Induction Immunosuppression with Anti-CD25 Monoclonal Antibody (Basiliximab) Allows Delayed Initiation and Uptitration of Calcineurin Inhibitor Post Cardiac Transplant

Background:The role of anti-CDmonoclonal antibodies in induction immunosuppression for cardiac transplantation remains unclear. This study sought to determine if basiliximab allows delayed commencement, slower uptitration and reduced nephrotoxicity or allograft rejection with cyclosporin. Methods: We performed retrospective analysis of cardiac transplant patients on cyclosporin, mycophenolate mofetil, and corticosteroids and compared the results depending on whether they received basiliximab post transplant. Data was collected for 21 days post transplant. Exclusion criteria: <18 yrs old, alternative immunosuppression, multi-organ transplant. Results: 39 patients studied (basiliximab: 22; nonbasiliximab: 17). More patients in the non-basiliximab group were ex-smokers (71% vs. 32%, p= 0.025) and type 2 diabetics (35% vs. 4.5%, p= 0.03) but had similar demographics for stroke, hypertension, mechanical support and indication for transplant. No patients received OKT3 or antithymocyte globulin. Time to cyclosporin initiation (mean± 1SD) was 0.12± 0.35 days for non-basiliximab versus 1.50± 2.54 days for basiliximab (p= 0.003). Therapeutic cyclosporin levels (250–300mg/L) were reached later in the basiliximab arm (11.1± 3.7 days) versus (17.1± 7.4 days) (p= 0.003). There was a trend to decreased Grade 3 rejection on day 14 in the basiliximab arm (p= 0.09). There were no significant differences in average creatinine clearance between the groups within the initial 21 days (p= 0.71). Conclusion: Post cardiac transplant, basiliximab allowed delayed initiation and time to therapeutic trough levels of cyclosporin with a trend to decreased severe rejection on day 14. Nephrotoxicity was not reduced. A larger study group is needed to evaluate basiliximab’s effect on rejection rate and renal function.