FC‐55 Efficacy of low‐dose immunotherapy in the treatment of canine atopic dermatitis: a prospective, double‐blinded study

Abstract

There are anecdotal reports of increased effectiveness of allergen‐specific immunotherapy (ASIT) with doses of vaccine lower than that recommended by the manufacturers. However, no controlled studies have been carried out. The aim of this prospective, double‐blinded study was to evaluate whether induction and maintenance with low‐dose (LD) ASIT resulted in a different success rate compared with the standard dose (SD). Twenty‐seven dogs with confirmed atopic dermatitis were allotted by block randomisation to two groups. One (n = 13) received SD ASIT; the other (n = 14) received LD ASIT (1/10 of the SD) following the same frequency protocol. Cases were graded at 0, 3, 6 and 9 months for clinical signs using a modified Canine Atopic Dermatitis Extent and Severity Index (mCADESI) and for pruritus using a 0–5 descriptor scale. There were no significant differences between the groups in the pruritus and mCADESI scores (P > 0.155) at the end of the study. Changes in pruritus (P > 0.920) and mCADESI (P > 0.296) scores from the beginning to the end of the study were similar in both groups, with pruritus scores in both groups not changing during the study (P > 0.052). However, significant reductions in mCADESI scores were seen in both groups (P < 0.032). Six dogs achieved a final pruritus score of 0, six dogs achieved a reduction in pruritus score, and 15 did not improve or worsened. There was, therefore, no evidence that LD ASIT was more effective than the standard protocol. Funding: Petsavers, British Small Animal Veterinary Association, Wellcome Trust.