D2.121 - Seroprotection to influenza virus in vaccinated patients with bronchial asthma on biological treatment

With the increasing use of biological therapy for bronchial asthma, it is important to evaluate its impact on the effectiveness of annual seasonal influenza vaccination, which is indicated for all patients with bronchopulmonary pathology. The aim was to evaluate whether influenza vaccination provides sufficient seroprotection level (≥70%) in patients with severe and moderate asthma treated with biological agents (dupilumab, benralizumab, omalizumab, mepolizumab). 

Vaccination was performed after signing the voluntary informed consent in adult patients during the 2023-2024 flu season with an inactivated quadrivalent adjuvanted influenza vaccine with a reduced antigen amount from 15 to 5 μg of each strain on the day of the scheduled administration of monoclonal antibodies.

For the A/H1N1 strain, in the benralizumab (N=36), dupilumab (N=66), omalizumab (N=20), and mepolizumab (N=4) patient groups, the proportion of seroprotection increased from 27.8% (95% CI: 14.8–45.4%) to 86.1% (69.7–94.8%), p<0.005, from 19.7% (11.3–31.7%) to 93.9% (84.4–98.0%), p<0.005, from 25.0% (9.6–49.4%) to 95.0% (73.1–99.7%), p<0.005, from 25.0% (1.3–78.1%) to 75.0% (21.9–98.7%), p= 1.0, respectively. For the A/H3N2 strain, a significant increase was observed in all groups, but the largest increase was recorded in the mepolizumab group - from 0% to 100%. For the B/Austria strain, a statistically significant increase in the proportion of individuals with protective antibody titers was noted in all groups except mepolizumab. For the B/Phuket strain, the largest increase was noted in the dupilumab group, from 18.2% to 68.2%, p<0.005, the omalizumab group showed the smallest increase—from 35.0% to 70.0%, p=0.039.

The McNemar test results demonstrated a statistically significant increase in the proportion of individuals with protective antibody titers after vaccination in the overwhelming majority of cases.