Impact of Omalizumab on Rhinovirus Illnesses in Asthmatic Children

Study Background

Researchers investigated whether omalizumab treatment could decrease the frequency and severity of rhinovirus (RV) infections in children with asthma. Previous studies have indicated a link between allergic sensitization and an increased incidence of viral respiratory infections, particularly those caused by rhinoviruses. These infections often lead to exacerbations in asthma symptoms. Given that IgE antibodies play a crucial role in allergic responses, the study aimed to assess how omalizumab, which reduces IgE levels, affects asthma in this context.

Research Methodology

The study, published in the American Journal of Respiratory and Critical Care Medicine, was an interventional trial conducted in the United States. It focused on children aged 6 to 17 years with allergic asthma from low-income neighborhoods across eight cities. Participants were randomly assigned to receive either standard asthma care or omalizumab as an add-on treatment.

Conducted over a 90-day period during the fall of 2012 or 2013, researchers collected weekly respiratory symptom scores and nasal samples for rhinovirus testing. A rhinovirus infection was confirmed by detecting the virus, while the duration of infection was established by the number of consecutive positive samples. Exacerbations were defined as instances requiring systemic steroids, with viral exacerbations characterized by rhinovirus detection within a week before or after an asthma exacerbation.

Study Findings

In total, 478 participants were analyzed. Rhinovirus was identified in 57% of exacerbation samples compared to 36% of non-exacerbation samples, with RV-A and RV-C strains most strongly associated with exacerbations, while RV-B strains had a lesser impact.

Omalizumab’s Efficacy

The results indicated that omalizumab treatment significantly reduced the weekly detection rates of rhinovirus and the average duration of any rhinovirus infection. Additionally, the treatment group experienced shorter viral shedding durations and lower peak viral shedding levels. Although omalizumab effectively decreased the frequency of rhinovirus illnesses, it did not affect the duration of respiratory symptoms.

The findings support the hypothesis that interventions targeting IgE may hinder rhinovirus replication, thereby reducing both the frequency and severity of related respiratory infections. The study’s robust design, featuring a large sample size and regular monitoring, adds to its credibility, especially since participants were drawn from diverse geographic locations.

Limitations and Conclusion

While the study concentrated on rhinovirus detection, it did not account for other respiratory viruses that might also influence exacerbations and illnesses. Nevertheless, the findings provide compelling evidence that IgE-targeted treatments like omalizumab can diminish rhinovirus infections and related asthma exacerbations.

Author and Reference

Written by Maggie Leung, PharmD
Reference: Esquivel, A., Busse, W. W., Calatroni, A., Togias, A. G., Grindle, K. G., Bochkov, Y. A., . . . Gern, J. E. (2017). Effects of Omalizumab on Rhinovirus Infections, Illnesses, and Exacerbations of Asthma. American Journal of Respiratory and Critical Care Medicine, 196(8), 985-992. doi:10.1164/rccm.201701-0120oc