Systemic reaction rates with omalizumab, subcutaneous immunotherapy, and combination therapy in children with allergic asthma.

Abstract

Background: For children with moderate-to-severe persistent allergic asthma, omalizumab is effective. However, it is expensive, and there are no current guidelines for discontinuation. Subcutaneous immunotherapy (SCIT) is the only approach that can provide persistent beneficial effects after treatment is discontinued. However, SCIT is contraindicated in poorly controlled asthma. Therefore, we performed, to our knowledge, the first U.S. study that exclusively compared the safety of omalizumab, SCIT, and combination (omalizumab and SCIT) therapy in children with allergic asthma. Objective: We hypothesize that the systemic reaction (SR) rates in children who receive combination therapy are comparable with omalizumab alone. Methods: We performed a retrospective study of children ages 6-18 years old with allergic asthma who, from July 2010 to June 2017, received SCIT, omalizumab, or combination therapy in our children's allergy clinic. Our primary end point was to determine the SR rate among each of these groups. Results: We reviewed the records of 89 patients: 30 patients with SCIT (1550 injections), 30 patients with omalizumab (729 injections), and 29 patients with combination therapy (954 injections). In the SCIT group, 19 SRs (1.2% of injections) occurred in 10 patients (33%). In the omalizumab group, three SRs (0.4% of injections) occurred in three patients (10%). Similarly, in the combination group, three SRs (0.3% of injections) occurred in three patients (10%). Compared with the SR rate in the SCIT group, both omalizumab and combination groups had significantly lower SR rates (p = 0.045 and p = 0.011, respectively). The SR rates in children who received omalizumab and children who received combination therapy were not statistically different (p = 0.73). Conclusion: Children with moderate-severe persistent allergic asthma who received omalizumab or combination therapy had significantly lower SR rates compared with children with allergic asthma who received SCIT alone. SCIT in children treated with omalizumab was safe and may serve both as an omalizumab-sparing treatment and as a bridge to safely administer SCIT.