Tacrolimus in the treatment of idiopathic nephrotic syndrome.

The immunosuppressant tacrolimus (FK-506) is a calcineurin inhibitor with a widespread use for the prevention of graft rejection in transplantation medicine. Tacrolimus inhibits the activation of an essential transcription factor for the transcription of cytokine genes in T cells leading to a decreased production of cytokines such as IL-2 and IFN-gamma. As T-cell activation plays a crucial role in the pathogenesis of inflammatory glomerular diseases, there is an increasing number of reports on the use of tacrolimus in nephrotic syndrome. In idiopathic nephrotic syndrome, corticosteroid treatment constitutes the first-line therapy to achieve remission. In the case of steroid resistance or steroid dependence, alternative immunosuppressive strategies are needed. Cyclophosphamide and ciclosporin are well-established drugs in this condition. The present article reviews the pharmacodynamics, pharmacokinetics, safety and clinical efficacy of tacrolimus in steroid-resistant and steroid-dependent nephrotic syndrome.