Use of mycophenolate mofetil to treat immune‐mediated skin disease in 14 dogs – a retrospective evaluation

BACKGROUND Mycophenolate mofetil (MMF) is a lymphocytotoxic immunosuppressive agent used in human and companion animal medicine for the treatment of immune-mediated disease. Mycophenolate mofetil is reported to have reduced myelotoxicity and hepatotoxicity when compared to azathioprine. OBJECTIVES It was hypothesized that treatment with MMF as a secondary agent with glucocorticoids would be effective in treating immune-mediated skin disease. In addition, adverse effects associated with the drug are reported. ANIMALS Fourteen dogs from a hospital population diagnosed with immune-mediated skin disease. METHODS A retrospective review of medical records from 2010 to 2015 was used to identify dogs with immune-mediated skin disease that were treated with MMF. RESULTS All dogs were treated with MMF (mean dose 14.7 mg/kg twice daily) in conjunction with glucocorticoids. Ten of 14 cases showed positive results, with complete remission in eight cases and partial remission in two cases. Mean time to remission was 5.7 weeks. Therapy was discontinued in one case (perianal fistula) due to lack of response. Adverse events were noted in six cases and included diarrhoea (n = 6), haematochezia (n = 2), vomiting (n = 3) and papilloma formation (n = 1). Therapy was discontinued in two cases with diarrhoea. Mycophenolate mofetil was discontinued in an additional case because of a diagnosis of neoplasia. All other adverse events were self-limiting or easily medically managed. No hepatotoxicity or bone marrow suppression was noted. CONCLUSION This study supports the use of MMF as a second-line immunotherapeutic in immune-mediated skin disease in dogs.