Why Asthma Often Comes Back After Stopping Biologic Drugs? Study Sheds Light

While biological drugs have significantly improved the quality of life for individuals with severe asthma, a new study from the Karolinska Institutet suggests they may not completely eliminate the underlying immune cells that drive inflammation. Published in the journal Allergy, the research raises questions about the long-term effectiveness of these treatments and highlights the need for continued therapy in many cases.

Biologics, including medications like mepolizumab and dupilumab, are widely prescribed for patients with severe asthma and are known to control symptoms effectively. However, little has been understood about how these drugs interact with the immune system at a cellular level.

In the study, researchers analyzed blood samples from 40 patients before and during biologic treatment. Using advanced techniques like flow cytometry and single-cell sequencing, they discovered that some immune cells associated with high inflammatory potential, rather than decreasing, actually increased during treatment. These cells are known to contribute significantly to airway inflammation in asthma.

"This suggests that biologics might not attack the root of the problem, no matter how much they help asthma patients during treatment," said Professor Jenny Mjösberg, senior author of the study. "Continued treatment might be necessary to keep the disease under control."

Given that biologics have only been in use for less than a decade, their long-term impact remains uncertain. The next phase of the study will examine samples from patients with extended treatment histories and include analysis of lung tissue to determine how immune cells behave directly within the airways.

Reference: Lorenz Wirth, Whitney Weigel, Christopher T. Stamper, Johan Kolmert, Sabrina de Souza Ferreira, Quirin Hammer, Maria Sparreman Mikus, Jakob Theorell, Lars Andersson, Ann‐Sofie Lantz, Eva Wallén‐Nielsen, Anne Petrén, Craig E. Wheelock, Apostolos Bossios, Nikolaos Lazarinis, Andrei Malinovschi, Christer Janson, Barbro Dahlén, Thomas Hochdörfer, Christopher Andrew Tibbitt, Sven‐Erik Dahlén, Valentyna Yasinska, Jenny Mjösberg. High‐Dimensional Analysis of Type 2 Lymphocyte Dynamics During Mepolizumab or Dupilumab Treatment in Severe Asthma. Allergy, 2025; DOI: 10.1111/all.16633