SYSTEMATIC REVIEW Omalizumab for the treatment of allergic rhinitis: a systematic review and meta-analysis* Abstract Background: Allergic rhinitis (AR), an IgE mediated inflammatory disease, significantly impacts quality of life of a considerable proportion of the general population. Omalizumab, a humanized monoclonal antibody against IgE, has been evaluated for both seasonal and perennial AR. We aimed to assess the efficacy and safety of omalizumab in randomized controlled trials (RCTs) in inadequately controlled AR. Methods: We conducted a systematic literature search of RCTs evaluating the safety and efficacy of omalizumab in AR. We syn- thesized evidence for clinical improvement of AR symptoms, quality of life, reduction of the use of rescue medication, and adverse events. Results: The systematic search returned 289 articles, of which 12 RCTs were eligible for data extraction and meta-analysis. Omali- zumab reduced the Daily Nasal Symptom Severity Score (DNSSS) by a summary standardized mean difference of -0.41 points with large heterogeneity; omalizumab significantly reduced the DNSSS both in the 3 cedar pollen-induced AR trials by -0.97 points and to a lower extent in the remaining five non-cedar trials by -0.19 points. Omalizumab also improved the Daily Ocular Symptom Severity Score (DOSSS) by a summary standardized mean difference of -0.30 points with large heterogeneity; the Rhino-conjunc- tivitis Quality of Life Questionnaire by a summary standardized mean difference of -0.45 points with no heterogeneity and the mean daily consumption of rescue antihistamines by a summary standardized mean difference of -0.21 with large heterogeneity. No statistically significant difference in the occurrence of adverse events was observed between omalizumab and placebo. Conclusion: Our findings further support the efficacy and safety of omalizumab in the management of patients with allergic rhinitis inadequately controlled with a conventional treatment. Key words: Anti-IgE, daily nasal symptom severity score; daily ocular symptom severity score, rhino-conjunctivitis quality of life questionnaire Sophia Tsabouri 1 , Georgios Ntritsos 1 , Fotios Koskeridis 1 , Evangelos Evangelou 1 , Petter Olsson 2 , Konstantinos Kostikas 1 1 University of Ioannina, Medical School, Ioannina, Greece 2 Novartis AB, Kista, Sweden Rhinology 59: 6, 501 - 510, 2021 https://doi.org/10.4193/Rhin21.159 *Received for publication: May 8, 2021 Accepted: August 17, 2021 501 Introduction Allergic rhinitis (AR) is a symptomatic nasal disorder induced by inflammation in the nasal mucosa after allergen exposure. It´s a common medical condition presenting with high prevalence in the general global population with a substantial impact on the quality of life affecting almost all daily activities of patients (1) . Symptoms of AR include paroxysmal sneezing, watery rhinor- rhea and nasal congestion and itching, frequently accompanied by ocular symptoms including itchy and watery eyes (2) . AR is a type I allergic disease mediated by allergen-specific IgE. Apart from specific allergen immunotherapy, currently available therapeutic approaches, including mainly antihistamines and corticosteroids, focus on symptom relief and although they do not provide a permanent solution, they still remain first-line treatment (3) . The concept of targeting IgE through the use of anti-IgE antibodies for the management of allergic conditions has been the focus of intense research in the last decades. Alt- hough some additional anti-IgE treatments have been evaluated