did not differ among the salmeterol or fluticasone groups relative to the placebo group (see Table 2). Mortality risk in the combination-therapy group was less than that of the fluticasone group (HR 0.774, 95% CI 0.641-0.934, p = 0.007).

COPD exacerbations occurred at an annual rate of 0.85 in the combination therapy group and 1.13 in the placebo group, thus the rate ratio for exacerbations was 0.75 (95% CI 0.69-0.81, p < 0.001, NNT = 4). Exacerbation rates were also lower in the salmeterol and fluticasone groups (see Table 2).

The adjusted mean quality of life score per the St. George’s Respiratory Questionnaire improved in the combination-therapy, salmeterol, and fluticasone groups, and worsened slightly in the placebo group (see Table 3). All groups initially demonstrated an improvement in quality of life. In pairwise comparisons, combination therapy was superior to placebo, salmeterol, and fluticasone (p ranging from < 0.001 to 0.02).

Mean postbronchodilator FEV₁ averaged over 3 years improved in the combination therapy group and decreased in the other groups. In all groups, the overall trend was a decrease in FEV₁ following an initial improvement (see Figure 2E). In pairwise comparisons, combination therapy was superior to the other groups with respect to change in FEV₁ (see Table 3).

The incidence of pneumonia was increased in groups receiving an ICS. The probability of developing pneumonia within the 3 year period was 19.6% in the combination-therapy group, 12.3% in the placebo group, 13.3% in the salmeterol group, and 18.3% in the fluticasone group (p < 0.001 for comparison between both combination-therapy versus placebo and fluticasone versus placebo).

44% of patients in the placebo group withdrew from the study. Only 34% of the combination-therapy group withdrew.

Implication/Discussion:
In this large, international, double-blind, placebo-controlled, randomized, parallel-group trial of patients with COPD, combination therapy with ICS/LABA did not improve mortality when compared to a placebo. However, combination therapy improved the frequency of COPD exacerbations, improved quality of life, and slowed the decline in FEV₁ relative to placebo.

It is notable that, according to this study’s pre-specified secondary analyses of mortality per Cox proportional hazards and log-rank test stratified by smoking status and location, there was a mortality benefit of combination therapy.

The authors suspect that there is indeed a mortality benefit, but that the trial was underpowered to detect it. Furthermore, the higher rate of treatment-group withdrawal among placebo patients may have biased the study toward a null result, given the intention-to-treat analysis.

In the years since TORCH, meta-analyses that included TORCH have concluded that ICS therapy in COPD slows the rate of decline in FEV₁ and decreases the rate of COPD exacerbations when compared with placebo, but it does not reduce mortality.

Today, inhaled corticosteroids remain an integral component of our management of moderate to very severe COPD. See the Global Initiative for Chronic Obstructive Lung Disease (GOLD) Pocket Guide to COPD Diagnosis, Management, and Prevention (2017) pages 14-16.

Further Reading/References:
1. Wiki Journal Club
2. 2 Minute Medicine
3. UpToDate “Role of inhaled glucocorticoid therapy in stable COPD”
4. “Inhaled corticosteroids for stable chronic obstructive pulmonary disease.” Cochrane Database Syst Rev (2012).
5. Global Initiative for Chronic Obstructive Lung Disease (GOLD) Pocket Guide to COPD Diagnosis, Management, and Prevention (2017)

Summary by Duncan F. Moore, MD

“A 4-Year Trial of Tiotropium in Chronic Obstructive Pulmonary Disease”

by the Understanding Potential Impacts on Function with Tiotropium (UPLIFT) investigators

N Engl J Med. 2008 October 9; 359(15):1543-1554 [free full text]
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The 2008 UPLIFT trial was a four-year, randomized, double-blind, prospective study investigating whether or not tiotropium could reduce the rate of decline of FEV₁ (a common metric for COPD progression).  A previous retrospective study had shown a reduced rate of FEV₁ decline at one year with daily tiotropium. However, this finding had not been shown in any prospective study. As of 2008, smoking cessation was the only intervention demonstrated prospectively to decrease the rate of decline in FEV₁.

Population:  Patients were selected from 490 investigational centers in 37 countries

Inclusion: COPD, age ≥ 40, ≥ 10 pack-year smoking history, post-bronchodilator FEV₁ ≤70% of predicted value, and FEV₁/FVC ≤70%

Exclusion: history of asthma, COPD exacerbation or respiratory infection within the past 4 weeks, history of pulmonary resection, or use of supplemental O2 for more than 12 hours per day

Intervention: daily tiotropium 18mcg + usual respiratory medications

Control: daily placebo + usual respiratory medications

(Of note, in both arms, the usual respiratory medications could not include an anticholinergic.)

Outcomes:

Co-primary:

• Rate of decline in mean FEV₁ before bronchodilation
• Rate of decline in mean FEV₁ after bronchodilation

Secondary:

• Rate of decline in FVC
• Quality of life as measured by St. George’s Respiratory Questionnaire (SGRQ, ranges 0-100 with lower scores indicating improved quality)
• Rate of COPD exacerbations
• All-cause mortality

Results:
2987 patients were assigned to receive tiotropium, and 3006 were assigned to receive placebo. Baseline characteristics were similar between the two groups. 44.6% of placebo and 36.2% of tiotropium patients did not complete at least 45 months of treatment.

The primary outcomes of decline in mean FEV₁ either before or after bronchodilation were not significantly different between the two groups. Before bronchodilation, the difference in mean decline was 0 ml/year (p=0.95). After bronchodilation, the mean decline with tiotropium was 2 ml/year less than with placebo (p=0.21)

Regarding secondary outcomes:
There was no significant difference in rate of decline of FVC. The SGRQ was significantly lower (better) at all time points in the tiotropium group and, on average, was 2.7 points lower than in the placebo group (95% CI 2.0-3.3, p<0.001). The number of COPD exacerbations per year in the tiotropium group was 0.73 vs. 0.85 in the placebo group (RR 0.86, 95% CI 0.81-0.91; p<0.001), and the median time to first exacerbation was longer in the tiotropium group (16.7 months vs. 12.5 months, 95% CI 11.5-13.8,). All-cause mortality was not significantly different among the two groups (14.9% vs. 16.5%, HR 0.89; 95% CI 0.79-1.02; p=0.09). Respiratory failure developed in 88 patients in the tiotropium group vs. 120 in the placebo group (RR 0.67, 95% CI 0.51 to 0.89).

Discussion:
The UPLIFT study demonstrated no significant change in rate of decline in FEV₁ with tiotropium therapy compared to placebo. However, tiotropium therapy improved quality of life and reduced the frequency of COPD exacerbations and respiratory failure. Overall, this study is an excellent example how a well-designed prospective study can overturn the results of prior retrospective analyses.

The authors offered three potential reasons for the lack of difference in rate of FEV₁ decline among the groups. First, tiotropium may not actually alter the decline of lung function in COPD. Second, since both groups were permitted any respiratory medications other than another anticholinergic, there may have been a “ceiling effect” reached by the alternative medications, and thus no additional benefit offered by tiotropium therapy. Third, the authors noted the placebo group dropouts tended to be have more severe COPD, and so the remaining “healthy survivor” patients may have biased the group differences toward a null result.

Limitations of this study include a high dropout rate in both groups as well as a large male predominance (~75%) that limits generalizability. Finally, the limited clinical benefits of daily tiotropium use are not likely to be cost-effective. In 2010, researchers applied the treatment effects demonstrated in UPLIFT to an observational dataset of 56,321 tiotropium users in Belgium and estimated an average cost of 1.2 million euros per quality-adjusted life year (QALY) gained.

Further Reading/References:
1. Wiki Journal Club
2. 2 Minute Medicine
3. Neyt et al., “Tiotropium’s cost-effectiveness for the treatment of COPD: a cost-utility analysis under real-world conditions” (2010)

Summary by Gordon Pelegrin, MD