Sublingual immunotherapy in the context of a clinical practice improvement program in the allergological setting: results of a long-term observational study.

The aim of this study was to assess the efficacy and safety of sublingual immunotherapy (SLIT) in a Clinical Practice Improvement (CPI) program carried out in allergology. The study was conducted between 1992 and 2001 using an observational type methodology in line with standard clinical practice. The program consisted of 4 basic steps: setting up of a decision-making tree; standardization of main diagnostic and therapeutic aspects; data collection; definition and evaluation of main clinical endpoints. Study patients were screened among 1508 patients with pollen and/or dust mite respiratory allergy, 350 of which, one year after having experienced a pharmacological treatment failure, were administered immunotherapy by injection (n = 111) or alternative route (n = 239). For each one of the three immunotherapy treatment groups (nasal, SLIT or injective) there was a control group of patients who, despite their poor response to pharmacological treatment, continued with pharmacological therapy alone (n = 314 in total; 68, 192 and 54 respectively). The observation of 130 SLIT patients, 106 of which were treated for at least 36 months, towards the control group evidenced that such therapy, apart from resulting efficient and particularly safe, has an unfailing protective effect against the development of asthma and new allergic sensitizations.