Open trial of recombinant Der f 2 pullulan-conjugated immunotherapy in cats

Background: Allermmune HDM (Zenoaq) is a recombinant Dermatophagoides farinae 2 (Der f 2) pullulan-based immunotherapy vaccine whose efficacy on house dust mite allergic dogs has been demonstrated. There is no published information on its use in cats. Objectives: The objective of the study was to evaluate the safety and short-term effects of Allermmune HDM in Dermatophagoides farinae (Df)-sensitised cats. Materials and Methods: Eleven cats diagnosed with atopic skin syndrome received Allermmune weekly for six weeks then monthly for three months (total duration 18 weeks). On Weeks 0, 6 and 18 clinical lesions were assessed by the Feline Dermatitis Extent and Severity Index (FEDESI); owners assessed pruritus with a 10-cm Visual Analog Scale (pVAS). Concurrent medication use was recorded. The allergen-specific immunoglobulin (Ig)E were measured before study inclusion with a commercial serological assay. Results: There were no evident adverse effects. FEDESI and pVAS improved significantly after six weeks (p = 0.001 and p = 0.01, respectively). The pre-reatment Df-specific IgE levels were significantly higher in the cats with improved clinical scores than in the cats with no clinical score change (p = 0.009). Conclusions and Clinical Relevance: Allermmune HDM may be safe in cats and has the potential to alleviate signs of atopic skin syndrome. Allergen-specific IgE levels may represent an efficacy marker. Controlled studies of longer duration and larger sample size are worth pursuing.