Background: Daclizumab is a human monoclonal antibody that binds to the interleukin-2 receptor. It has been used as induction therapy in heart transplantation with repeated administrations over several weeks. At our institution, we use a two-dose regimen of daclizumab based on its extended half-life. We sought to determine the incidence of acute rejection with 2-dose daclizumab in cardiac transplantation.
Methods: Eighteen consecutive heart transplants performed at a single center were analyzed retrospectively. Patients received daclizumab (2 mg/kg) within 8 h of cardiac transplantation and a second dose (1 mg/kg) 2 wk thereafter. Maintenance immunosupression included mycophenolate mofetil, prednisone and either cyclosporine or tacrolimus, based on side-effect profile. The endpoint was the incidence of acute rejection as defined by a histologic grade >2 according to the classification of the International Society of Heart and Lung Transplantation.
Results: Four patients had acute rejections (all were 3A) during the first 3 months post-transplantation. All four patients had rejection at the first biopsy and only two had rejection thereafter. None of the rejections were hemodynamically significant and no patients were hospitalized. All except one rejection was seen in the context of low 2-h cyclosporine levels. The two-dose regimen was easier to administer on an outpatient basis and resulted in lower cost.
Conclusions: This preliminary report suggests that induction therapy with a two-dose regimen of daclizumab appears to be safe and well tolerated in patients undergoing cardiac transplantation.