Sublingual Immunotherapy Using a House Dust Mite (HDM) Antigen Medical-Product for Canine Atopic Dermatitis: A Prospective Pilot Study

Abstract

An open prospective pilot clinical trial was conducted to evaluate the efficacy and safety of sublingual immunotherapy (SLIT). Fifteen patients with canine atopic dermatitis (CAD) who tested positive for either the Dermatophagoides pteronyssinus (Df) or Dermatophagoides pteronyssinus (Dp) antigens by serum antigen-specific IgE testing (Heska Aracept, Fujifilm VET Systems) were included. The SLIT was divided into an induction phase and a weekly maintenance phase of 6 months. Changes in clinical symptoms were compared using the Canine Atopic Dermal Inflammation Scale Index (CADESI-4), with pre-treatment as baseline and post-treatment as post-treatment. The antigen solution was a domestic drug (therapeutic mite allergen extract 100,000 JAU/ml, Torii Pharmaceuticals, Inc.) of house dust mite antigen mixed with Df and Dp. As a result, 2 dogs dropped out and 13 dogs completed the trial. Of the 13 cases that completed the trial, the baseline CADESI-4 was shown to a mean ± SD of 40.3 ± 25.9. Six months after SLIT, the CADESI-4 was decreased to 22.5 ± 22.0. Of the 13 patients, 8 (62 %) had a marked improvement in CADESI-4 (> 30 %) and 2 (15 %) had a worsening of CADESI-4. No serious adverse reactions such as anaphylaxis were observed during the trial. This suggests that SLIT with a domestic drug, house dust mite antigen solution, for CAD is safe in dogs and effective for 6 months based on the decrease in CADESI-4.