Real-World Effectiveness of Biologic Therapies for Severe Asthma in a Diverse Middle Eastern Cohort: Evaluation of Longitudinal Symptom Improvement.

Background and aim Biologic therapies have transformed the management of severe asthma; however, real-world comparative data from ethnically diverse Middle Eastern populations remain limited. We evaluated the longitudinal effectiveness of benralizumab, dupilumab, mepolizumab, and tezepelumab in routine clinical practice in Dubai. This study aimed to evaluate the real-world performance and effectiveness of biologic therapies for respiratory diseases within the unique, high-dust environment and ethnically diverse patient population of Dubai, thereby providing data to bridge the gap between controlled clinical trials and routine clinical care outcomes. Methods This is a retrospective, single-center study of 47 adults with moderate-to-severe asthma receiving biologic therapy, contributing 141 longitudinal observations at baseline, six months, and 12 months. Baseline demographic and biomarker differences were assessed using chi-square and Kruskal-Wallis analyses with Dunn-Bonferroni correction. Longitudinal symptom trajectories (shortness of breath {SOB}, cough, wheeze) were analyzed using generalized estimating equations (GEE) with a binomial distribution and a logit link, accounting for repeated measures. Multivariable logistic regression was used to evaluate predictors of SOB resolution at 12 months. Results Significant baseline differences in ethnicity, smoking status, weight, BMI, fractional exhaled nitric oxide (FeNO), and eosinophil counts reflected phenotype-driven biologic selection. Despite this heterogeneity, time on biologic therapy was the only independent predictor of symptom improvement. Each visit was associated with significant reductions in SOB (B = -3.93, p < 0.001), cough (B = -2.28, p < 0.001), and wheeze (B = -1.75, p < 0.001). Biologic class was not associated with differential symptom trajectories. The logistic regression model for SOB resolution demonstrated moderate explanatory power (pseudo R² = 0.397; likelihood ratio test {LRT} p = 0.054), with no biologic showing superiority. Adherence rates were high and adverse events were infrequent. Discussion In this real-world, multi-ethnic cohort, biologic therapy was associated with substantial and progressive symptom improvement over 12 months, independent of drug class. These findings support the comparable effectiveness of currently available biologics and reinforce the importance of prolonged treatment durations and longitudinal assessment in the management of severe asthma.