title: Sublingual immunotherapy with a standardized cat dander extract: evaluation of efficacy in a double blind placebo controlled study.
abstract: BACKGROUND
  Little information is available on the clinical efficacy of sublingual immunotherapy (SLIT) using extracts derived from mammalian epithelia.
  
  
  OBJECTIVE
  To assess clinical efficacy of cat SLIT based on natural exposure challenge test (NCT).
  
  
  METHODS
  Fifty cat allergic patients with rhinoconjunctivitis with or without asthma were included in a randomized double blind placebo controlled clinical trial of cat SLIT during 1 year. Twenty-five patients received active treatment and 25 placebo. Sublingual immunotherapy efficacy was assessed by natural exposure challenge to a cat in a cat-room and by skin tests. Airborne Fel d 1 levels, symptom scores and peak expiratory flow (PEF) values were monitored.
  
  
  RESULTS
  Thirty-three (66%) out of 50 patients completed the treatment. Fel d 1 content of the maximum concentration was 0.51 microg per ml. During the build up phase, the accumulated dose was 1.7 mug of Fel d 1 and during the entire length of the study was 17.1. No adverse reports were reported. The active group showed a marked reduction (62%) in symptoms during the NCT (P < 0.001) with no changes in placebo group. Active group also showed a reduced PEF response to cat exposure (P < 0.05), and an improvement in skin test reactivity to a standardized cat extract (P < 0.05), without significant changes in placebo group. Mean Fel d 1 exposure during the NCT was 6.2 +/- 2.21 ng/m(3).
  
  
  CONCLUSIONS
  The results suggest that the cat SLIT used in this study was able to improve cat allergy based on natural exposure challenge.
authors.affiliation: Servicio de Alergia, Hospital Ramón y Cajal, Madrid, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Alvarez-Cuesta
authors.forename: P
authors.initials: P
authors.lastname: Berges-Gimeno
authors.forename: E
authors.initials: E
authors.lastname: González-Mancebo
authors.forename: E G
authors.initials: EG
authors.lastname: Mancebo
authors.forename: E
authors.initials: E
authors.lastname: Fernández-Caldas
authors.forename: J
authors.initials: J
authors.lastname: Cuesta-Herranz
authors.forename: M
authors.initials: M
authors.lastname: Casanovas
mesh_terms: D000286:Administration, Sublingual; D000293:Adolescent; D000328:Adult; D000818:Animals; D001249:Asthma; D002415:Cats / Q000276:immunology*; D004311:Double-Blind Method; D005260:Female; D006197:Hair / Q000276:immunology*; D006801:Humans; D006967:Hypersensitivity / Q000628:therapy*; D007167:Immunotherapy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010919:Placebos; D012220:Rhinitis / Q000628:therapy*; D016896:Treatment Outcome
chemical_list: D010919:Placebos