The frequency and predictability of switching biologic agents in severe asthma: A real-world perspective.

Background: While phenotyping assists in selecting the right biologic agent for severe asthma, the frequency of patients transitioning to a different biologic is also significant. Objective: We sought to identify the factors that predict switching between biological agents. Methods: The study involved 165 adults with severe asthma and included a 3-year follow-up period. Clinical and spirometric data were evaluated alongside the demographic characteristics of the patients. In addition to skin prick tests and specific immunoglobulin E (IgE) tests, eosinophil counts and total IgE measurements were assessed. Results: The patient group comprised 124 female participants (75%); the average age was 48 ± 13 years. Over half of the patients had eosinophilic asthma (56%) and allergic asthma (52%). In the first-line treatment, 111 patients (68%) were started on omalizumab, 43 patients (26%) on mepolizumab, and 11 patients (6%) on benralizumab. A total of 37 patients required a change in their biologic treatment. The 2 key factors influencing this switch were the initial annual number of asthma attacks and the level of improvement in the asthma control test score assessed during the first evaluation after starting the biologic (odds ratio 2.23 [95% confidence interval: 1.49-3.33]; Conclusion: Patients with higher annual attacks at baseline and lower responsiveness at the first postbiologic efficacy assessment can be useful in predicting switching status. However, further well-designed studies involving a larger number of patients and conducted over a longer term are needed to identify additional factors that could assist in selecting the most appropriate biologic.