Calcineurin inhibitor-free protocols: risks and benefits

Area of Science:

• Nephrology
• Immunosuppression Therapy
• Transplantation Medicine

Background:

• Calcineurin inhibitors (CNIs) are associated with nephrotoxicity and reduced long-term graft survival.
• Minimization protocols involving CNI withdrawal or avoidance are being investigated to mitigate adverse effects.
• CNI withdrawal strategies show promise for improving renal function and graft survival.

Discussion:

• Delayed and progressive CNI withdrawal appears safer than abrupt cessation.
• Maintaining high exposure to mycophenolate mofetil (MMF) or sirolimus (SIR) is crucial for minimizing acute rejection.
• CNI avoidance without induction therapy poses immunological risks; however, SIR + MMF with induction reduces acute rejection and chronic allograft nephropathy (CAN).

Key Insights:

• SIR-based treatments showed lower incidence of CAN, cancer risk, and improved blood pressure and uric acid profiles compared to CNI-based treatments.
• SIR-based protocols were associated with more frequent hyperlipidemia, delayed wound healing, lymphocele, arthralgias, and thrombocytopenia.
• Graft biopsies remain the most reliable monitoring method; preliminary drug lymphocyte binding assays may aid immunosuppression tailoring.

Outlook:

• Longer-term follow-up is necessary to confirm the benefits of CNI avoidance strategies on patient and graft survival.
• Further research is needed to determine the applicability of SIR or SIR + MMF protocols to high-risk patient populations.
• Non-nephrotoxic immunosuppression combinations like SIR and MMF may significantly alter the course of CAN and impact long-term patient survival.