Dose Range Finding Study With rBet v1-FV - in Adult Patients With Birch Pollen-Allergic Seasonal Rhinoconjunctivitis

Inclusion Criteria: Patients must meet all of the following to be eligible for enrollment: * Is a male or female, aged 18 to 65 years, inclusive. * Has a clinical history of allergic rhinitis to birch pollen at least during each of the last 2 years. * Has a birch pollen specific IgE result (EAST) greater than 0.75 kU/L on blood sample drawn at Visit 1. * Has a positive skin prick test to birch allergen(s) at Visit 1, with a wheal diameter of at least 4 mm. * Has minimum qualifying symptom scores at Visit 2. * Patients with sensitization to cat epithelia, dog epithelia, Dermatophagoides farinae or Dermatophagoides pteronyssinus as per the skin prick test and/or EAST, may be included if sensitization is not clinically relevant. * Meets the concomitant medication restrictions described in the protocol. * Is normally active and otherwise judged to be in good health on the basis of medical history, physical examination and routine laboratory tests. * Is willing and able to give signed informed consent, and must have provided this consent. * Is willing and able to attend required study visits. Exclusion Criteria: A patient will not be included in this study if any of the following criteria apply: For female subjects: * Female subjects with childbearing potential (i.e., females are not chemically or surgically sterilised or females who are not post-menopausal) with a positive pregnancy test at Visit 1. * Female subjects with a negative pregnancy test at enrolment and not willing to use a reliable and highly effective method of birth control with a low failure rate (i.e. less than 1% per year) when used consistently and correctly during the trial, as judged by the investigator. * Pregnancy and lactation. * Female subjects seeking to become pregnant. General criteria: * Individuals weighing less than 40 Kg. * Not able to understand and comply with the requirements of the trial, as judged by the investigator. * Concurrent participation in any other clinical trial or participation in any other clinical trial during the previous 30 days. * Treatment with beta-blockers (locally and systemically). * Contraindication for adrenalin (e.g. acute or chronic symptomatic coronary heart disease, severe hypertension). Immunotherapy criteria: * Previous specific immunotherapy with birch or other early blossoming trees (e.g. Alder, Hazel) in any formulation within the past 5 years. * Any current immunotherapy. * Any previous specific immunotherapy with unknown or mixed allergens. Other allergies: \- Clinically relevant perennial allergies. Diseases and health status: * Clinically relevant rhinoconjunctival or respiratory symptoms related to other reasons. * Has diagnosed asthma. * Has PEF or FEV1 \< 80% of predicted normal * Any acute or chronic disease that, in the opinion of the investigator, would affect the study objectives or subject safety (e.g., Diabetes mellitus type I, malignant neoplasia, chronic renal failure, inflammatory diseases of liver or kidneys, emphysema, bronchiectasis). * Autoimmune diseases, immune-defects including immune-suppression, immune-complex-induced immunopathies (e.g. HIV, post-transplant patients, lupus erythematodes \[SLE\], Grave's disease, Hashimoto's thyroiditis) at time of screening. * Has a history of other clinically significant diseases which might impact efficacy analysis.