Effectiveness and Response Predictors of Omalizumab in Treating Patients with Seasonal Allergic Rhinitis: A Real-World Study

BACKGROUND: Omalizumab has been proven effective and safety in treating seasonal allergic rhinitis (SAR) by several randomized clinical trials in many countries. However, there is lack of clinical reports of Chinese patients with SAR treated by omalizumab. OBJECTIVE: In the present real-world-designed study, we aimed to investigate the effectiveness of omalizumab in treating patients with SAR. METHODS: SAR patients administered omalizumab in various dosages were recruited, and follow-up was done. Their quality of life (QOL) and symptoms were assessed by the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ), Total Nasal Symptoms Score (TNSS), Asthma Control Test (ACT), and clinical outcomes were compared between post- and pre-treatment conditions. RESULTS: Sixty SAR patients received omalizumab therapy in the study (mean age 35.47±17.02 years, 35 females). Omalizumab treatment significantly improved the quality of life (change in RQLQ overall score: −2.08±1.01, paired t-test p<0.001) and nasal symptoms (change in TNSS: −7.33±2.50, paired t-test p<0.001) of SAR patients. In 21 patients with co-existing asthma, the ACT score significantly increased from 16.10 to 22.57 on average (paired t-test p<0.001), indicating better-controlled asthma. Using a threshold of ≥1 point improvement in RQLQ overall score, 83.3% of patients responded to omalizumab. The responder group had a higher baseline RQLQ score and TNSS (p<0.05), but both responders and non-responders had comparable scores after treatment. Multiple linear regression analysis identified the baseline RQLQ overall score as a predictor of change in the RQLQ score in omalizumab-treated SAR. CONCLUSION: Omalizumab is effective and safe in SAR treatment in a real-world setting.