Eosinophil-guided therapy may cut steroid exposure in patients with asthma exacerbations

A study conducted by researchers from Singapore shows that an eosinophil-guided strategy safely reduces corticosteroid exposure in hospitalized asthma patients with non-eosinophilic exacerbations.

Eosinophil-guided care (EGC), which involves prescribing prednisolone based on blood eosinophil count (BEC), was noninferior to usual care (UC) for treatment failure.

The treatment failure rates were 10.9 percent and 7.3 percent in the EGC and UC groups, respectively. A comparison between groups yielded an absolute difference of 3.6 percent (95 percent confidence interval [CI], −8.9 to 16.2 percent), in favour of UC.

“The upper limit of the CI was less than, and did not cross, the prespecified 20 percent noninferiority margin; hence, the primary outcome of noninferiority was met,” said the investigators, led by Dr Anthony Yii from Changi General Hospital, Singapore.

The cumulative corticosteroid dose was significantly lower in non-eosinophilic than eosinophilic patients in the EGC group (136 vs 214 mg; p=0.0004) but not in the UC group (186 vs 211 mg; p=0.18). [Thorax 2026;81:238-245]

Secondary outcomes

The EGC and UC groups had no significant differences in length of stay (2.5 vs 2.7 days; p=0.68), additional systemic steroid bursts at 14 days (11.5 percent vs 8 percent; p=0.79), pneumonia incidence at 30 days (2 percent for both; p=1.00), cumulative incidence of recurrent exacerbation at 1 year (hazard ratio, 0.76; p=0.52), and Asthma Control Questionnaire-5 change at 7, 14, 30, and 90 days (fixed-effect coefficient, −0.20; p=0.36).

There were no incident cases of gastrointestinal bleeds, peptic ulcers, sepsis, venous thromboembolism, or fractures, nor were there any deaths, at 30 and 90 days.

Personalized corticosteroid stewardship

Current guidelines recommend 5–7 days of systemic corticosteroids for all asthma exacerbations. “[This] is an entrenched clinical practice but may undermine corticosteroid stewardship by missing opportunities for shorter courses in some patients, potentially resulting in unnecessary steroid exposure and increased risk of side effects,” the investigators explained.

“Because exacerbations recur throughout a patient’s lifetime, repeated exposure further amplifies long-term harms,” they continued. “Patients may even be willing to forego the therapeutic benefits of corticosteroids to avoid adverse effects, underscoring the need for effective corticosteroid stewardship strategies to minimize unnecessary exposure during exacerbations.”

Biomarker-guided approaches may reduce unnecessary steroid exposure, specifically in non-eosinophilic exacerbations, which are less responsive to corticosteroids, the investigators added.

The study included 110 patients (mean age 48.4 years, 61.8 percent women) admitted to the general wards at Singapore General Hospital and Changi General Hospital for acute exacerbation of physician-diagnosed asthma, who had not taken systemic corticosteroids within 7 days of presentation.

The participants were randomized 1:1 to EGC or UC. In the EGC group, patients received oral prednisolone 0.5 mg/kg/day (limited to 20–50 mg/day) QD for 3 days for non-eosinophilic exacerbations (BEC <300 cells/μL) or 5 days for eosinophilic exacerbations (BEC ≥300 cells/μL). In the UC group, all participants received the standard 5-day prednisolone therapy irrespective of BEC.

“Our trial is the first to investigate the feasibility and safety of using BEC to reduce systemic steroid exposure in asthma exacerbations, and we were able to demonstrate that the eosinophil-guided strategy can be used to shorten the duration of systemic corticosteroid use without compromising safety,” Yii and colleagues said.

The study suggests that using BEC to guide systemic corticosteroid therapy is a promising strategy for personalized corticosteroid stewardship in acute exacerbations and minimizing adverse effects in asthma management, they added, calling for further validation in larger, more diverse trials.