The distribution of blood eosinophil levels in a Japanese COPD clinical trial database and in the rest of the world

Abstract

BackgroundBlood eosinophil measurements may help to guide physicians on the use of inhaled corticosteroids (ICS) for patients with chronic obstructive pulmonary disease (COPD). Emerging data suggest that COPD patients with higher blood eosinophil counts may be at higher risk of exacerbations and more likely to benefit from combined ICS/long-acting beta2-agonist (LABA) treatment than therapy with a LABA alone. This analysis describes the distribution of blood eosinophil count at baseline in Japanese COPD patients in comparison with non-Japanese COPD patients.MethodsA post hoc analysis of eosinophil distribution by percentage and absolute cell count was performed across 12 Phase II–IV COPD clinical studies (seven Japanese studies [N=848 available absolute eosinophil counts] and five global studies [N=5,397 available eosinophil counts] that included 246 Japanese patients resident in Japan with available counts). Blood eosinophil distributions were assessed at baseline, before blinded treatment assignment.FindingsAmong Japanese patients, the median (interquartile range) absolute eosinophil count was 170 cells/mm3 (100–280 cells/mm3). Overall, 612/1,094 Japanese patients (56%) had an absolute eosinophil count ≥150 cells/mm3 and 902/1,304 Japanese patients (69%) had a percentage eosinophil ≥2%. Among non-Japanese patients, these values were 160 (100–250) cells/mm3, 2,842/5,151 patients (55%), and 2,937/5,155 patients (57%), respectively. The eosinophil distribution among Japanese patients was similar to that among non-Japanese patients. Within multi-country studies with similar inclusion criteria, the eosinophil count was numerically lower in Japanese compared with non-Japanese patients (median 120 vs 160 cells/mm3).InterpretationThe eosinophil distribution in Japanese patients seems comparable to that of non-Japanese patients; although within multi-country studies, there was a slightly lower median eosinophil count for Japanese patients compared with non-Japanese patients. These findings suggest that blood eosinophil data from global studies are of relevance in Japan.

Prevalence and Baseline Clinical Characteristics of Eosinophilic Chronic Obstructive Pulmonary Disease: A Meta-Analysis and Systematic Review

“…We searched 192 studies, of which nineteen studies (7)(8)(9)(10)(11)(12)(13)(14)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27) with 40,112 participants were included in the final analysis (Figure 1). According to the cut-off level of 2% eosinophil in the blood, 22,043 and 18,069 patients were classified as having eosinophilic and non-eosinophilic COPD, respectively.…”

Economic Impact of Reducing Inappropriate Inhaled Corticosteroids Use in Patients With Chronic Obstructive Pulmonary Disease: ISPOR's Guidance on Budget Impact in Practice

“…Indeed, in the most recent guidelines, GOLD recommends ICS explicitly in patients with high (>300 cells/mm 3 ) eosinophil counts, which is present in +/-20% of the COPD population. 1,40,41 Yet, to also account for other risk groups where ICS may be beneficial (e.g. frequent exacerbators, asthma-overlap.…”

“…frequent exacerbators, asthma-overlap. 1,[40][41][42][43][44][45] ), we considered a slightly higher percentage of ICS (i.e. 25%) in the new treatment mix.…”

“…Additionally, there is some uncertainty on the percentage that benefits from remaining on ICS treatment, as data on the demographics and associated treatment regimes in the Netherlands of specific subgroups are not currently available, such as the proportion of patients with asthma or blood eosinophil counts (>300 cells/mm 3 ). 40,41 The sensitivity analysis shows a considerable impact of the proportion of patients that continues to use ICS treatment on the budget impact difference; with a 5% decrease or increase of this proportion resulting in around a 15% increased or decreased budget impact difference respectively. Exacerbation history was assumed to be the same across the various treatment options, although we would suspect patients with triple therapy to have had more exacerbations in the past, as compared to e.g.…”

Is Blood Eosinophil Count a Biomarker for Chronic Obstructive Pulmonary Disease in a Real-World Clinical Setting? Predictive Property and Longitudinal Stability in Japanese Patients

“…In the 5th version of the Japanese guidelines published by The Japanese Respiratory Society in 2018, the description reads that ICS should be given only in patients with asthma-complicated COPD or Asthma and COPD Overlap (ACO) [12]. It is reported that the blood eosinophil data from global studies are of relevance in Japan although there was a slightly lower median eosinophil count for Japanese patients within multi-country studies [13]. One of the opposing views is that BEC may be liable to variation and considered to be unreliable as a biomarker [14][15][16][17][18][19][20][21][22][23][24].…”