Does omalizumab decrease respiratory viral infections in children with allergic asthma?

In children with allergic asthma, omalizumab (Xolair) decreases the frequency of symptomatic respiratory illnesses, but not their duration. It is expensive, however, and the authors don't report on its adverse effects or on how many asthma exacerbations or hospitalizations are prevented. (LOE = 1b)

Esquivel A, Busse WW, Calatroni A, et al. Effects of omalizumab on rhinovirus infections, illnesses, and exacerbations of asthma. Am J Respir Crit Care Med 2017;196(8):985-992.  [PMID:28608756]

Randomized controlled trial (double-blinded)

Government

Outpatient (specialty)

The Preventative Omalizumab or Step-up Therapy for Severe Fall Exacerbations (PROSE) study members randomized children from low-income cities to receive guideline-based asthma care plus placebo (n = 89) or add-on omalizumab (n = 348). The children were aged 6 to 17 years, had allergic asthma for at least one year, and had at least one exacerbation that required systemic corticosteroids or hospitalization within the preceding 19 months. The researchers administered omalizumab every 2 to 4 weeks according to the children's weight and IgE level. Every week for 90 days, the researchers collected nasal mucous samples to test for respiratory virus shedding. Additionally, the children and caregivers kept respiratory symptom diaries. The researchers enrolled the children in autumn to maximize the potential to be exposed to and develop respiratory infections. Slightly more than half of these little germ factories were already shedding viruses at the end of the first week! In addition to reporting that the omalizumab group had one fewer day of virus shedding than the control group and 0.4 fewer log units of peak shedding (who cares?), the researchers report that omalizumab decreased the frequency of illnesses (34% vs 58%; number needed to treat [NNT] = 5) and the frequency of viral illnesses AND overall illnesses (63% vs 71%; NNT = 13), but had no effect on the duration of symptomatic illness. The authors don't report on the adverse effects of omalizumab. And, by the way, according to GoodRx.com, omalizumab costs more than US$1000 a vial.