Smaller differences in the comparative effectiveness of biologics in reducing asthma-related hospitalizations compared to overall exacerbations.

BACKGROUND: Evidence on the comparative effectiveness of respiratory biologics remains sparse.

OBJECTIVE: We sought to evaluate the comparative effectiveness of omalizumab, mepolizumab, benralizumab, and dupilumab in a matched retrospective cohort of patients with asthma.

METHODS: We identified patients with asthma aged ≥18 years who were incident users of these biologics between November 1, 2018, and June 30, 2023, in administrative claims data from the FDA's Sentinel System and Merative™ MarketScan® Commercial Database. We compared asthma-related exacerbations and hospitalizations in the 12-months since biologic prescription in pairwise comparisons of propensity score-matched cohorts. Covariates used in matching included age, sex, allergic comorbidities, baseline asthma medications use, and the Charlson Comorbidity Index. Incidence rate ratios (IRR) and 95% CIs were estimated using negative binomial regression models.

RESULTS: Eight hundred and ninety-three mepolizumab users, 1300 benralizumab, 1170 omalizumab, and 1863 dupilumab patients were identified. The average age was 55 years and two-thirds of the participants were female. At baseline, over 80% of these individuals had an active prescription for an inhaled corticosteroid. Almost half of patients on dupilumab had concomitant nasal polyposis compared to 6-13% of patients on the other biologics. Covariates were balanced after matching. In matched analyses, dupilumab was associated with the lowest incidence of exacerbations over the follow-up period (vs dupilumab): mepolizumab (IRR: 1.36; 95% CI: 1.12-1.64), omalizumab (IRR: 1.33; 95% CI: 1.13-1.58), benralizumab (IRR: 1.19; 95% CI: 1.00-1.41). For exacerbations leading to hospitalizations, benralizumab and mepolizumab were associated with the lowest incidence of hospitalizations and the greatest difference was between mepolizumab vs dupilumab (IRR 0.76; 0.56 - 1.03).

CONCLUSION: Dupilumab was associated with the lowest incidence of overall exacerbations and mepolizumab with the lowest incidence of asthma hospitalizations in this administrative claims-based cohort of individuals with asthma. Despite matching propensity scores, residual confounding, such as baseline eosinophil count, may explain some of these findings.