The purpose of this study is to evaluate the safety and tolerability of multiple administrations of Birch-SPIRE. To make a preliminary assessment on pharmacodynamic parameters and clinical outcomes.

Inclusion Criteria:

• Male or female, aged 18 to 65 years;
• Minimum 1 year history of rhinitis with or without conjunctivitis on exposure to birch pollen
• Birch IgE ≥ 0.35 kU/L
• Positive skin prick test to whole birch allergen

Exclusion Criteria:

• Any past history of asthma
• FEV1 < 80% of predicted
• History of severe allergic reaction to birch allergen, severe drug allergy, severe angioedema or severe allergic reactions to food
• Acute phase skin response to whole birch allergen with a mean wheal diameter > 50mm
• Administration of adrenaline (epinephrine) is contraindicated
• History of severe drug allergy or anaphylactic reaction to food.
• History of any significant disease or disorder (e.g. immune system, pulmonary, cardiovascular, gastrointestinal, liver, renal, neurological, metabolic, malignant, psychiatric, major physical impairment, history of alcohol or drug abuse)