Impact of risk-stratified mycophenolate dosing in heart transplantation

Mycophenolate mofetil (MMF), the prodrug of mycophenolic acid, is a highly effective immunosuppressive agent in heart transplant therapy. While the FDA approved dose is 1500 mg twice daily, dosing is often reduced due to dose-dependent adverse effects. However, empiric MMF dose reductions may lead to sub-therapeutic dosing and impair clinical outcomes. Our single center protocolized a risk-stratified approach based on age and weight to dose 500 mg twice daily or 1000 mg twice daily to patients after heart transplantation. This retrospective single-center study analyzed 140 consecutive heart transplant patients who were initiated on our risk-stratified MMF protocol post-transplant. The analysis revealed that the composite rate of biopsy-proven rejection, graft loss, or mortality at 1-year post-transplantation was similar between the two groups. Incidence of neutropenia, thrombocytopenia, infection, cardiac allograft vasculopathy, or acute kidney injury by 1-year also showed similar results between the two groups. Risk-stratification of MMF dosing appears to be a safe and effective strategy after heart transplantation.