Allergic rhinitis (AR) is induced by an immunoglobulin E (IgE)-mediated reaction in the allergen-sensitized subjects, affecting 10% to 40% of the world population. AR could be divided into two kinds, perennial AR and seasonal AR (SAR).

In recent years, biologics have become promising drugs for allergic diseases. The efficacy and safety of Omalizumab in treating SAR have been well proven by previous studies. However, the efficacy in preseasonal treatment for SAR has not yet been studied before.

Inclusion Criteria:

• Male or female outpatients aged 18 to 60 years (inclusive).
• With history of SAR for at least two years, with/without conjunctivitis and without asthma
• Two or more nasal symptoms scores were ≥ 2 points during July - October in the last year.
• Sensitised to common autumn pollens including sagewort and ragweed (a specific IgE level ≥ 3.5 kU/L).
• Patients who have been informed of the nature and aims of the study and have given their written consent, willing to comply with the protocol.
• Patients who are able to understand the information given and the consent and complete the daily record card.

Exclusion Criteria:

• Patients with oral diseases/ allergies within the run-in period.
• Patients accepted any kind of operations within 4 weeks of the run-in period.
• Patients applied for systemic glucocorticoids within 4 weeks in the run-in period.
• Patients with PAR.
• Patients with any nasal condition that could confound the results of the study (chronic rhinitis, chronic rhinosinusitis with/without polyps).
• Whatever the co-sensitization leading to clinically relevant AR, conjunctivitis or asthma likely to significantly change the symptoms of the patient throughout the study.
• patients with comorbidity of severe asthma.
• Patients applying beta-antagonist (local or systemic appliance).
• Pregnant, breast-feeding / sexually active women of childbearing potential.
• Patients treated with AIT for pollens within 3 years.
• Participation in any clinical study within the 3 months of the run-in period.
• Patients at risk of non-compliance..
• Patients with immunologic suppression, diabetes mellitus, autonomic neuropathy, coronary heart disease or hypertension.