Tacrolimus with mycophenolate mofetil or sirolimus compared with calcineurin inhibitor-free immunosuppression (sirolimus/mycophenolate mofetil) after heart transplantation: 5-year results

Abstract

Background: Despite improvements in immunosuppressive therapy, the most advantageous combination for cardiac transplant recipients has not been established. This randomized controlled trial was performed to evaluate the efficacy and safety of 3 immunosuppressive protocols.

Methods: Between 2003 and 2005, 78 de novo cardiac transplant recipients were randomized 2:2:1 to receive steroids and tacrolimus plus mycophenolate mofetil (TAC/MMF; n = 34), TAC and sirolimus (TAC/SRL; n = 29), or SRL and MMF (SRL/MMF) plus anti-thymocyte globulin (ATG; n = 15). Steroids were withdrawn after 6 months.

Results: The 5-year survival was 85.3% for TAC/MMF, 93.1% for TAC/SRL, and 86.7% for SRL/MMF (p = 0.31 for TAC/MMF vs TAC/SIR; p = 0.47 for TAC/MMF vs SIR/MMF and p = 0.86 for TAC/SIR vs SIR/MMF). Despite the use of ATG, patients in the SRL/MMF group revealed numerically fewer freedom from acute rejection episodes: TAC/MMF, 82.4%; TAC/SRL, 85.2%; SRL/MMF, 73.3% (p = 0.33). Mean creatinine at 5 years revealed preservation of renal function in the SRL/MMF vs the TAC/MMF group (p = 0.045): TAC/MMF, 1.70±0.91 mg/dl; TAC/SRL, 1.44±0.65 mg/dl; and SRL/MMF, 1.25±0.46 mg/dl. Freedom from cardiac allograft vasculopathy was improved in the SRL/MMF group (93.3%) compared with TAC/MMF (73.5%) and TAC/SRL (80.8%) groups, reaching no statistical significance. Freedom from cytomegalovirus infection was TAC/MMF, 72.2%; TAC/SRL, 89.7%; and SRL/MMF, 86.7%. There was a trend toward improved freedom from cytomegalovirus infection with TAC/SRL vs TAC/MMF (p = 0.076). More frequent discontinuations of study medication occurred in SRL-based immunosuppression protocols (TAC/SRL vs TAC/MMF, p = 0.034; SRL/MMF vs TAC/MMF, p = 0.003).

Conclusions: The 3 strategies yield no survival advantage at 5 years, with higher numeric rates of rejection and adverse effects in the calcineurin inhibitor-free arm. A trend was observed in favor of freedom from cardiac allograft vasculopathy and preservation of renal function in the calcineurin inhibitor-free arm. However, the clinical relevance on outcomes is unclear because only few patients were receiving the assigned treatment protocols.