Safety and Efficacy of Specific Immunotherapy With an Aluminium Hydroxide-adsorbed Allergoid Preparation of Birch Pollen Allergens
Condition: Pollen Allergy
MeSH terms: Rhinitis, Allergic, Seasonal
Study type: Interventional
Phase: Phase 3

Summary: 
      The aim of this clinical trial is to show safety and efficacy of the allergoid preparation of
      birch pollen allergens in the treatment of birch allergic patients in a representative number
      of patients.
    

Detailed description: 
      Type I allergy is an immune-disorder which stems from the formation of IgE antibodies against
      proteins and glycoproteins from plants, insects, animals and fungi, most of which for healthy
      subjects are considered to be harmless. However, in allergic patients the cross-linking of
      specific IgE-antibodies on effector cells by allergens activates an immunological cascade
      leading to the symptoms of Type I allergy including rhinitis, conjunctivitis, asthma, and
      anaphylactic shock. Pollens from wind-pollinated plants including trees, grasses and weeds,
      are amongst the most frequent and potent elicitors of Type I allergy. It is not possible to
      avoid exposure to these pollens and therefore the symptoms that patients inevitably suffer
      must be treated with either symptomatic medication or allergen specific immunotherapy.

      The Betulaceae family includes the genera Alnus (alder), Betula (birch) and Corylus (hazel).
      Trees belonging to these genera are widespread in middle and northern Europe and, in
      combination with the fact that they shed large quantities of wind-borne pollen, leads to
      their allergenic significance. The prevalence of sensitisation to birch pollen has been
      studied, and in the case of a middle European (Viennese) population, for example, it has been
      demonstrated that approximately 40 % of patients with allergic rhinitis are sensitised.
      Although the pollen season for any one genera seldom lasts for more than a few weeks, the
      well-documented cross-reactivity between the different Betulaceae and other tree pollens of
      the Fagales order contributes to a protracted season of symptoms for many allergic patients.

      Allergoids are prepared by chemical modification of partially purified native aqueous
      aller-gen extracts. Native allergen extracts are depleted of components with a molecular mass
      of less than 5000 Dalton by diafiltration prior to chemical modification with aldehydes. The
      modification causes a substantial reduction in the allergenicity of the extract as can be
      judged by skin prick testing, provocation testing, histamine release from sensitised
      leukocytes and measurement of IgE-binding activity by RAST-inhibition. However, immunogenic
      activity and T-cell reactivity are retained. These properties enable allergoids to be used as
      a basis for allergen specific immunotherapy with a reduced risk of inducing IgE-mediated
      side-reactions and the possibility of administering larger doses of immunogen over a shorter
      time course than with native allergens.
    

Intervention name(s): Birch pollen allergoid; Placebo
Intervention type(s): Biological; Other
Intervention description(s): Subcutaneous injections were applied in the upper arm. Vials with three different concentrations were used: Strength A (1000 TU/mL), strength B (10 000 TU/mL) and strength 0 (100 TU/mL) by dilution of strength A.; Sterile aluminium hydroxide suspension for subcutaneous injection were applied in the upper arm. Vials with strength A contained 0.0125 mg/mL and with strength B 0.125 mg/mL histamine-dihydrochloride and strength 0 was produced by dilution of strength A. The vials containing the placebo solution were identical in their outer appearance with the active study preparation of the birch pollen allergoids.
Other intervention name(s): specific immunotherapy; Comparator
Intervention MeSH terms: Immunomodulating Agents
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: specific immunotherapy; birch pollen allergy; Allergovit