Is It Safe to Reduce Inhaled Corticosteroid Dose in Severe Asthma Patients Receiving Biologic Therapy?

Biologic therapies can control severe asthma and may modify its natural history beyond symptom control. However, step-down is not standardized, and its safety has not been clearly established.

This single-center retrospective cohort study reviewed adults with severe asthma on biologics (January 2019-May 2024). Step-down strategies (discontinuation of add-on therapy and/or inhaled corticosteroid [ICS] dose reduction) were described, success rates calculated, and clinical characteristics compared between groups with and without step-down.

Fifty-one patients were included, of whom 10 (19.6%) received omalizumab, 34 (66.7%) mepolizumab, and 7 (13.7%) benralizumab. After excluding 6 patients unsuitable for step-down assessment, 45 patients were compared. Step-down was attempted in 21 of these (46.7%) and succeeded in 17 (81.0%), defined as no systemic corticosteroid use, emergency visit, loss of control (ACT < 20), or exacerbation through the last visit. The most frequent interventions were ICS dose reduction (n = 7, 33.3%) and montelukast discontinuation (n = 7, 33.3%). Biologics had been received for a mean of 42.6 ± 14.0 months, and the reduced regimen was maintained for 8.15 ± 5.23 months. Compared with the non-step-down group, the step-down group had a higher proportion of males (p = 0.005) and longer follow-up (p = 0.007).

In this real-world cohort, step-down was feasible and appeared safe, with most patients maintaining the reduced regimen without deterioration in control or exacerbations. These findings support supervised treatment minimization in carefully selected, well-controlled patients, adding real-world evidence to a limited literature.