Biologics in renal transplantation.

The biologics used in transplantation clinical practice include several monoclonal and polyclonal antibodies aimed at specific cellular receptors. The effect of their mechanisms of action includes depleting or blocking specific cell subpopulations, complement system, or removing circulating preformed antibodies and blocking their production. They are used in induction, desensitization ABO-incompatible renal transplantation, rescue therapy of steroid-resistant acute rejection, treatment of posttransplant recurrence of primary disease such as nephrotic syndrome or atypical hemolytic-uremic syndrome, and in late humoral rejection. There are various indications for the use of biologic agents before and early or late after renal transplantation in both high- and low-risk recipients. In the latter situation, the biologics-based induction is used to further minimize immunosuppression maintenance. The targets of several biologic agents are present across a variety of cells, and manipulation of the immune system with biologics may be associated with significant risk of acute and late-onset adverse events; therefore, clinical risk-versus-benefit ratio must be carefully balanced in every case. Several trials on novel biologics are reported in adults but not in the pediatric population.