Eculizumab in renal transplantation

Antibody-mediated rejection, be it acute, subacute or chronic, is currently recognized as the major cause of graft loss in kidney transplant recipients. Anti-HLA donor-specific antibodies are deleterious to the graft fate whether they pre-exist to the transplantation or appear in the course of transplantation. The role of complement is therefore prominent in most instances. As well, the role of complement activation is crucial in the recurrence of atypical hemolytic uremic syndrome post-transplantation (aHUS) as well as following ischemia-reperfusion injury leading to delayed graft function. Eculizumab, a fully humanized monoclonal antibody directed against the C5 component of the complement cascade is efficient in chronically and safely blocking complement activation for example in paroxysmal nocturnal hemoglobinuria. In the setting of kidney transplantation, there is convincing but still limited evidence that eculizumab is efficient in preventing both acute and chronic antibody-mediated rejection in highly sensitized recipients requiring desensitization before getting a living donor kidney transplant. Studies are currently ongoing to determine its efficacy and safety in ABO incompatible transplantation, in the prevention of acute and chronic rejection either with a living or a deceased donor kidney as well as in the prevention of delayed graft function. Similar to its efficacy in aHUS on native kidneys, eculizumab prevents or treats recurrence after kidney transplantation. There is still a lot of research to be performed in order to determine precisely the exact indications and the length of treatment with this very active but also very expensive drug that will undoubtedly revolutionize the current management of patients with donor specific antibodies (DSAs) and at risk of HUS recurrence.