Long‐term use of romiplostim in the treatment of refractory immune‐mediated thrombocytopenia in a dog

A 6-year-old, male, neutered, crossbreed dog was diagnosed with primary immune-mediated thrombocytopenia. Initial treatment with prednisone and mycophenalate resulted in clinical and haematological improvement; however, multiple relapses occurred within the ensuing weeks. Two months after diagnosis, romiplostim was administered, leading to a rapid and sustained increase in thrombocyte count and complete clinical remission (DOGiBAT score 0). Prednisone and mycophenolate were successfully tapered and discontinued, while romiplostim was gradually reduced and stopped after 52 weeks, without evidence of relapse. No adverse effects were observed during treatment or follow-up. This case highlights the potential of romiplostim as a safe and effective adjunctive therapy for refractory primary immune-mediated thrombocytopenia in dogs