Respiratory biologic drugs, vital for managing severe asthma, are being prescribed to a small fraction of eligible adults who also have obesity. These medications have demonstrated significant reductions in asthma exacerbations.
A retrospective analysis of electronic health records from 2018 to 2023 in a large U.S. health system examined adult patients with moderate-to-severe asthma and a Body Mass Index (BMI) of 25 kg/m² or higher, who met criteria for biologic therapy. Out of 5,805 eligible patients, only 11.9% received a prescription for respiratory biologics. This prescribing gap was even more pronounced in patients with obesity, where only 10.4% were treated. Higher BMI was linked to reduced odds of prescription and longer time to initiation.
Subspecialist care emerged as the strongest predictor for receiving biologics, suggesting that referral patterns and access to specialized, biomarker-driven evaluations are key to initiating advanced asthma therapies. This highlights a potential issue with how asthma severity and biologic eligibility are recognized and managed within routine care.
For patients with obesity who did receive T2-directed respiratory biologics, the analysis confirmed a significant decline in annualized exacerbation rates, underscoring the real-world effectiveness of these treatments even in higher BMI individuals. The study also investigated adjusted eosinophil criteria for biologic eligibility in obesity, but found no clear exacerbation benefit from the expanded eligibility. The findings point to a dual need: improving equitable access to current biologic therapies for patients meeting standard criteria, and refining how biomarkers are interpreted in obesity-associated asthma to ensure optimal treatment guidance.