Evaluation of the efficacy of a depigmented grass extract in the treatment of local allergic rhinitis

INTERVENTION: Product Name: Modified allergenic extract (depigmented and polymerized) of Phleum pratense Pharmaceutical Form: Suspension for injection INN or Proposed INN: Modified allergenic extract (depigmented and polymerized) of Phleum pratense Current Sponsor code: 6043 Concentration type: equal Concentration number: 1000 Pharmaceutical form of the placebo: Suspension for injection Route of administration of the placebo: Subcutaneous use CONDITION: Local allergic rhinitis; MedDRA version: 13 Level: LLT Classification code 10001726 Term: Pollen allergic rhinitis PRIMARY OUTCOME: Main Objective: To evaluate the efficacy of a grass extract administered subcutaneously, compared to placebo, in patients with local allergic rhinitis due exclusively to this allergen, based on the reduction of the symptom score and medication consumption. Primary endpoint(s): Efficacy variables; Rhinitis symptom score and medication consumption required to control those symptoms; ; Safety variables; ; Adverse events; ; ? Vital signs (blood pressure and heart rate). Secondary Objective: To evaluate if there are differences in quality of life parameters between the active and placebo groups; to evaluate if there are differences in the immune response between the active and placebo groups in in vivo parameters (skin tests, nasal wash, nasal provocation test); to evaluate if there are differences in the immune response between the active and placebo groups in in vitro parameters. IFN-γ, IL-13, IL-5, IL-8, IL-10, IL-12, IL-2, ECP, Tryptase, IgG, IgG4 and grass-specific IgE, Phl p1, 5, 7 and 12; tolerance of the cluster regimen used during the dose escalation and maintenance phases. INCLUSION CRITERIA: Patients with local allergic rhinitis due to grass sensitization, with Seasonal symptoms of at least one year's duration, according to the guideline: "Guideline on the clinical development of products for specific immunotherapy for the treatment of allergic diseases" CHMP/EWP/18504/2006 - Age: 18-55 years (male or female) - Negative grass pollen prick tests (LETI, S.A., wheal diameter < 3 mm) and negative specific grass pollen IgE, Phl p1, 5, 7, 12 (<0.35 kU/l) - Positive grass pollen provocation test (symptom score + acoustic rhinometry) and/or positive nasal grass pollen IgE (≥ 0.35 kU/l). - Obtaining informed consent before the subject's inclusion in the trial - Negative pregnancy test in women of childbearing potential and that they agree to use contraception for the duration of the study. Are the trial subjects under 18? No