Clinical Observation Of Omalizumab In The Treatment Of Moderate-Severe Allergic Asthma In Real-World Practice

BACKGROUND As an anti-immunoglobulin E(IgE)drug,omalizumab was approved as an add-on therapy for uncontrolled moderate-severe allergic asthma in China in 2017.Omalizumab has demonstrated efficacy and safety in clinical trials of patients with asthma,but patients in clinical trials do not veritably reflect the situation of the real-world populations.Real-world data with Chinese patients are limited.OBJECTIVE To observe efficacy and safety of omalizumab treatment in Chinese patients with moderate-severe allergic asthma in a real-world setting and explore whether the baseline characteristics such as serum total IgE and peripheral blood eosinophil level can be a predictor for the response of omalizumab.METHODS The present study was a retrospective single-center real-world study.Clinical characteristics of moderate-severe allergic asthma patients with omalizumab treatment were collected and clinical reservations about efficacy and safety after the initiation of omalizumab were recorded.The changes of asthma control test(ACT),oral steroid(OCS)dose,exacerbation rate before and after omalizumab treatment were compared in this study.The association between baseline characteristics such as serum total IgE and eosinophil level and the response of omalizumab was analyzed.RESULTS A total of 29 participants with moderate-to-severe asthma were involved in the Second People’s Hospital of Shenzhen in China from 2018.03 to 2020.12.Among them,there were 8 patients who had discontinued treatment within 16 weeks(Group A)and 21 patients who had continuously accepted the treatment of omalizumab over 16 weeks(Group B).In Group B,after omalizumab treatment for16 weeks,OCS doses(prednisone equivalents dose)decreased from 9.05 ± 11.47 to1.43 ± 3.59mg/d(P=0.006),ACT scores increased from 6.90 ± 2.53 to 21.19 ± 3.74(P<0.001)and exacerbation frequency decreased from 1.00 ± 0.77 to 0.43 ± 0.60 per three months(P=0.011)compared to baseline.9 of 21 patients(42.86%)in Group B accepted OCS prescription and their OCS dose decreased from 21.11 ± 6.51mg/d to3.33 ± 5.00mg/d(P<0.001)while 6 of them withdrew OCS.During the treatment,mild adverse reactions were observed in two patients: swelling,pruritus,and dizziness at the injection site after the second injection of omalizumab with one patient while mild rash,fatigue,and dizziness with another patient.Responders were defined as those who changed from ACT < 19 at the baseline to ACT ≥ 20 after 16 weeks of Omalizumab treatment or who achieved at least a 3-point improvement(minimally clinical important difference,(MID))in ACT score.66.7% of participants in Group B were responders which was higher than that of group A(12.50%)(P < 0.009).In group B,the rate of responders was higher in patients with baseline serum total IgE ≥180IU/m L compared with patients with baseline serum total IgE <180IU/m L(P <0.05).There was no significant relationship between eosinophil level and responders.CONCLUSIONS Omalizumab initiation in patients with moderate-severe allergic asthma resulted in improved exacerbation rates,reduced OCS doses,and improved ACT scores.Baseline serum total IgE ≥ 180IU/m L can predict the response to omalizumab in patients with moderate-to-severe asthma.