Study: Many Patients Switching Biologics Because of Perceived Lack of Efficacy Treating Asthma

Data from a study published in Annals of Allergy, Asthma & Immunology show that, when receiving treatment for asthma, many patients switched biologics because of a perceived lack of efficacy. The authors emphasized that these findings show the importance of individualized, patient-specific treatment planning when addressing severe asthma.¹

Asthma is a chronic lung disease that causes inflammation or swelling in your airways. These swollen airways can lead to difficulty breathing, chest tightness, coughing, and wheezing. Patients with moderate-to-severe asthma may have to take routine asthma controller medicines to decrease the amount of swelling in the airways and reduce symptoms.²

Biologics are a treatment option for asthma. Many of these biologics are antibodies, which are proteins that are designed to block specific molecules—tiny particles—within the human body. Biologics disrupt the specific cells or molecules that make the airways swell following exposure to certain triggers. According to the Asthma and Allergy Foundation of America, trigger exposure causes the molecules in your immune system to work together to create swelling in your airways. Biologics attach to these molecules and prevent them from causing inflammation and symptoms.²

In the treatment of asthma, biologic therapies have become a cornerstone; however, real-world data on the persistence and switching behavior remain limited. For this study, the investigators assessed switching patterns of biologic treatments and clinical rationale to better inform patient-centered care and guide long-term treatment strategies.¹

The retrospective, observational study utilized electronic medical record data from a large US-based network of specialty allergy and asthma clinics. Patients who had a diagnosis of severe asthma via ICD-10 codes (as a proxy for biologic use for asthma) and had at least 2 prescriptions or injections, or scribe verification, of a biologic after severe asthma diagnosis were included in the study. Initial biologic utilization and the first observed biologic switch—if a switch occurred—were described. Additionally, reasons for switching were manually abstracted from health care professional or specialist notes.¹

According to the findings, most patients remained on their initial biologic, with the highest persistence observed for tezepelumab (Tezspire; Amgen, AstraZeneca; 92%), dupilumab (Dupixent; Sanofi, Regeneron; 90%), and omalizumab (Xolair; Genentech, Novartis; 85%). Among patients who switched biologics, benralizumab (Fasenra; AstraZeneca) to dupilumab (44% of benralizumab switchers), or omalizumab to dupilumab (38% of omalizumab switchers) were the most common switching paths observed. Lack of efficacy was the most common reason for switching across all agents, cited in over half of switches (eg, 72% for benralizumab to tezepelumab, 75% for omalizumab to tezepelumab). Other reasons included adverse effects (AEs), payer challenges, or disease progression. Of those who switched from dupilumab, 28% reported switching because of AEs, whereas only 7% switched from omalizumab.¹

Pharmacists play a pivotal role in supporting patients with severe asthma, especially as biologic therapies become increasingly central to management. As medication experts, pharmacists help evaluate treatment effectiveness, monitor for AEs, and reinforce adherence, which are key responsibilities given that many patients in the study switched biologics due to a perceived lack of efficacy. By reviewing patients’ histories, patient-reported outcomes, and patterns of biologic persistence, pharmacists can identify when a therapy may no longer be meeting a patient’s needs and collaborate with prescribers and specialists to guide individualized treatment adjustments. Additionally, they also help patients understand how biologics work, manage expectations around symptom improvement, and navigate barriers such as insurance requirements or access challenges.

Through ongoing assessment, education, and coordination with the care team, pharmacists ensure that biologic treatment plans remain patient-specific and optimized for long-term asthma control.

REFERENCES

1. Chiarella S, McCann W, McEwen I, Novoa-Caicedo I, Pongdee T. Switching biologics in severe asthma: real-world insights and clinical rationale. Ann Allergy Asthma Immunol. 2025;135(5, Supplement 1):S5. doi:10.1016/j.anai.2025.08.024

2. Asthma and Allergy Foundation of America. Biologics for the Treatment of Asthma. Accessed December 11, 2025. https://aafa.org/asthma/asthma-treatment/biologics-asthma-treatment/