Background: Tacrolimus-based immunosuppression seems safe and effective in liver and kidney transplantation. To assess the safety and efficacy of tacrolimus (TAC)-based immunosuppression after cardiac transplantation as well as the relative impact of tacrolimus on immunosuppression-related side effects such as hypertension and hyperlipidemia, we conducted a prospective, randomized, open-label, multicenter study of otherwise identical tacrolimus- and cyclosporine-based immunosuppressive regimens in adult patients undergoing cardiac transplantation.
Methods: Eighty-five adult patients (pts) at six United States cardiac transplant centers, undergoing their first cardiac transplant procedure, were prospectively randomized to receive either TAC-based (n = 39) or cyclosporine (CYA)-based (n = 46) immunosuppression. All pts received a triple-drug protocol with 15 pts (18%) receiving peri-operative OKT3 to delay TAC/CYA due to pre-transplant renal dysfunction. Endomyocardial biopsies were performed at Weeks 1, 2, 3, 4, 6, 8, 10, 12, 24, and 52. The study duration was 12 months.
Results: Patients were mostly male (87%) Caucasian (90%) with a mean age of 54 years and primary diagnoses of coronary artery disease (55%) and idiopathic dilated cardiomyopathy (41%). There were no significant demographic differences between groups. Patient and allograft survival were not different in the two groups. The probability and overall incidence of each grade of rejection, whether treated or not, and the types of treatment required did not differ between the groups. At baseline and through 12 months of follow-up, chemistry and hematology values were similar between the groups except serum cholesterol was higher in the CYA group at 3, 6, and 12 months (239 vs 205 mg/dL, 246 vs 191 mg/dL, 212 vs 186 mg/dL, respectively, p < 0.001). Likewise, LDL-cholesterol, HDL-cholesterol and triglycerides were significantly higher in the CYA group. More CYA patients received therapy for hypercholesterolemia (71% vs 41% at 12 months, p = 0.01). There were no significant differences in renal function, hyperglycemia, hypomagnesemia, or hyperkalemia during the first 12 months. More CYA patients developed new-onset hypertension requiring pharmacologic treatment (71% vs 48%, p = 0.05). The incidence of infection was the same for the two groups (2.6 episodes/pt/12 month follow-up).
Conclusion: Tacrolimus-based immunosuppression seems effective for rejection prophylaxis during the first year after cardiac transplantation and is associated with less hypertension and hyperlipidemia and no difference in renal function, hyperglycemia or infection incidence when compared to cyclosporine-based immunosuppression.