Allergic rhinitis (AR) is a common disease of nasal mucosa, affecting 10% to 40% of the population globally. Allergen specific immunotherapy (AIT) is the only etiological treatment available for AR.Traditionally, AIT is divided into subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT). Artemisia annua is one of the most important allergen that is responsible for seasonal AR in China during July and October.

The trial is a randomized, double-blind, placebo-controlled, multicentred, phase III trial. 702 subjects with allergic rhinitis caused by Artemisia pollen were recruited and randomized to the immunotherapy group and placebo group.

Inclusion Criteria:

• presence of seasonal rhinitis symptoms for over 2 years
• artemisia-specific immunoglobulin E (IgE) levels (ImmunoCAP) of class 3 or higher
• 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 severe asthma, perennial allergic rhinitis, cancer or other serious diseases that are unfit to receive allergen immunotherapy
• patients who are taking β-antagonists or have taken systemic corticosteroids in last 4 weeks
• patients whose Humulus- or Artemisiifolia-specific immunoglobulin E (IgE) levels (ImmunoCAP) same as or higher than Artemisia-specific immunoglobulin E (IgE) level.