sirolimus + calcineurin inhibitor + prednisone

This is a combination immunosuppressive regimen consisting of sirolimus, a calcineurin inhibitor (such as cyclosporine or tacrolimus), and prednisone. It is primarily used to prevent organ transplant rejection, especially in renal transplantation, and has also been studied for the treatment of chronic graft-versus-host disease. Sirolimus acts as an mTOR inhibitor, suppressing T-cell and B-cell activation by inhibiting their response to interleukin-2. Calcineurin inhibitors (e.g., cyclosporine or tacrolimus) inhibit the phosphatase activity of calcineurin, thereby blocking T-cell activation via inhibition of IL-2 transcription. Prednisone is a synthetic glucocorticoid that broadly suppresses immune responses through multiple mechanisms including inhibition of cytokine production and lymphocyte proliferation[2][3][4][6]. This triple-drug regimen provides potent immunosuppression but increases the risk for adverse effects such as nephrotoxicity (especially with calcineurin inhibitors), metabolic disturbances, infections, and other complications[4][5].