JMIR Publications

ABSTRACT

Background:

Asthma attacks are a common and important problem. Someone has an asthma attack in the UK every 10 seconds. Asthma attacks cause cough, wheeze, breathlessness, and tight chest and are highly stressful for patients. They result in reduced quality of life with days lost to work or school. Asthma attacks are treated with oral corticosteroids (OCS), but these have many short- and long-term side effects. Asthma monoclonal antibodies (mAbs) have revolutionised the treatment of severe asthma by reducing asthma attacks and OCS burden by over 50%. But some people still experience attacks on mAbs. The MEX study showed that residual asthma attacks were broadly eosinophilic (high Fraction exhaled nitric oxide (FeNO)) and non-eosinophilic (low FeNO), but it did not measure response to OCS treatment. There is an evidence gap in understanding the clinical and inflammatory response of using OCS to treat residual asthma attacks in patients taking asthma mAbs.

Objective:

In people established on long-term asthma mAb treatment: 1. The primary objective is to compare the clinical recovery between FeNO-high and FeNO-low attacks after acute treatment with oral prednisolone. 2. The exploratory objective is to compare the inflammatory response to acute treatment with oral prednisolone between FeNO-high and FeNO-low attacks.

Methods:

BOOST is a single-centre, prospective observational study of 60 adults established on long-term asthma mAb treatment, who receive acute treatment with oral prednisolone (usual care) for an asthma attack. The primary outcome will be the proportion of treatment failure at day 28 following attack. Secondary outcomes will be change in Forced Expiratory Volume in 1 second (FEV1) and Visual Analogue Scale (VAS) symptom score between stable state, attack, day 7, and day 28. Exploratory outcomes include the change in sputum, nasal and blood inflammometry between stable state, attack, day 7, and day 28.

Results:

The anticipated last attack visit is in December 2023. Data analysis and publication will take place in 2024.

Conclusions:

We will test the hypothesis that there is a difference in the rate of recovery of clinical and inflammatory measures between FeNO-high and FeNO-low asthma attacks occurring in patients on mAb therapy. The study data will help power a future randomised, placebo-controlled trial of prednisolone treatment for non-severe attacks in patients treated with asthma mAbs and will provide important information on whether corticosteroid treatment should be FeNO-directed.