Randomized dose-response study of subcutaneous immunotherapy with a Dermatophagoides pteronyssinus extract in patients with respiratory allergy

Aim: To evaluate the efficacy of Dermatophagoides pteronyssinus (DPT) subcutaneous immunotherapyin allergic rhinoconjunctivitis patients. Patients & methods: This 17-week double- blind studyrandomized 136 patients (95 evaluable) to five dose groups of DPT depot extract (0.0625–0.75 skin prick test [SPT] units) or placebo, administered in a six updosing schedule. Results: A dose–response was observed for clinical efficacy (allergen concentration needed to induce a positive nasal provocation testresponse from baseline to final visit) and safety (adverse reactions). Local and systemic reactions occurred with 14.8 and 6.4% of administered doses, respectively; a single anaphylactic reactionoccurred in each of Groups 3, 4 and 5 (0.3% of doses). Conclusion: The risk–benefit profile appeared most favorable with a DPT dose of 0.125 SPT units.