Biannual dosing with the ultra‑long‑acting biologic depemokimab continues to provide sustained reductions in asthma exacerbations with a strong safety profile over two years. That’s according to the paper, “Long-Term Safety and Efficacy of Depemokimab in Patients With Type 2 Asthma: A Single-Arm, Open-Label Extension Study (AGILE),” recently presented at the American Academy of Allergy, Asthma & Immunology Annual Meeting. The results of the study were published in the Journal of Allergy and Clinical Immunology.
Depemokimab — approved by the U.S. Food and Drug Administration (FDA) in December 2025 as an add‑on maintenance therapy for patients aged 12 and older with severe eosinophilic asthma — binds to interleukin‑5 with high affinity and works for six months per injection, making it the first ultra‑long‑acting biologic available for respiratory disease.
“These findings will provide reassurance to practicing clinicians that this novel ultra-long-acting anti-IL5 agent has sustained efficacy and safety, and there should not be concerns regarding long-term use,” said Michael E. Wechsler, MD, in Healio. Dr. Wechsler is a professor of medicine at National Jewish Health and director of the National Jewish Health Cohen Family Asthma Institute in Denver.
The new findings come from the AGILE open‑label extension study, which followed patients who previously participated in the pivotal phase 3 SWIFT‑1 and SWIFT‑2 trials. Of the 762 original SWIFT participants, 641 entered the extension study and 629 were included in the final analysis.
According to the study’s researchers, 71% of patients experienced at least one adverse event — similar between those who continued depemokimab and those who switched from placebo (72% vs. 70%). Serious adverse events occurred in 9% of participants but none were treatment‑related or fatal, they noted.
The study’s authors reported that the most common events included:
- Nasopharyngitis: 10–14%
- Upper respiratory tract infections: 11–12%
- COVID‑19 infections: 7–8%
Rates of treatment‑related adverse events were low (2–4%), and fewer than 1% discontinued therapy due to side effects, the authors noted. Additionally, they reported that anti‑drug antibodies were detected in a small proportion of patients (7–10%), but they found no impact on safety or efficacy.
Researchers said that patients who continued depemokimab showed consistently low annualized exacerbation rates:
- Year 1: 0.51
- Year 2: 0.55
According to the results, those who switched from placebo after the SWIFT trials saw dramatic improvement in annualized exacerbation rates:
- Year 1 (placebo): 1.12
- Year 2 (on depemokimab): 0.58
The placebo‑to‑depemokimab group saw significant reductions — from 28 to 14 severe events year over year, the authors noted. Half of the patients who had an exacerbation during SWIFT had no exacerbations at all after switching, and 92% avoided any event requiring hospitalization or emergency care.
Researchers also emphasized that:
- More than 90% of patients completed the full two‑year regimen.
- Depemokimab maintained consistent efficacy even beyond one year.
- Additional long‑term, real‑world studies are warranted to continue evaluating safety and durability.
The study’s authors said they believed that depemokimab’s twice‑yearly dosing could represent a major shift in asthma treatment, particularly for patients who struggle with adherence to more frequent injections. Its strong two‑year safety and efficacy record positions it as a promising long‑term therapeutic option for individuals with severe type 2 eosinophilic asthma, they concluded.
