Immunotherapy is based on the principle of eliciting an immune reaction in order to block the negative effect of a specific disease-causing protein. The potential to treat diseases by means of immunotherapy instead of using conventional drugs represents an attractive opportunity in a number of chronic disease areas, including asthma and allergy. Resistentia's model to treat allergic diseases, and ultimately asthma, is to use the immune system to produce antibodies against the IgE molecules themselves. The resulting anti-IgE antibodies intercept and form complexes with the IgE molecules before they can bind to the mast cells and basophils and are thus able to block any allergen-triggered inflammatory reaction. The approach works in all types of IgE-mediated allergies independently of allergen, and also in patients sensitive to multiple allergens.