A nocturnal temperature controlled laminar flow device (TLA) maintains good control of severe allergic asthma (SAA) after withdrawal of Omalizumab therapy

Abstract

A nocturnal temperature-controlled laminar airflow (TLA) has been shown to reduce allergen load during sleep, and improve life quality of poorly controlled allergic asthma. To determine whether TLA could improve clinical outcomes of allergic severe asthma after withdrawal of omalizumab, 23 patients with severe allergic asthma (SAA) who had been stabilized for at least 6 months with omalizumab treatment discontinued their omalizumab and were randomized (1:1) to receive TLA (n=12) or not (non-TLA, n=11) for 48 weeks. Patients experiencing acute asthma exacerbation during the study period were back to omalizumab treatment. The time to asthma exacerbations, lung function, asthma control test score (ACT) and exhaled nitric oxide (eNO) were recorded. 82% of patients in non-TLA group had asthma exacerbation after omalizumab withdrawal. In contrast, only 17% of TLA group had asthma exacerbation (P=0.0001, Fisher’s test). The median time to first acute exacerbation in non-TLA group was 88 days [Hazard ratio (HR) 9.26, 95% CI 3.10~38.47, p=0.0005] that was significantly shorter than TLA group (median 200 days, HR 0.11, 95% CI 0.01~0.31). 83% of patients in TLA group had no exacerbation, stable FEV1, ACT score and eNO levels throughout the study. Patients of non-TLA group had an increase in eNO levels and decline in FEV1 and ACT scores after omalizumab withdrawal. In conclusion, inhalant exposure reduction with TLA maintained a stable control of SAA after omalizumab withdrawal. TLA may be an alternative treatment option for patients with inadequately controlled SAA requiring add-on anti-IgE therapy.