Author(s): Javier Sola aff1 , Vanesa Sánchez aff1 , Araitz Landeta [*] aff2 , Begoña Madariaga aff2 , Alberto Martínez aff2 , Emilio Álvarez-Cuesta aff1
grass pollen; Phase I; safety; SCIT; tolerability
Allergic rhinitis is a global health problem that affect patients from all ethnic groups, socioeconomic conditions and age [1 ].
A cross-sectional study [2 ] showed that the prevalence of symptomatic sensitization, that is, clinical diagnosis of allergic rhinitis, was present in 30.9% of cases of the tested sample.
Among the allergens which cause this pathology, grass pollens make up more than a third of the cases. According to the study described in Alergológica 2005 [3 ], the number of patients with rhinoconjunctivitis sensitized to grasses is greater than 61.9% in the Madrid Community. Likewise, due to increased mobility in Europe, sensitization to inhaled allergens can differ in each European region [4,5 ].
Allergic illnesses in Europe affect 35% of the active population and thus treatment costs as well as the socio-economic impact are noteworthy. Allergic rhinoconjunctivitis, like the common cold, produces 30% cognitive dysfunction with a corresponding deterioration in learning and work productivity [ 6 ]. Recently, the GA2LEN estimated for the EU, avoidable indirect costs per patient insufficiently treated for allergy range between E55 and E151 billion per annum due to absenteeism and presenteeism, that is, E2405 per untreated patient per year [7 ]. Therefore, early treatment of this illness in order to avoid its progression is also very important from the economic point of view [ 6 ].
The most effective treatments for rhinoconjunctivitis and for extrinsic asthma are based on three pillars: avoidance of the allergen (when possible), treatment of the symptoms with medication and treatment of the causes using specific immunotherapy (SIT). In particular, the group of patients with moderate or severe allergy is the one which responds poorly to symptomatic treatment, and is where the choice of using SIT should be made [8 ]. Along these lines, Calderón's meta-analysis recommends the use of immunotherapy in patients with rhinitis whose symptoms are not under control in spite of receiving medical treatment [9 ]. In fact, SIT is currently the only available medical intervention that can alter the natural course of the disease [10 ]. SIT can improve allergic individuals' quality of life, reduce the long-term costs and burden of allergies, and change the course of the disease [10 ]. SIT not only effectively alleviates allergy symptoms, but it also has a long-term effect after the conclusion of the treatment and can prevent the progression of allergic diseases [10 ].
Before July 2009, clinical development of the treatment of allergic diseases was carried out in adherence to two primary guidelines [11,12 ]. Both documents focused exclusively on the development of medicinal products to treat allergic symptoms and did not include SIT. In consequence, clinical trials using SIT lacked a standardized approach, which made it difficult to compare vaccines and outcomes and also created uncertainty around the eventual approval for marketing. In 2009, the EMA issued new guidelines on the clinical development of...