We hypothesized that the use of CL, alone or in combination with ULDA, would improve survival to discharge and at 90 days without important adverse effects compared with ULDA alone in client-owned dogs with pIMHA treated with standard immunosuppressive therapy. The purpose of this study was to compare the survival to discharge and the 90-day survival rate between dogs with pIMHA treated with CL, alone or in combination with ULDA, compared with dogs treated with ULDA alone in conjunction to standard immunosuppressive therapy. In addition, the frequency of fatal and nonfatal thrombotic episodes, transfusion requirements, and the clinical evidence of hemorrhage among the 3 treatment groups were compared.