Efficacy and tolerability of house dust mites subcutaneous immunotherapy with monomeric allergoid: an Italian multicenter study

<b>Background.</b> Subcutaneous immunotherapy is an effective treatment of respiratory allergy and allergoids offer a treatment option characterized by reduced IgE-binding properties to improve the safety profile. Purpose of this study was to investigate the efficacy and the safety of an injective monomeric allergoid in patients with moderate to severe persistent allergic rhinitis due to house dust mites. <b>Methods.</b> in a perspective, controlled, observational study a suspension of 0.70 mL at 10 BU/mL containing a mixture of carbamylated extract of <i>Dermatophagoides</i> was injected monthly for 12 months, following a 5-weeks build-up phase (0.10-0.20-0.30-0.50-0.70 mL weekly), to 58 patients (mean age 25.1 ± 12.7). A matching group of 60 patients (mean age 34.0 ± 14.2) was observed as control, and both groups were allowed to assume standard pharmacotherapy. After one year, changes from baseline in visual analogue scale for symptoms and drugs intake were compared; satisfaction rate was based on patients' and physicians' judgements. <b>Results.</b> In respect to baseline both groups showed an improvement in symptoms with a significant difference in favor of immunotherapy. Drugs intake was significantly lower in patients receiving injections. High level of agreement was found between doctors and patients on their rate of satisfaction. No serious reactions occurred, and at least a mild episodic local or systemic reaction was reported by a limited number of patients. <b>Conclusions.</b> In routine practice injective monomeric allergoid of house dust mites was safe and associated with a perceived significant clinical benefit in persistent rhinitis shown by objective and subjective outcomes.