Depigoid birch pollen extract vaccine(Laboratorios LETI SL)

This study will assess efficacy and safety of intraseasonal specific short-term immunotherapy with Depiquick® Birch in patients with allergic rhinitis and or rhinoconjunctivitis with or without intermittent asthma that have a clinical relevant IgE-mediated allergic sensitization against birch pollen. The term "intraseasonal" means that patients will start with immunotherapy treatment during the birch pollen season, i.e. when the already experience allergic symptoms.